Computer Audio Asylum

Music servers and other computer based digital audio technologies.

Return to Computer Audio Asylum

Message Sort: Post Order or Asylum Reverse Threaded

Page: [ 1 ] [ 2 ]

Improved Regen sound

79.97.72.230
Posted on November 22, 2015 at 13:43:48
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001



I was asked for details of an easy & reversible modification to the Regen that greatly improves its sound quality.

This is not another PS to plug into the DC input of the Regen - it's a bypass of the 3.3V on-board regulator with a 3.3V LiFePo4 battery supply. I know the regulators are said to be state of the art but a LiFePO4 battery smashes this out of the park.

Obviously you need to open up the Regen to connect a battery to the output from the 3.3V regulator & ground, thus bypassing the regulator. There is a ceramic capacitor C3 right at the output of that regulator - the reg at the top of the pic - REG33.

There's a copper via with a 5 beside it at top of that C3 capacitor - this is the GROUND point for connection of the negative battery pole. The other side of the capacitor is the connection to 3.3V positive (the one with two vias side-by-side). You need to attach the battery + pole to this point - soldering to one of these vias is best. It's very easy to reverse this if desired.

This powers the USB hub chip & the clock which is all that's needed for audio devices that don't need USB Vbus 5V power for signalling or for powering the audio device. If your need 5V supply you can still do this tweak but you need to supply the 5V separately

BTW, I forgot to include this: this provides a far superior sound than using 2 of the same batteries to power the Regen through its DC input so it's not just the batteries that make the difference but bypassing the REG33 also.

This signifies, to me, that the regulator is a limiting factor. The likely reason for this improvement might be that the clock is getting a cleaner PS particularly at low frequencies where Fmak reported issues with these regs? It is a disputed but widely held belief that reduced close in phase noise is one of the most critical factors for sound quality - LF noise on the clocks PS is one source of this close-in phase noise, the other being inside the oscillator itself (the crystal cut & it's surrounding circuitry).

I don't exactly know how a better PS on the Regen's clock & USB hub chip translates into a better sound downstream at the audio device - I don't believe any measurements have yet revealed this?

Try it & post your reports

Edit: I am reminded by some of the posts on this thread to warn people that they do this at their own risk & that they should be somewhat competent in DIY to do this. These batteries can put out a lot of power - treat them with respect - as you would a car battery - they are that powerful

 

Hide full thread outline!
    ...
I was thinking about opening that thing today, and then ..., posted on November 22, 2015 at 13:59:12
rickmcinnis@dogwoodfabrics.com
Audiophile

Posts: 3040
Location: Atlanta
Joined: December 15, 2003
 I see this. I have been wondering how difficult this is to do since reading about it within the "report" at Tir Na.

A few questions.

Are you leaving the PCB out of the enclosure? I am assuming you are.

Does the internal regulator act as a float charger or are you charging the battery when not using the REGEN? Or can the internal regulator be used to charge the battery?

THANKS,



 

Should have looked below , posted on November 22, 2015 at 14:05:20
rickmcinnis@dogwoodfabrics.com
Audiophile

Posts: 3040
Location: Atlanta
Joined: December 15, 2003
 and would see the charging aspect was addressed.

Glad you are participating here but hope it does not diminish your posts at Tir Na!

Take care,

 

RE: Improved Regen sound, posted on November 22, 2015 at 14:13:52
theob
Audiophile

Posts: 3180
Location: ann arbor michigan
Joined: November 4, 2000
 Assume you are talking about C3? Also can the solder points be made on the bottom rather than the top? Bottom looks like a clean access point.

 

RE: Should have looked below , posted on November 22, 2015 at 14:25:47
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 Good questions, Rick
You can try using the 3.3V regulator as a trickle charger for the battery but remember powering the Regen from the DC input will also power the 5V regulator which may put some noise on the ground plane.

Try it & post your comments here.

 

RE: Improved Regen sound, posted on November 22, 2015 at 14:31:40
kenzo
Audiophile

Posts: 955
Location: San Francisco
Joined: September 27, 2003
 Wouldn't it be easier to simply connect a battery using a dc connector to go right into the existing DC power input socket on the case?

Voila' no opening the case, no soldering/de-soldering, no voiding of warranty, instant test? etc.

 

RE: Improved Regen sound, posted on November 22, 2015 at 14:37:41
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 Sorry I didn't say this in my first post - I'll correct that now! This method, using a LiFePo4 battery to provide 3.3V power, bypassing the 3.3V onboard regulator, provides a far superior sound than using 2 of the same batteries (for 6.6V) to power the Regen through its DC input. This signifies that the regulator is a limiting factor.

 

RE: Improved Regen sound, posted on November 22, 2015 at 14:43:27
kenzo
Audiophile

Posts: 955
Location: San Francisco
Joined: September 27, 2003
 well I haven't tried the mod but this is definitely one of those cases where I would be somewhat skeptical that there could be audible difference, sorry.

 

RE: Improved Regen sound, posted on November 22, 2015 at 14:48:59
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 Sure, nothing wrong with being skeptical - that's why I said for people to try it & post their comments.

I believe rickmcinnis might have a Regen & LifePO4 batteries so he might be first to post if he's willing to try it?

 

RE: Improved Regen sound, posted on November 22, 2015 at 21:22:23
fmak
Audiophile

Posts: 13158
Location: Kent
Joined: June 1, 2002
 If you don't even want to try it because yu dn't believe it, why bother arguing?

 

Battery Specifics, posted on November 22, 2015 at 21:34:33
fmak
Audiophile

Posts: 13158
Location: Kent
Joined: June 1, 2002
 There seems to be a wide range of LiFePO4s on sale with A123s being much more expensive.

Can you please post details of the one you find best, it's capacity, and the charging arrangement?

Doesn't the hard connection of an active charger propagate noise and what about the battery's self noise?

I agree with you about the regulator, which I assessed when it came out. This one is susceptible to noise pickup, especially LF, which is bad for the clock. I posted this in CA but the post got 'buried'.

Thanks for the suggestions.

