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In Reply to: RE: Best Passive/Active Combination of Crossovers for IIIa's and T 1-D's posted by Satie on July 03, 2015 at 12:30:30
I am actually quite adept at soldering if the instructions are adequate. I have even done surface mount soldering with a magnifier. I built electrical kits way back, and have kept up somewhat with the skill. If I take my time all is well. The DEQX is on my wish list. I will investigate purchasing the parts and download appropriate instructions to see what I would be getting into for the DCX upgrade. That would give me a temporary improvement, while waiting for a good used DEQX to come up.
What is your opinion of the Kenwoods? The plan would be to use them for the mids and the PF-200 for the tweeters and selling the Rotel.
In the interim, I put a test CD on and discovered that phasing is not correct. I tried inverting the separate drivers with the DCX, but with no improvement. I did it individually. I also separated the mids and tweeters using the ADA PF-200 for the mids and the Rotel for the tweeters. That did give improved results.
Follow Ups:
The Linear audio mod Davey favors is the most convenient and provides relative level control in the analog and a general remote vol control using a vol contrl chip.You can probably get the boards and do the installation.
http://www.behringermods.com/dcx2496.html was not mentioned in the URL below
They are the proven audiosmile mods and are sold as DIY kits and would be right up your aley and cheap. There is no vol control mod for the DCX. They use very good op amps, LM4562 and a few other components for the active output.
MSB sells a couple of models of remote controlled multichannel gain and volume control boxes in op amp and discrete component implementations, $1k and $4k (price from memory check first)
Asi Tec Tweakaudio and Reference mods do different mods to the input/output analog sections digital sections and DAC - The tweakaudio mods are available in different combos so you can do a minimal mod of the output stage and DAC sections for not much more than the cost of the DCX. Asi Tec do transformer coupling (those are rather expensive transformers but it is something you can do yourself.
Only the Linear Audio mod adds functionality. It is also less expensive than full on mods of any of the others ($1500-$2500).
Edits: 07/03/15
This is what Simon Ashton wrote when replying to a request for a comparison between his and (the other vendors) mods. I have replaced the reference to the actual name of the other vendors mods with "(other vendors) to be fair...I do appreciate his honesty...
What do you think of his mods, would they be sufficient?
"...The passive output mods offered by (the other vendors) are simply inferior so don't go for those. There are very good reasons why the differential output of the DAC should be summed and buffered.
The active outputs offered by (the other vendor) have a volume control which my mods do not
(although the DCX has gain adjust for each channel as standard). (the other vendors) mods output only single-ended even though they have an XLR socket. My mods are fully balanced and floating outputs, which means even when you use them in single-ended configuration they still offer the noise cancelling benefits of balanced connections (including reduced ground loop noise). Basically the simulate the way a transformer balanced output works, with the advantages of active circuits. My mods use the latest and best op-amps with exceptional signal to noise and distortion performance while the (other vendors) mods use a less than state of the art multi-channel IC. Also note that the active (other vendors) mods need the DCX card reader to be replaced with the LED screen but this card reader has been removed from the most recent DCX revisions."
The balanced trannie outputs of some of the alternatives is fully balanced and remains quiet in conversion to SE with an RCA adapter. So no dice on that.The guys who do cap coupling instead of the active stage or trannie don't really support the balanced mode and would happily replace the XLRs with RCAs.
I will assume that his reference is to the active remote controlled output section from Linear A. There he would be right and his setup would sound better but lack the functionality of the multichannel vol. contrl.. But if you can do well enough without it then forget that. As usual you are trading function for quality with a given price range.
His boards are just cheap and effective with good quality components.
Not sure i understand the first line..."remains quiet in conversation to System Electronics with an RCA adapter..so no dice..."? If they remain quiet is not that what is desired even though they replace the XLRs? Also, though it" would lack the functionality of multichannel volume control..Would it not still maintain level controls on inputs and outputs, and would that be sufficient?
The mods with trannie outputs stay quiet whether you wire them for balanced output or single ended. so the claim for the noise advantage is not universally true.