Right now, I believe that the power supply into the Regen stock unit also makes a big difference. I have tried 3 - 7.4V LiPO, 2 9Vs into another 7.8V Demo TPS regulator, and they all sounded different, with the better SQ from the battery and a SMSL P1 regulator. A Teradak 9V is not good at all.

 

RE: Improved Regen sound, posted on November 22, 2015 at 22:20:43
kenzo
Audiophile

Posts: 955
Location: San Francisco
Joined: September 27, 2003
 LOL, arguing? Are you a J.D.?
Are you sure you even know what an argument is? LOL

 

RE: Improved Regen sound, posted on November 22, 2015 at 22:33:02
kenzo
Audiophile

Posts: 955
Location: San Francisco
Joined: September 27, 2003
 Check out for a proper argument

https://www.youtube.com/watch?v=wdoGVgj1MtY

 

RE: Battery Specifics, posted on November 22, 2015 at 22:40:05
John Elison
Audiophile

Posts: 23900
Location: Central Kentucky
Joined: December 20, 2000
Contributor
  Since: January 29, 2004
 You can get 123A Lithium Batteries through SureFire at a fair price.

 

RE: Improved Regen sound, posted on November 22, 2015 at 23:34:07
pictureguy
Audiophile

Posts: 22597
Location: SoCal
Joined: October 19, 2008
 i'd just like to make a few 'notes' on batteries and Lithium chemistry in more particular.

It is important to note 2 things. Lithium and Lithium ION batteries are 2 different categories.
But in EITHER you will have a choice of several chemistries. This leads to one major, common outcome. You will have a wide choice of Cell Voltage to deal with. The Lithium Polymer with very high energy density typically has a cell voltage of 3.7 volts. So, a '3 cell' battery will be 11.1 volts fully charged. These batteries are also rated with a 'C' value which somehow reflects the ability to discharge very rapidly. Some of the hobby motors used can Easily have in excess of a 40 amp draw. A low internal resistance battery is ESSENTIAL.
Some other lithium chemistries are both higher and lower voltage. Some are low enough to be used as direct replacements for your good old Alkaline battery.

A little research on the part of those wishing a battery replacement should yield some good results. I'm certain that a low internal resistance battery which is also low noise CAN be found.
One in particular, a Li-SOCl2 chemistry is good in VERY cold conditions. This battery, if kept cold MAY also have lower noise? Call it about 3.5 volts in use. I have NO idea how to 'refrigerate' a battery in-use.

Some lithium cells are and some are NOT rechargeable. Don't try to recharge a single-use cell or you might have a problem.

The Hobby Shop types sell a recharger BAG to contain any potential problems when recharging your Li-ion battery and some of the chargers are VERY smart, indeed, even capable of 'balancing' the voltage between cells.

In some of the above posts, I see reference to both a 5v and 3v regulated PS. This, I think, means you need a battery to supply a higher voltage then than highest output voltage you wish.
Too much is never enough

 

RE: Improved Regen sound, posted on November 23, 2015 at 01:49:21
fmak
Audiophile

Posts: 13158
Location: Kent
Joined: June 1, 2002
 This is not a forum for destructive I don't believe posts, or shouldn't be.

 

RE: Battery Specifics, posted on November 23, 2015 at 02:35:34
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 No, no - be very careful - they seem to be Lithium ion batteries & not Lithium Ferrous nano Phopsphate (LIFePO4). The major difference being that the Lithium batteries operate at 3.7V whereas LiFePO4 operate at a constant 3.3v which is what you want.

You don't need the A123 make of LiFEPO4 batteries, any LiFEPO4 will do - the size is 26650 - try searching for these. You want the ones with tabs already welded onto the battery ends as it makes it much easier to solder wires to. Something like these

 

RE: Improved Regen sound, posted on November 23, 2015 at 02:48:00
theob
Audiophile

Posts: 3180
Location: ann arbor michigan
Joined: November 4, 2000
 First of all thank you very much for your post. Since, per my other post, I still wasn't sure of where to tap into I measured the spot I believe/ I think you described. When I measured via 5 to the bottom of C3 I got -3.3 volts. Do I still have the wrong points to bring in a LiFePo4 battery?

 

RE: Improved Regen sound, posted on November 23, 2015 at 03:59:37
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 Are sure you don't have the leads reversed?

 

RE: Improved Regen sound, posted on November 23, 2015 at 04:17:30
theob
Audiophile

Posts: 3180
Location: ann arbor michigan
Joined: November 4, 2000
 Pretty sure. Probably does not make a difference to run as a free standing power source but makes a big difference if one is to use the power plug as a trickle charge .

 

RE: Improved Regen sound, posted on November 23, 2015 at 04:22:32
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 I'm not in my office at the moment & haven't got the board in front of me but I was pretty sure that the via with the number 5 beside it (just above the ceramic cap) was the positive pole.

Don't reverse connect the battery - it will burn out the ICs - it's not a floating PS!

 

RE: Improved Regen sound, posted on November 23, 2015 at 04:29:11
theob
Audiophile

Posts: 3180
Location: ann arbor michigan
Joined: November 4, 2000
 This is really a conundrum. I want to do the mod (I have batteries) but right now I am not clear on what to do.

 

RE: Improved Regen sound, posted on November 23, 2015 at 04:32:16
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 Wait until I'm back in my office in about an hour & I will measure the voltage points again to confirm

 

RE: Improved Regen sound, posted on November 23, 2015 at 04:38:28
theob
Audiophile

Posts: 3180
Location: ann arbor michigan
Joined: November 4, 2000
 Ok thanks

 

RE: Improved Regen sound, posted on November 23, 2015 at 05:46:39
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 OK, I'm very, very sorry - you are correct - the via near "5" is the GROUND & the other end of the cap is 3.3V.

I'm glad you measured this before connecting anything - good DIY practise always pays

Where I went wrong is that I used a twisted pair of wires from a CAT5 cable to make this connection & mixed up the colour Vs polarity!!

I'll change this on my first post

 

RE: Improved Regen sound, posted on November 23, 2015 at 05:54:04
theob
Audiophile

Posts: 3180
Location: ann arbor michigan
Joined: November 4, 2000
 Thanks

 

RE: Improved Regen sound, posted on November 23, 2015 at 06:03:17
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 Interested to hear your impressions!

 

RE: Improved Regen sound, posted on November 23, 2015 at 06:33:56
theob
Audiophile

Posts: 3180
Location: ann arbor michigan
Joined: November 4, 2000
 In my system I have 2 Regens back to back. Since the 1st Regen into the 2nd Regen does not require the 5 Volts I put the
JK mod into the that Regen. My dac does require the 5 V. Since as I recall Swenson saying this element of the Regen does not pull a lot of current I have a pair of A123 driving very narrow wires just pushed into the via holes to test proof of concept. So since its not soldered yet its not optimum but it sounds better already. More focused less loose than baseline. I will solder and restate my comments

 

RE: Battery Specifics, posted on November 23, 2015 at 06:34:06
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 You don't need A123 batteries, I just mentioned them as being the first to market & probably the best but for this use any LiFePO4 battery will do, I believe.

To charge it just provide a 3.3 or 3.4V supply to the battery on a continuous basis - this will just trickle charge it. The only problem you could possibly have is if you let the battery deplete by running power from it & not charging it. This is not recommended for the battery health & recharging from depleted draws a large an amount of current from the charger- you just need to either avoid this situation or recondition the battery with a charger that can handle a large current draw.

I already answered the question about any noise coming from the charger - the battery acts a a very large capacitor effective over a wide frequency range & absorbs 99% of any noise. Try it with various chargers & see if you can hear or measure noise on the battery output.

As regards self-noise - this is based on an old report on batteries in TNT. This report didn't include these modern battery chemistries. There are some NIST reports on the noise of these batteries showing exceptionally low noise

 

RE: Improved Regen sound, posted on November 23, 2015 at 06:38:59
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 Very good!
I would suggest using only 1 Regen with this mod & providing the 5V needed in an alternative way.

I believe you are missing some of the benefit of the "direct" 3.3V battery supply by passing through a second Regen

 

RE: Improved Regen sound, posted on November 23, 2015 at 06:51:06
theob
Audiophile

Posts: 3180
Location: ann arbor michigan
Joined: November 4, 2000
 Yes but how do I supply the 5 volts to the dac? Would appreciate your ideas.

 

Ready to go after I order a battery, posted on November 23, 2015 at 07:07:00
rickmcinnis@dogwoodfabrics.com
Audiophile

Posts: 3040
Location: Atlanta
Joined: December 15, 2003
 Having the board outside of the case makes for an easier installation with WAVE IO.

Don't have a spare 26650 so will order one today. Plus, as you know, my DAC project is still underway so I will be making the mod but will not be able to report for a week or so.

 

RE: Improved Regen sound, posted on November 23, 2015 at 07:18:29
theob
Audiophile

Posts: 3180
Location: ann arbor michigan
Joined: November 4, 2000
 Ok I think I figured it out. Apply 5 volts onto the 2 outer pins of the points into the USB out on the Regen mobo. I guess I could use my 2nd Regen as the source. What do you think?

Btw soldering helped plus putting on a trickle charger actually made the little Amber light brighter and the sound a bit better. So I am guessing my charge was a bit low on the batteries.

 

RE: Improved Regen sound, posted on November 23, 2015 at 07:26:31
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 Do you have a clean 5V supply? You could connect this to the USB output on the Regen?

 

RE: Improved Regen sound, posted on November 23, 2015 at 08:07:05
theob
Audiophile

Posts: 3180
Location: ann arbor michigan
Joined: November 4, 2000
 Ok I played around with acoustically isolating the 2 battery cell and whoa more delicacy/depth/hall sound. Funny once my cell of batteries was fully charged the charger pilot light turns green and wow it sounds good. I have a few files which are my test music and yes they never sounded so good. A complete success with more to go.

 

RE: Improved Regen sound, posted on November 23, 2015 at 08:23:12
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 Yes that's a good plan -just make sure you have the polarity correct :)

Connecting The charger shouldn't result in a brighter led - as you say your battery probably was low - leave it on trickle charge overnight.

 

RE: Improved Regen sound, posted on November 23, 2015 at 08:28:54
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 Thanks for all the info on various batteries but what we are focusing on here is LiFEPO4 batteries which have a steady voltage of 3.3V until they reach their low charge point when they quickly fall to their minds V of 2.7V

It's important not to confuse this battery chemistry with other s

 

RE: Improved Regen sound, posted on November 23, 2015 at 09:14:29
pictureguy
Audiophile

Posts: 22597
Location: SoCal
Joined: October 19, 2008
 Lithium Iron Phosphate is one of the older Lithium ION batteries.

A search of other chemistries will show many (several?) which have similar discharge curves.

If the voltage does indeed have a REGULATOR, than is doesn't matter as long as the voltage is a certain amount OVER the desired regulated voltage. Did I read some complaints about noisy regulators in this thread?

Some of the newer chemistries are available in size '18650' of which the Tesla uses THOUSANDS per auto and are maybe the swiss army knife of batteries. Available now in up to 5000mah with stable voltage during much of its capacity. Voltage starts at 3.7v

The reason I suggest that particular cell, is that you can buy 'em WITH a little charger, keep a spare pair charged so you NEVER go flat and the low self-discharge means long shelf life. i do not know the spec for internal resistance or any noise issues with this cell.
Too much is never enough

 

RE: Improved Regen sound, posted on November 23, 2015 at 10:06:22
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 Thanks again, Pictureguy, you seem to have a good knowledge of battery chemistry. What we want to avoid is a regulator on the battery output. Can you nominate any others that have 3.3V output & a similar discharge curve to LiFePO4 batteries?

Regulation from my experiments so far, have proven to be noticeably detrimental to the sound when compared to using power from the batteries directly.