You have the ability to adjust relative levels in the digital domain on the DCX prior to the DACs. But overall vol control puts you into overload or loss of resolution (usually the latter since the stock DCX is a 10V standard rather than the home audio 1V standard) So as you lower volume before feeding the DCX you will get lower resolution in the AD process. The ideal way to change volumes is with a multichannel vol control and in the analog domain.
If your budget allows then the "purest" way to go is with trannie coupling in and out and a multichannel vol control like the MSB models. Some HT preamps have a multichannel vol control for their multichannel inputs without any processing, but I have not researched this carefully enough to provide you with particular models that do this without too many compromises.
I asked Simon Ashton if his transformers were coupled in and out and his reply was... "The mods are not transformer coupled, they simulate the way that transformers work. When used balanced they are like any other balanced connection but when used single-ended they reference the signal to the ground connection present on the XLR pin 3 connection. Basically, it's a good thing for reducing noise!"
So given that I appear to have the volume control on analog inputs, and I will test it to verify, then the best solution would be to find a vendor that supplies transformer coupling in and out correct?
I was referring to Ashton's competitors doing trannie outputs as opposed to his active outputs.
I think that given your budget and availability of multichannel Vol Cntrl. you should just get the boards for the input and output for the DCX from behringermods.com
It is cheap and good and you don't need the features of the Linear Audio mods with Vol cntrl..Since you can use your TGP-5 for that
I am using the TGP-5 as my preamp. I could I perhaps continue to use the TGP-5 as the preamp with the volume controlled on the inputs, plus use the TGP-5's "fixed main outs" that are line level? Would the signal carry the input volume? I could test it with appropriate cables, or do i need a separate preamp?
It would not be possible to do that with a normal HT preamp as they should be using the same circuit at some point, but perhaps the line/tape output comes out of the selector separately. But most likely it will just cause feedback.
Get a separate preamp with tape/line outputs. It is just going to be used as a selector box so you can just get a unit with good connectors and selector switch - some tube pres can have the remote control selection and tape outs work even when the tube circuits are burned out and not functional. So you might be able to get something cheap.
The tape out is taken right off the selector switch before the input stage and the vol control.
Thanks Satie, you always seem to come up with a solution that make sense. Unfortunately not all of us can afford real high end equipment, and for myself I know I have made some mistakes in purchasing equipment such as amps in the past, but it is all part of the learning process, although sometimes costly. Keeping a positive attitude and not getting discouraged while trying to tweak the best sound out of present equipment can he a challenge in itself. I have toyed with the idea of just selling these as all panels have been factory rebuilt, but I would like to solve the present problem of imaging and getting a decent crossover first. Then I feel I could make a better decision. I also hate to give up the sound of the Tympani bass. I doubt that it can be duplicated easily.
I do thank you and others here for your kind words of encouragement. I will do a search for a tube pre amp, and possibly find something that might even be decent. What do you think of the Nobosould brand. It is fairly cheap, and has some decent reviews. They can be had on Amazon which has a liberal return policy. I have a prime account so i can get it in a couple of days.
Actually, most SS preamps with a tape loop would have the same functionality too. So there are plenty of options.
There are plenty of "obsolete" pre processors with similar connectivity to the TGP-5 with analog control of the multichannel inputs that can be had for a small fraction of the cost of a new device since they are lacking in HDMI or DVI connectors.
I think that the best imaging would be had by setting up the system in the equidistant arc - the problem you have is that it might not leave enough space between the tweeters in your room - but it is worth a try since it is rather easy to reproduce so even if the panels are in the way you can rather easily move them back to the wall and pull them back out to the arc position.
You don't need to wonder about being able to reproduce the T-1D bass panels' performance.as there is nothing other than another Tympani model to provide it at a real world cost. There are Giant Wilsons Focals Magicos and Sonus Fabers and Legacy speakers that can do it - some better some not quite there - but they don't sell in same order of magnitude in pricing and you can't really move them. These are $10k and up on the used market and outside of the Legacy models all are multiples of $10k.