I've mostly used these batteries on digital ICs which require 3.3V power. I'm not sure if it's the low noise (especially at LF) or fast transient response that accounts for their advantages in this role? The only regulators which seem to come close to these batteries are the Paul Hynes ones so it's possible to build. He has different regulators for different roles, digital or analogue power, low current or high current & he emphasises transient response for digital but I would also add low noise at low frequencies as also being important for clocks, etc. These batteries seem to check both of these boxes

I've also tried them on smallish, chip-based power amplifiers & the improvements were also noticeable

 

RE: Improved Regen sound, posted on November 23, 2015 at 12:02:06
pictureguy
Audiophile

Posts: 22597
Location: SoCal
Joined: October 19, 2008
 I'm getting out of my depth, but have you considered fabricating a DISCRETE regulator? Maybe thru the use of a Zener Diode?
I'm certain that someone who KNOWS can help you with this.

As for batteries? You'll have to go to the next level thru some research.
As a start? Simply GOOGLE 'lithium battery' or 'lithium ION battery'. The Wiki would be where I'd start. Keep in mind that things change LOTS and quickly, so such articles may not be up to the second.


Too much is never enough

 

Inmates: Play at your OWN RISK...., posted on November 23, 2015 at 12:26:03
AbeCollins
Audiophile

Posts: 46295
Location: USA
Joined: June 22, 2001
Contributor
  Since: February 2, 2002
 These batteries are capable of supplying a ton of instantaneous current. Careful handling and a fuse wouldn't be a bad idea.


 

RE: Improved Regen sound, posted on November 23, 2015 at 12:47:00
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 Huh??
You seem to have the wrong end of the stick, here.
Why do you think I might want a discrete regulator - these batteries perform better than any regulator I've tried - the only regs that come close are the Paul Hynes ones which are very much more expensive than a battery.

Thanks for all your input on batteries so far but I was hoping you might have been able to answer the question I asked - what other battery chemistry will give 3.3V & the same discharge slope as LiFePO4? I'm not particularly looking for a replacement for LiFePO4 batteries but as you say yourself - with regard to information "Too much is never enough"

 

The question is:, posted on November 23, 2015 at 13:08:44
fmak
Audiophile

Posts: 13158
Location: Kent
Joined: June 1, 2002
 what constitutes an improvement in SQ and is a battery really better than a good regulator?

When feeding a circuit with a battery, there is self noise from the battery itself to consider, if there is no further bypassing. There is little information of practical use in audio that I can find wrt LiFePO4 battery noise in this regard.

I don't think that one can say for certain that battery power is always superior.

I was in a dealer demo room which had several LiPO powered usb to I2S hdmi converters lying around. I asked why and was told that that the batteries had all failed. This was in spite of a clever self activated inbuit charging circuit.

The manufacturer has recently abandoned this design and had gone over to dc power, with an expensive super capacitor reservoir unit as an accessory!

When one trickle charges a battery which is providing power, there is the situation where discharge and charge chemistries are taking place at once. Is this good? Who knows.


 

RE: The question is:, posted on November 23, 2015 at 13:42:08
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 "what constitutes an improvement in SQ and is a battery really better than a good regulator?"

Your question would be answered by listening!

"When feeding a circuit with a battery, there is self noise from the battery itself to consider, if there is no further bypassing."

At such low currents as are drawn by digital ICs (usually in mA), the self noise is likely to be very minimal from a battery that can deliver 60Amps continuously & 120Amps instantaneously.

"When one trickle charges a battery which is providing power, there is the situation where discharge and charge chemistries are taking place at once. Is this good? Who knows."

Try it & see if it affects SQ.

As to long term reliability of batteries - just look at electric vehicles which use exactly the same batteries - are they reliable?

But I like your approach to issues - look for the weaknesses first - it's the approach I use too!

 

Wondering about that existing regulator, posted on November 23, 2015 at 14:42:43
rickmcinnis@dogwoodfabrics.com
Audiophile

Posts: 3040
Location: Atlanta
Joined: December 15, 2003
 So the battery will be powering the circuit and the existing regulator.

Could there be an easy way to take the reg out of the circuit?

One wonders if the thing would sound better if it wasn't in the circuit?

Of course, we should be happy with what we have but what fun it that?

 

RE: Improved Regen sound, posted on November 23, 2015 at 14:54:40
chopper87@aol.com
Audiophile

Posts: 942
Joined: September 2, 2001
 jkney,

So, those of us who have DACS, like my Auralic Vega, which requires a 5 Volt
Hand Shake for turn on only, then NO 5 Volt through the USB cable, will still need to use the external power supply and the bypass battery?

I am currently using a very nice power supply into the Regen;s stock power input connection. This supply made an obvious sonic upgrade to the Regen,s performance. So, am I correct that I will need the addition of the ground and 3.3V connection to bypass the stock regulator?

Lance A.

 

RE: Wondering about that existing regulator, posted on November 23, 2015 at 15:06:13
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 No, the battery is on the output of the regulator - it's not powering it.
Don't power the Regen & the regs are turned off

 

RE: Improved Regen sound, posted on November 23, 2015 at 15:16:24
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 I believe at least some percentage of the improvements reported with the Regen are due to a cleaner 5V supply into audio devices that use the 5V (even for just signalling).

If you can disconnect the 5V after your Vega handshakes with the Regen & everything operates fine then why not proceed as follows:
- connect the LiFePO4 battery as I suggested
- power your Regen with your PS as usual
- when handshake established with Vega, disconnect your PS to the Regen (leave battery connected)

If you want a procedure that requires less manual intervention, you can get one of the USB solutions that provide external 5V substitution for Vbus (like Aqvox) or go the DIY route & provide 5V to the correct pins on the Regen's USB out

 

RE: Improved Regen sound, posted on November 23, 2015 at 16:23:42
pictureguy
Audiophile

Posts: 22597
Location: SoCal
Joined: October 19, 2008
 This'll be my last post on the subject.

PLEASE, by all and any means, try the WIKI on Lithium Batteries. Find a cell with higher than required voltage and Than see if you can dig out the discharge curve. I've got lots on my plate (so to speak) and while I'd love to get into the minutia of your dilemma, I simply don't have the free time.

A few sources for discrete regulator information may be either DIY Audio or perhaps Elliot Sound Products. Paul Hynes didn't INENT this category, but does it well.

If you are interested in 3.3v OPEN CIRCUIT, I don't offhand know of an exact match. Some are higher, some are lower.

Knowledge of the tolerance of the circuit may also help choose a battery. Some electronics may work at -+0.2v given a 3.3v nominal. Something along those lines:
Too much is never enough

 

RE: Improved Regen sound, posted on November 23, 2015 at 16:26:18
chopper87@aol.com
Audiophile

Posts: 942
Joined: September 2, 2001
 This is exactly the clarity of advice that I was hoping for. As I design and build all of my own cables I use a dual Type A USB cable. Once the hand shake is establish, then I disconnect the 5 Volt connection via the one USB Type A leg. Makes for a substantial sonic upgrade.

Any specific gauge of wire suggested for the 3.3 Volt/Ground connections to the battery supply? I assume that you simply make a small cable hole through the Regen's case and then return it's case to it's original position?

Last, As I was not around for the original discussion about the battery supply recommended, can you please tell me what battery supply to purchase and possibly where to make purchase?

Thanks a bunch.

Lance A.

 

RE: Improved Regen sound, posted on November 23, 2015 at 16:43:30
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 Hey pictureguy, again you seem to have the wrong end of the stick - maybe you are reading too fast & not comprehending? Your replies, although they seemed to promise a knowledgeable source of information on batteries, now seem more confusing than enlightening.

I don't have ANY dilemma - I find the LiFePO4 batteries perfect for my requirements & perfectly suited to the PS roles I have used them in. A 3.3V open-circuit is perfect using these & provides substantial advantages.

I don't believe there are any alternatives which match the characteristics of LiFePO4s & you seemed to hint at knowledge of this area but no worries.

Thanks anyway for your input

 

RE: Wondering about that existing regulator, posted on November 23, 2015 at 16:45:47
theob
Audiophile

Posts: 3180
Location: ann arbor michigan
Joined: November 4, 2000
 Btw I'm still using double Regens but since I charged up the batteries,isolated the batteries from aucustic feedback the Sonics are to die for. Depth, dynamics, low-level detail and delicacy of the highs (especially strings, guitars,mandolin) are really good.Thanks Jkeny. I"m going to listen for a few days before I go single Regen.

 

RE: Improved Regen sound, posted on November 23, 2015 at 16:48:04
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 I'm suggesting testing this first with whatever wire you want to prove it's sonic value

Figure out how best to case it back into it's original casing later

You will have to read through this thread - all the information about battery type & where to buy is in there

 

RE: Wondering about that existing regulator, posted on November 23, 2015 at 16:50:23
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 Cool!

Yes, try the single Regen at some point & let us know any difference!
You might then have a spare Regen for sale :)?

 

RE: Improved Regen sound, posted on November 23, 2015 at 17:18:31
pictureguy
Audiophile

Posts: 22597
Location: SoCal
Joined: October 19, 2008
 You want someone to TELL you what you need to know.

I want, or would desire you, to do some research. Everything is out there for your reading pleasure.

If you are happy with the current (no pun intended) situation, why bother to write?


Too much is never enough

 

My Regen would sound a HECK of a lot better..., posted on November 23, 2015 at 17:29:04
Ivan303
Audiophile

Posts: 48887
Location: Cadiere d'azur FRANCE - Santa Fe, NM
Joined: February 26, 2001
 If UpTone would freaking SHIP the one I purchased from them and that they charged to my CC a month ago.


Just sayin'.


First they came for the dumb-asses
And I did not speak out
Because I was not a dumb-ass

 

RE: Improved Regen sound, posted on November 23, 2015 at 18:24:58
chopper87@aol.com
Audiophile

Posts: 942
Joined: September 2, 2001
 For those of us who have a JITTERBUG plugged into our DAC after (piggy backed onto the Regen), does that mean that the Jitterbug needs the 5 Volts that I am eliminating to work. Or is the 3.3 Volts from the battery enough to power the Regen and the Jitterbug?

Lance A.

 

RE: Improved Regen sound, posted on November 23, 2015 at 20:36:26
Bob_C
Audiophile

Posts: 2667
Location: NY
Joined: July 31, 2000
 You might not know who JK is. I think he REALLY knows what he is talking about, and does not need any help. :)

Since you posted the in depth post on batteries maybe it was thought you had a direct relationship with the Energizer Bunny and could reveal some trade secrets, not just reference Wikipedia.

Regards
Bob

 

RE: Inmates: Play at your OWN RISK...., posted on November 23, 2015 at 21:24:22
kenzo
Audiophile

Posts: 955
Location: San Francisco
Joined: September 27, 2003
 Did you see the Bear Gryllis show where he took the battery from a cell phone, stabbed it a couple times and then shorted it with his knife to start a fire. I think he was in Iceland.

Tiny little battery burned like a road flare!

 

RE: The question is:, posted on November 23, 2015 at 22:08:43
fmak
Audiophile

Posts: 13158
Location: Kent
Joined: June 1, 2002
 I have ordered the batteries you suggested, but this doesn't stop the mental questioning. Battery noise is not a function of battery capacity and is a function of chemistry; the smaller the current draw, the more significant it is likely to be as a percentage of output.

How long does one of your recommended batteries last if one does not trickle charge?

 

RE: Inmates: Play at your OWN RISK...., posted on November 24, 2015 at 00:20:33
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 Not the same battery chemistry - no risk of fire or battery explosion with LiFEPO4

 

RE: Improved Regen sound, posted on November 24, 2015 at 00:22:01
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 Wow, you really do not comprehend my post sor what the thread is about, do you?

 

RE: The question is:, posted on November 24, 2015 at 00:31:14
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 "I have ordered the batteries you suggested, but this doesn't stop the mental questioning. Battery noise is not a function of battery capacity and is a function of chemistry;"
It's a function of both - look at the TNT you alluded to about battery noise

" the smaller the current draw, the more significant it is likely to be as a percentage of output."

You can keep doing mental questioning but why not wait until you get the batteries & your questions will be answered empirically?