To better understand the signal path could you please explain? I would use the TGP-5 analog only bypassing the DSP, then how does the separate selector switch/pre-amp come into play? Presently I am using the main outs from the TGP-5 to the DCX inputs.
Sources would be connected to the preamp. You would follow with the passive switching portion of the (new) preamp. You take the output from the tape (line) outs of the preamp to the (analog) input of the DCX. The multichannel outputs of the DCX go into the "direct" multichannel inputs of the TGP-5, and from the multichannel (direct) outputs of the TGP-5 to the individual power amps.
Does that make it clear or did I make it worse?
Satie I received the Emotiva DMC-1 and except for it being a little dusty it is in near perfect shape. Reviewing the connections you recommended, I would request a bit of clarification. For the connections to the DCX2496 from the Emotiva which is the new switching uint, would't we want to go from the main line level audio outs rather than the tape out? I could then also use XLR cables rather than RCA. If not what is the purpose of using the tape out rather than main audio line level out? thanks!
The tape out is to avoid any internal circuits as tape out generally simply taps the switch output and does not even go through the input stage.
Your vol control is on the second unit doing vol control on all the dcx2496 output channels at once.
If you go through the regular main outs then you are adding the input stage and vol. control and active output which are just unnecessary circuits. Unless the sources you have end up needing a boost to get the signal high enough for the DCX AD input circuit.
Satie, I wanted to thank you again and update you on the progress of this project. I received the DMC-1 and connected it as my TGP-5 was. It fired right up and works extremely well. It almost sounds better than the TGP-5. Perhaps it is newer and has fresher parts? Not sure on that one. In any case it is a duplicate in terms of remote and operation so it was a no brainer as far as programming-setup goes. Now I have to make some cables. I posted a link in my previous post in this thread, of the RCA plugs that I have. I have two sets. I also read in the reviews that these plugs are kind of thick and will not fit will on all units especially if the jacks are close. Do you have a preferred plug to use to make some cables, and what cable would you use that is reasonably priced? I know one can spend a fortune on cables but I am not that one. I was thinking about $20 or so for the plugs and matching quality cable. I spoke with the gentleman from Apex Jr.and he recommended 20 Gauge PTFE silver plated stranded copper, but it would be stiff. I have purchased wire from him before and it is excellent quality and very reasonably priced. I made some cables for my mids using his wire and they are excellent. It is one choice, and I am sure you have more. Please advise if possible.
I am a fan of the 20g SPC twinax cable
It is slightly to the bright side so fits well tonally with tube equipment.It is not my first choice for bass ICs but is tight.
I ground the shield only on one end and cut it off the other. I mark that end with the ground. In your grounding scheme that would be either at the source - if your sources are all grounded or at the preamp (which is what I usually do as it has its own ground so I can disregard what sources might not have a ground. In your case the TGP-5 is likely the better place to ground.
I like to use them with screw on locking RCAs or XLRs or light gauge DHL silver RCAs or knockoffs.
The Cardas Rhodium on Silver is the most I would spend on RCA connectors appx $50 per 4
http://www.partsconnexion.com/product7463.html
The Onix and Dayton (parts express) and Connex WBT knockoffs are good
On the really cheap side there are practical amphenol RCAs simple and sturdy no idea what they sound like but have minimal metal - which can be a plus.
These Neutric pros are nicely engineered and have a reputation for a darkish tone in case you need it. The twinax SPC is more white balanced and fills out the top octave more so than a neutral sounding cable. So this might be a better choice if your setup tends to sound bright or even white..
http://www.parts-express.com/neutrik-nf2c-b-2-profi-professional-rca-plug-pair--092-114
Blue Jeans cable make a digital 70 ohm cable with appropriate 70 ohm connectors that also serve as very good analog interconnects Particularly recommended for bass duties, where they are slightly tighter than the JPS superconductors
To get better bass from these SPC twinax use two runs and connect the ends of the lives of each pair and the neutrals of each pair and the shields of each pair. Do not connect the shields to the connectors, leave them to float.If you get hum then connect a drain wire to the shield at the end where your ground is (presumably the tgp 5) and attach it to the RCA neutral there or to the phono ground or body - whichever eliminates the hum..