"How long does one of your recommended batteries last if one does not trickle charge?" I haven't tried one on the Regen but you can figure this out mathematically or empirically

 

RE: Improved Regen sound, posted on November 24, 2015 at 00:33:01
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 The Jitterbug is a passive device - it doesn't need power!!

 

RE: Improved Regen sound, posted on November 24, 2015 at 00:36:30
pictureguy
Audiophile

Posts: 22597
Location: SoCal
Joined: October 19, 2008
 Sure, easy.
You don't like regulators and have replaced it with a battery which to you sounds much better.
So what? You mentioned some guy who I looked up and he does make some neat looking discreet regulators. You said they were too much $$, even though a fixed cost rather than a recurring cost of battery replacement and the hassle of recharging. I get the impression you think THOSE sound OK, or is that mistook?
Now what?

Too much is never enough

 

RE: Improved Regen sound, posted on November 24, 2015 at 00:43:01
pictureguy
Audiophile

Posts: 22597
Location: SoCal
Joined: October 19, 2008
 Wouldn't know JK if he ran over me in a crosswalk. Am I supposed to know him?
I was trying to simply help him find a better battery. Battery measurables include internal resistance and of course the voltage / output curve which for JK's purposes, needs to be as flat as possible. Given the huge number of Li and Lion chemistries, I'm not about to plow thru it looking for what is probably a marginal improvement, though you could get lucky. The battery chemistry which JK uses is from the 'dawn' of the Lithium technology and may have been bettered in ways that matter to HIM.

Too much is never enough

 

RE: Improved Regen sound, posted on November 24, 2015 at 01:11:05
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 Where did I say I was looking to find a better battery??

 

RE: Improved Regen sound, posted on November 24, 2015 at 01:14:05
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 So this is why this place is called the "asylum" !!

 

RE: Improved Regen sound, posted on November 24, 2015 at 03:06:38
theob
Audiophile

Posts: 3180
Location: ann arbor michigan
Joined: November 4, 2000
 More subjective comments: after listening for 7 hours I am convinced that timbre has never been better in my system. This is especially noticed on good piano recordings. Almost lost is the superb bass: tight yet full. The other thing is air around everything. It is really enjoyable to have such a major impact on sound from just knowledge (thanks Jkeny) and minimal work. Can a single Regen be even better?

 

RE: Improved Regen sound, posted on November 24, 2015 at 03:22:35
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 Thanks for the reprt, Theob - yes they are all the SQ characteristics that I have heard with this tweak.

Can a single Regen can be better? I suspect so but only trying it will sort this out

 

RE: Improved Regen sound, posted on November 24, 2015 at 03:24:20
theob
Audiophile

Posts: 3180
Location: ann arbor michigan
Joined: November 4, 2000
 I will get there its just a matter of time. Other obligations in this US holiday week.

 

RE: Improved Regen sound, posted on November 24, 2015 at 03:42:36
theob
Audiophile

Posts: 3180
Location: ann arbor michigan
Joined: November 4, 2000
 One more comment on the sonics. All instruments seem to emanate from a smaller space within the larger acoustic. As a result the imaging is phenomenal. Especially in a well recorded classical piece. I have one of those Spring music...4 Seasons et al.... files. One cut is a Vivaldi movement for mandolin and orchestra. You can almost guess the distances between instruments. You see the space.

 

RE: Improved Regen sound, posted on November 24, 2015 at 03:57:06
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 Sure, I wasn't pressurising you, just answering your post

 

RE: Improved Regen sound, posted on November 24, 2015 at 04:01:23
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 My theory is that the solidity of the soundscape is the result of the lower low frequency noise of the battery & the resultant lower close-in phase noise of the clock but it's only a theory

 

RE: Improved Regen sound, posted on November 24, 2015 at 05:37:55
chopper87@aol.com
Audiophile

Posts: 942
Joined: September 2, 2001
 Ah, never really looked too deeply into the Jitterbug's power scheme. Thought maybe it used the USB 5 Volt line to operate. Totally passive though. Good to know. Thanks.

 

But with my computer battery supply, posted on November 24, 2015 at 08:32:47
rickmcinnis@dogwoodfabrics.com
Audiophile

Posts: 3040
Location: Atlanta
Joined: December 15, 2003
 If I do not disconnect the batteries from their respective "float charger" the AUDIOWIND LEDs will continue to be lit.

I figured the same thing would happen here.

Obviously not a problem but more audio speculation as to whether it makes any difference.

Not that I have any intention of removing that regulator ...

 

No risk of fire? Really ?, posted on November 24, 2015 at 08:45:43
AbeCollins
Audiophile

Posts: 46295
Location: USA
Joined: June 22, 2001
Contributor
  Since: February 2, 2002
no risk of fire or battery explosion with LiFEPO4

So you mean to say a battery that can source current in the 10's of Amperes is not a fire hazard? I suppose the battery itself might not ignite but we're talking about current that can melt wire insulation and can even weld metal.




 

RE: No risk of fire? Really ?, posted on November 24, 2015 at 08:58:11
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 Do you want the truth or just want to be pedantic & argue?

The particular formulation of Lithium within LiFePO4 batteries is far more stable than the Lithium batteries that have "scare" stories about them blowing up or catching fire from overcharging.

Kenzo's Bear Gryllis story was comparing apples & bananas.

Of course, there's no accounting for stupidity & I'm sure certain people could find a way to blow them up - by putting them in their microwave, for instance - just as they can blow up their pets by doing the same thing! But that doesn't mean that their pets are a fire hazard

 

RE: Inmates: Play at your OWN RISK...., posted on November 24, 2015 at 09:04:20
Ryelands
Audiophile

Posts: 1867
Location: Scotland
Joined: January 9, 2009
 no risk of fire or battery explosion with LiFEPO4

Hmmmm. A friend of mine, a more than competent technician, a year or two back popped an ordinary 9v alkaline battery into his trouser pocket. It shorted on his keys and gave him a nasty burn on the thigh. As he ruefully told me, he knew immediately what he'd done but that wasn't much consolation.

Fire hazards posed by commonplace batteries are well documented.

D

 

RE: Inmates: Play at your OWN RISK...., posted on November 24, 2015 at 09:22:11
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 I know somebody who put his tongue on a frozen pole, once with nasty consequences!

I would suggest that he doesn't attempt this tweak, either.

 

THE TRUTH, posted on November 24, 2015 at 09:24:07
AbeCollins
Audiophile

Posts: 46295
Location: USA
Joined: June 22, 2001
Contributor
  Since: February 2, 2002
 Not being pedantic & argumentative. Just pointing out safety concerns that you choose to ignore.

You can ignore the TRUTH but it's not about the battery formulation... it's about the amount of current the battery can source. I don't care if it's alkaline, lead acid, nickel metal hydride, etc.

If the battery can source 10's of Ampere's of current then there is a fire hazard and safety concerns... not necessarily in the battery itself but with wiring, handling, metal tools, short circuits, etc.

You yourself stated: "...the self noise is likely to be very minimal from a battery that can deliver 60Amps continuously & 120Amps instantaneously.

That kind of current can be a fire hazard, period.



 

RE: THE TRUTH, posted on November 24, 2015 at 09:28:19
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 Sure, I also said treat them like a car battery & that I started my car off 4 of them in series.

Anybody who doesn't know enough about electricity to know that a car battery should be respected & care taken with it shouldn't be going near opening up an electronic device to tweak it.

Edit: But you are correct to warn about this - I have edited my first post to warn people about the risks, thanks for this heads-up

 

RE: Improved Regen sound, posted on November 24, 2015 at 09:28:41
chopper87@aol.com
Audiophile

Posts: 942
Joined: September 2, 2001
 theob,

I would love to see a photo of your Regen board wired up with the bypass. Not that jkeney's original board photo and very clear descriptions won't get the job done, but things always feel better with a photo of the done deal.

Thanks Guys.

 

RE: THE TRUTH, posted on November 24, 2015 at 10:12:56
AbeCollins
Audiophile

Posts: 46295
Location: USA
Joined: June 22, 2001
Contributor
  Since: February 2, 2002
There are inmates here who don't know the hot end of a soldering iron and at least one who has blown up his Tek oscilloscope by probing around where he didn't belong.

Just want to be safe. I would suggest a fuse somewhere inline with the battery. Just a thought.



 

RE: THE TRUTH, posted on November 24, 2015 at 10:35:14
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 Sure, I've put a warning on my first post

 

RE: Improved Regen sound, posted on November 24, 2015 at 11:50:03
theob
Audiophile

Posts: 3180
Location: ann arbor michigan
Joined: November 4, 2000
 Am having difficulty getting 5 volts to my battery operated Regen. Did you ever listen to a Regen with battery and the 7.5 Volts power plugged in. Is it that much of a degradation in sonics?

 

RE: Improved Regen sound, posted on November 24, 2015 at 13:00:41
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 No, I've never tried that config - battery powered Regen + Regen being powered from DC input.

Your config is:
- battery powered Regen
- feeding another Regen which is DC powered

My conjecture was that bypassing the regulators in the battery powered Regen either reduced low frequency noise and/or improved the transient response of the PS.

So putting a DC input powered Regen after the battery powered one MAY work against these improvements of the battery powered Regen.

But I could be wrong!

 

RE: Improved Regen sound, posted on November 24, 2015 at 13:56:00
chopper87@aol.com
Audiophile

Posts: 942
Joined: September 2, 2001
 I have managed many years without attempting to bypass my preamplifier's, or any other equipment power supplies with Batteries, though I have been tempted. But this seems like the right time to do it since we are dealing with such small voltages.

However, I have rather limited knowledge of batteries and chargers. I will have no issues finding the suggested 3.3V LiFePo4 batteries, but what amperage, or MA output capable should these batteries be capable of and what type/size trickle charger is best for this procedure?

If this upgrade is close to as good as claimed, then you are owed much thanks.

Thanks

 

RE: Improved Regen sound, posted on November 24, 2015 at 14:21:51
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 The batteries are LiFePO4 (Lithium nano Ferrous Phosphate) which have a voltage of 3.3V (not 3.7V) & have a battery size known as 26650

You don't need a special battery charger - just a regulated supply that outputs 3.3V or 3.4V. Permanently connected to the battery it trickle charges it & there's no overcharging

 

RE: Improved Regen sound, posted on November 24, 2015 at 15:01:36
chopper87@aol.com
Audiophile

Posts: 942
Joined: September 2, 2001
 Thank you very much. As my big Lambda power supply improved the sound through my Regen when compared with the stock wall wart, then I expect your solution to be even better. Thanks again.

Lance A

 

RE: No risk of fire? Really ?, posted on November 24, 2015 at 16:04:44
Bob_C
Audiophile

Posts: 2667
Location: NY
Joined: July 31, 2000
 "" But that doesn't mean that their pets are a fire hazard""

What if you cat in a pyromaniac?

Certain individuals just love to be negative.








 

RE: Improved Regen sound, posted on November 24, 2015 at 16:06:33
theob
Audiophile

Posts: 3180
Location: ann arbor michigan
Joined: November 4, 2000
 No offence taken.

 

RE: Improved Regen sound, posted on November 24, 2015 at 16:35:47
theob
Audiophile

Posts: 3180
Location: ann arbor michigan
Joined: November 4, 2000
 Send me an email

 

RE: Improved Regen sound, posted on November 24, 2015 at 19:11:56
chopper87@aol.com
Audiophile

Posts: 942
Joined: September 2, 2001
 Chopper87@aol.com

Thanks a bunch! I just finished ordering some of the batteries and an appropriate charger. Your photo/s will help my confidence that I am doing it correctly.

Lance A

 

RE: No risk of fire? Really ?, posted on November 25, 2015 at 01:48:08
fmak
Audiophile

Posts: 13158
Location: Kent
Joined: June 1, 2002
 There is always a risk of tire even when one puts a power hungry cpu powered by a kW smps, which is directly connected to the mains (without an isolation transformer).