In most connectors you will want a spacer made of a stiff but still flexible plastic - a dense foam PE or a polystyrene or PET would work. avoid vinyl.
Satie after careful consideration i have decided to go with the Parts Express Locking solder type connectors http://www.parts-express.com/parts-express-audiophile-locking-rca-connector-2-pair--091-1065 as I already own 4 of them, so cost is a factor and I think the quality is sufficient. The only complaint I have seen on these is a lack of instructions, and 8.3mm cable jacket requirements, but with the twinax I don't think that is a problem. Belden has one, if this is what you are referring to http://www.parts-express.com/belden-brilliance-8412-20-awg-2c-mic-line-instrument-cable-tinned-copper-braid-shield-per---102-1250 If you check the connectors out they have a "tang like" connector for the ground, so I assume that one would compress this on the shield? Perhaps you might offer some advice there. If these are not workable then I move to the Neutrik Profi or the screw type that you recommended, but that means the cost goes up. With the mods to the DCX I need to keep the cost down while seeking the best bang for the buck. I like the SPC twinax 20 AWG but I don't need the "bright side" as my setup tends to be on the bright side. I think something smack dab in the middle of the spectrum would suit me better as far as cabling goes. Have you ever used the Canare LT2S? http://www.canare.com/ProductItemDisplay.aspx?productItemID=57 This was highly recommended on The Home Theater Shack cable tutorial. Any further feedback would be greatly appreciated of course. You can also be assured that by the level of advice I have received here that i will do my best to participate in this forum and hopefully pass on some of what i have learned over the years by experimenting and talking with you guys. I love this place! :)
I have not used this Belden twinax but it seems ok. I suggest you read up a bit on what it sounds like since its inductance is on the high side. You need to know that the cable works for your single ended line level purposes.
No problem with using the PE locking RCAs. I use them too.
I did some more searching on this site of your previous posts concerning interconnet cable and found it on ebay.....20 AWG shielded twisted pair SPC... all parts and cable ordered thanks once again!
I thought you had Apex Jr lined up and its teflon mil spec SPC twinax was right in the field of vision on their site.in the 22 gauge at least.
I guess it is better you found the 20 gauge as it is more likely to be less bright.
Got the wire and the RCA plugs...looking forward to assembling some interconnects. You mentioned a spacer. I am not sure what you meant by that...do you have a link to one? In addition is there a way to terminate the cable end of the connector so that it looks neat and tapers to the wire...kind of like this.... but to the cable part of the RCA plug, so that it gives some strain relief and looks good.....https://www.parts-express.com/cable-pants-6mm-2-conductor-black-10-pcs--082-772
Thanks again!
First, don't get those.
The spacer is intended to address exactly this problem of a rather thin cable going into a connector designed for a coax. The solution is to use a spacer that will combine with the cable to create a shape like a coax so allow the set screw ( which does the strain relief ) on the connectors to get a good grip on the cable.
My favorite solution is 1/2 inch segments of the hard jacket peeled off of cheap RG something coaxial cable. Or alternately an appropriately sized cylinder shaped hard rubber (Poly propylene or polyethylene or like) to plug in the free space.
If you want to make it look nice then use heat shrink over the spacer and wire portion and back down to the cable before it enters the connector.. I don't do that since I like to keep the options on the designated use of the wire open.
I found a spacer material from some wall wart extender cables that almost appears to have been made for this wire. The inner diameter is perfect and so is the outer. I will post a step by step assembly procedure for these interconnects as I think it would be helpful, complete with pictures. I would like to add a "shiny/glossy" heat shrink tubing to the finished product for looks and to ID the cables better. A problem I am running into is finding a 3/8" or 9mm I.D glossy red and black heat shrink tubing that comes in a 3:1 ratio as that is what is needed to shrink to the approximately 1/8" O.D. of the 20 gauge wire. I have some non glossy that will work, but it is not near as pretty as the glossy. :) Any suggestions or links to a 3:1 glossy/shiny heat shrink tubing would be very helpful.
I never used a glossy heat shrink so can't help you sourcing it.
How about putting a layer of poly gloss lacquer on the plain heat shrink when you are done?
Satie..I have one question. As the signal path from the XLR and RCA outputs on TGP-5 is no different according to the manual, doesn't it make more sense to use the XLR outs for noise/hum cancellation. The manual states that they are both line level outputs and recommends of course, the use of XLR when possible. In this scenario, to refresh your memory, the TGP-5 outs are going directly to the amps. I am constructing the cables and I have purchased enough XLR connectors to get the job done using them. If I were to use RCA I would need to exchange the XLRs for RCA plugs. Of course I will do that if necessary.
Does the TGP 5 also have multichannel XLR inputs?
If it is indeed the same signal then you can use the XLR option.
Generally speaking I don't like using balanced connections with internally unbalanced gear because of the need for an extra active circuit or transformer to drive the balanced signal. If the amps are not internally balanced as well, then you have just added two stages to the signal path. So unless you have hum problems or have good reason to expect them or are running long cables then stick with single ended unless your devices are internally balanced.
The TGP-5 only has XLR outputs, no XLR inputs. Does that make a difference? The Crest amp uses only XLR connectors. The Rotel and PF-200 use RCA and the PF-200 actually uses phono as it is quite old and most likely a pro amp. I talked to the manufacturer and they said that it was originally quite an amp, priced in the $2500 range, and it is quite pleasant to listen to. Simon Ashton sent a diagram on how to connect an XLR to an RCA plug. Essentially # 1 and 3 to ground on the RCA plug. I will attach the photo, but you are probably familiar with it. From what I can glean from the manual the XLR and RCA outs are the same signal. The description is identical with the exception of recommending XLR for better hum cancellation. I will check the amp manuals to see which ones are or are not internally balanced.
For the bass amp I would not worry about excess active stages and just go with the XLR - I am assuming that would be the balanced only amp. Where the extra active stages make a difference is in the mid and tweeter amps and I understand those have RCA inputs. If so, then connect the mid and tweeter amps with RCAs not XLRs.
If your setup tends to hum much or have much RF, the balanced to RCA is probably not going to help you much with the grounds shorted together- if you need the hum issue addressed then get a balanced to unbalanced transformer to place physically near and before the amps (those are usually designed to work in either direction Bal to SE or SE to Bal). There is a variety of them available on pro audio web shops.
Guess I got confused..anyway the wire I purchased although more expensive is 20 ga. and if it is not as bright as 22 all the better. There is quite a price difference between 22 and 20 ga wire I noticed as well. Must be a lot more surface area.
Sorry I cannot find any 20 AWG SPC cable...must be missing something.
Very well explained thank you!! I am really getting pumped about this. Excellent idea from the get go! Simon is out of parts so I have to wait and I will reorder when he gets them in. In the interim I will get all the cables together and make the ones I don't have. I need some good RCA cables. I have the cabling and two sets of RCA plugs I purchased at Parts Express...http://www.parts-express.com/parts-express-audiophile-locking-rca-connector-2-pair--091-1065. Then all I need to do is to route all the correct signal paths. I have it all on paper now so it makes sense. Thanks again!
That made it very clear thank you! I am looking forward to getting this done. I will most likely be ordering the upgrade kit for the DCX2496 tomorrow. Also
thinking about a cheap Carver preamp like maybe a C-1 or something similar. I would assume the volume pots, switches etc. would be of sufficient quality to eliminate any noise injection providing it is in good shape. Any other brand suggestion?
Look for preamps with gold plated connectors (or the rarer silver rhodium) and no complaints on switch quality (switching noise) - having a tape out, of course.
Old SS pieces that might also be usable with their gain stages are the old PS Audio preamps, Aragon preamps, particularly the 24. The Classe preamps, The Threshold fet 2 preamp, On the cheaper side the Accurus (sp?) 100, Musical Fidelity
On the tube side there are the lower end CJ Manley, VTL Berning and ARC preamps, the Golden Tube Audio pre was cheap and had good connectors. Newer pres like the Doge 8 (used) and the VincentShengya hybrid preamps, There are some passive TVC based preamps as well that should fit your bill..