It is up to diy individuals to find out and know what they are doing.

The negativity comes from a small group who don't want to hear that SQ can be improved easily and safely.

Just have a fire extinguisher nearly!

 

the regulator is a limiting factor, posted on November 25, 2015 at 07:30:32
fmak
Audiophile

Posts: 13158
Location: Kent
Joined: June 1, 2002
 The power supply into the Regen is also a limiting factor.

Whilst waiting for the delivery of a LiFePO4 battery and a charger, I have by coincidence also been testing various forms of power supply into the Regen.

1. Terdak 9V into a TPS demo regulator set at 7.5 V output into the Regen.a The sound is OK but lacks the dynamics and resolution of a truly good system. Bass is somewhat loose.

2. SMSL 9V into the same system as above. SQ is much improved and a pleasure to listen to.

3. 5200 mAH LiPO battery direct into the Regen. Bass and mf + lf better resolved but slightly lacking in musicality of system 2. Bass is firmer though.

This SQ characteristic of the Regen needs to be qualitfied by the choice of LPS into my CI329 PC. Worst off is a 10A lab supply available on Amazon and elsewhere. With an extra 10000uF of added capacitance plus other hf bypasses, SQ is fine in the absence of a better LPS.

With a Paul Hynes 2.2A Shunt supply. Sound is musical and sound stage wide and deep but a little 'yang'. The overall sound is rather different from that from the lab supply and as different as using different supplies into the Regen. I shall need to reduce the standing current to about 1A for this shunt supply and listen again, not liking the very high component (50 to 70 C) temperatures when all that is needed is about 10VA or less.

With a Chinese 8A superegulator with R Core transformer (not the LT 19xx chipped variety) SQ is excellent, and even better when I bypassed the output with high quality hf capacitors built into the output silver coated ptfe power cable.

So the change in SQ using different power supplies into your PC is as much as that which can be obtained thru playing with the Regen power supply.

Hence my comment that it is difficult to say which tweak and which setup produces the best SQ. In fact, disabling the Windows Management Instrumentation Service in my audio PC giving the Player software real time priority causes as much change in SQ as other tweaks done without!

 

RE: Improved Regen sound, posted on November 25, 2015 at 07:36:09
Tony Lauck
Audiophile

Posts: 13629
Location: Vermont
Joined: November 12, 2007
 My REGEN worked when fed with 5 volts. I didn't realize that the power source was only outputting 5 volts so I wasn't looking for a sound quality difference, but if there was one it certainly didn't jump out. (This is with an unmodified Regen.)

If you have multiple devices wired into a chain between the computer and the DAC there are lots of combinations to try! More combinations than time, ...

Tony Lauck

"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar

 

RE: the regulator is a limiting factor, posted on November 25, 2015 at 07:39:32
Tony Lauck
Audiophile

Posts: 13629
Location: Vermont
Joined: November 12, 2007
 One thing to consider is that measurements have shown that noise on the REGEN power can couple into the analog output of some DACs. This appeared when the DAC was running in unbalanced output mode, but did not appear when the DAC was running in balanced output mode, presumably because of common mode rejection in the downstream device.

Were you running balanced or unbalanced? It may be that running balanced mode out of your DAC into your (pre)amp may make things less critical.

Tony Lauck

"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar

 

RE: THE TRUTH, posted on November 25, 2015 at 07:48:12
Tony Lauck
Audiophile

Posts: 13629
Location: Vermont
Joined: November 12, 2007
 "There are inmates here who don't know the hot end of a soldering iron "

Been there, done that. That was a painful lesson. Also managed to touch an RF antenna coupler handling 1 KW at 7 Mhz. This was not painful in the least, and I didn't notice anything until I smelled burning flesh. Fortunately, there was no significant damage. Worst, I somehow managed to touch the secondary of a neon sign transformer, or at least that's my theory. I don't recall the details, just coming to in a pile on the opposite side of the room. (These events were more than 50 years ago.)

Tony Lauck

"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar

 

RE: Improved Regen sound, posted on November 25, 2015 at 08:03:47
Tony Lauck
Audiophile

Posts: 13629
Location: Vermont
Joined: November 12, 2007
 I don't doubt the perceptions, but the theory seems somewhat incomplete. The problem is that the clock is the USB bit clock. Phase noise has nothing to do with phase noise modulating the audio clock, because this clock is at a totally unrelated frequency. A possible theory might add that the regulator noise caused jitter in the USB bit clock affects the USB receiver circuitry's power consumption. This is related to John S's theory of how the REGEN works to improve sound quality, but as far as I know this is just speculation as there is no hard evidence of what is going on.

We do know that noise on the REGEN power can be coupled into the analog output of some DACs in the form of common mode noise. This noise appears at the packet clock rate (8 kHz), indicating that the regulation isn't sufficiently stiff.

It beats me why DAC designers don't deal with these issues. There is no excuse for any 8 kHz noise to appear in the output of any USB DAC, regardless of the input signal, assuming only that the input signal conforms to the USB specification.



Tony Lauck

"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar

 

RE: The question is:, posted on November 25, 2015 at 08:18:04
Tony Lauck
Audiophile

Posts: 13629
Location: Vermont
Joined: November 12, 2007
 "I have ordered the batteries you suggested, but this doesn't stop the mental questioning. Battery noise is not a function of battery capacity and is a function of chemistry;"

It appears that larger capacity batteries of the same chemistry have lower noise. This is what one would expect. Simply paralleling identical batteries will reduce the noise due to cancellation.

A little googling found a reference that supports your claim that larger capacity batteries are going to have lower noise.

Tony Lauck

"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar

 

Page: [ 1 ] [ 2 ]

Page processed in 0.054 seconds.

[ Top Top of Page ] [ Contact Us ] [ Support/Wish List ] [ Copyright © 2024, Audio Asylum, all rights reserved ]
[ General ] [ Speakers ] [ Tubes ] [ Vinyl ] [ Digital ] [ Hi-Rez ] [ Video Asylum ] [ Cables ] [ Tweaks/DIY ] [ Music ] [ Films ]