Again, older HT processors go for rather cheap and may have the right "direct" signal path, high quality connectors and tape/line out. These usually have remote source selection which may be convenient for you.
Either of these would be fine, the TGP III is going to price better, I would guess. There is one on Audiogon for $350 IIRC.
From all I could find the Emotiva is identical to the TGP-IV not the III, so I made an offer on it as I did not want to let this one slip by. It is listed at only $225.00, so even if they don't take my offer it still looks like a good buy and it would fit the bill including remote original box etc.
https://app.audiogon.com/listings/processors-emotiva-dmc-1-essentially-identical-to-sunfire-tg-iii-2015-07-05-home-theater-97405-eugene-or
That is a terrific discount and really looks like the OEM product for both the Sunfire and Emotiva is the same.
Hopefully they don't use lesser parts - not that I have a reason to believe so, just that they have been coming out with new versions of some products with major parts upgrades, e.g. their top preamp.
Well they accepted my offer of 200 plus 55 shipping so definitely a good deal and thanks so much for the guidance!!
Congrats on the new toy.
Thanks did you see this one, even better price and not a bidding situation like the Sunfire. is the quality as good with the Emotiva?
https://app.audiogon.com/listings/processors-emotiva-dmc-1-essentially-identical-to-sunfire-tg-iii-2015-07-05-home-theater-97405-eugene-or
This Aragon would fit the bill correct? plus there is a TGP III for which I have a remote,
http://www.ebay.com/itm/Aragon-Stage-One-Pre-Amp-THX-Ultra2-Certified-With-Pronto-NEO-Remote-/321798526281?pt=LH_DefaultDomain_0&hash=item4aecafd549
TGP III
http://www.ebay.com/itm/291506290787?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT
Would the Sunfire TGP III series fit the bill?...here is an example if the price stays low..only 10 hrs. left http://www.ebay.com/itm/291506290787?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT
I have a remote for it as well as I had to replace mine and could only find a III at the time which also works for the 5.
P.S. I looked further in the manual and it states that "...the 8-channel audio inputs bypass the DSP circuits of the TGP-5 ...provides the highest fidelity signal path...free of any coloration or processor circuitry." Would that provide the multi channel volume control like the example you might be talking about? If that is the case we are golden. :)
YES! looks like you already have that covered so you can do the vol control on the TGP-5 and not on your preamp - you just adjust the preamp to give you the best match to the DCX input to keep it out of overload and at max resolution. You should be able to get the input to just below the 0 db mark on the indicators on the loudest peaks.
On the Sunfire TGP-5 there is a settings area that allows "volume control" of the individual speakers as a whole speaker, for example "left front", "right front", "center", etc., but most likely includes processing and certainly is not input volume control. The TGP-5 does feature a "Direct 2-channel analog bypass mode", and line level stereo RCA L & R out. Perhaps what you might be referring to that may be used is "8 "short analog only signal path inputs where DSP effects such as bass management and DSP surround are bypassed. Can anything in terms of a volume control be done with any of these inputs or outputs?
If you're adept at soldering and can nut/bolt and follow instructions, then you won't have any issue with Jan Diddens's modification to the DCX2496. He's a talented engineer and that particular modification is superior to most I've seen. It's certainly better than some hack job I've seen advertised by various other members of this forum. Stay clear of those guys.
The DEQX is something completely different. You're aware of that, correct?
Dave.
Thank for the info, and yes I am aware of the difference with the DEQX and would prefer that hands down, but presently cannot afford three plus grand for a DSP. It is on my wish list though. One came up recently but I was outbid on it on Audiogon. Maybe next time. I have been thinking about Ashton's version of the mods. I know about Jan Gidden and the brilliant work he has done. Satie thought Ashton's mods would be a good choice...how about you? Have you looked at them?
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