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Dare I start a new thread on Denefrips Preamps?

73.147.221.113
Posted on June 3, 2022 at 18:46:00
Brody
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 I think I will dare. Now that I have the Hyperion amp, I'm very curious about the Hades or Athena preamps. But they both have 0 gain, so I'm curious to konw how this affects impact and dynamics. Would enjoy hearing from anyone with experience with these preamps or any other unity gain designs,

Thanks,

 

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Hey, why not ?!? Attractive pre's for reasonable cost, posted on June 4, 2022 at 05:38:50
Feanor
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 I'd certainly like to hear impressions from anyone who has any of the three models. (All are fully balanced, unity gain.)

There are few online reviews. The 'flagship' Athena looks very impressive indeed for just over US$2K. See the 6Moons review linked below. Measurements are remarkable.



Dmitri Shostakovich

 

Unusual design in some respects, posted on June 4, 2022 at 07:51:18
E-Stat
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 And bucks the usual trend employing a fully discrete, low feedback class A output stage!

 

RE: Dare I start a new thread on Denefrips Preamps?, posted on June 4, 2022 at 10:50:57
Mike Mount
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 I am mighty impressed by the build(s), the case work, tidy chassis and how well the product appears to be supported. It is especially nice looking for the price points. Started following on You Tube, some really good content to look over. KUDOS to Denafrips!!!

 

RE: Dare I start a new thread on Denefrips Preamps?, posted on June 4, 2022 at 10:51:56
Utley1
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 And their largest amp I hope also...Intriguing set of products....and their Pontus Dac

 

I though 6Moons said all-class A, low negative feedback, posted on June 4, 2022 at 11:42:35
Feanor
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 I don't recall anything one way or the other about discrete gain stage. But however achieved, distortion is extremely low, (per Denafrips).


Dmitri Shostakovich

 

Not surprising you miss details..., posted on June 4, 2022 at 11:49:33
E-Stat
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 I don't recall anything one way or the other about discrete gain stage.


 

RE: Dare I start a new thread on Denefrips Preamps?, posted on June 4, 2022 at 14:25:48
Ozzy
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 The Athena is on my radar as well. Zero gain is exactly what I want.






Don't worry about avoiding temptation. As you grow older, it will avoid you.
- Winston Churchill

 

RE: Dare I start a new thread on Denefrips Preamps?, posted on June 4, 2022 at 14:33:31
Brody
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 Definitely looking at Hades or Athena. I think the zero gain will work in my system, especially paired with the Hyperion, and my streamer has pretty high voltage gain running balanced.

 

RE: Dare I start a new thread on Denefrips Preamps?, posted on June 4, 2022 at 14:48:47
AbeCollins
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 Looks like it has an excellent all-important stepped attenuator volume control [not a cheap chip based control] and what appears to be very good build quality. I wouldn't mind trying one myself but I'm enjoying my Benchmark LA4.

I saw a review on 6Moons that inmate Feanor posted and it looks like the Denafrips Athena compares favorably against the highly regarded Wyred 4 Sound STP SE II, but the Denafrips doesn't look like it was built in a garage. Sorry Wyred 4 Sound. You make outstanding gear but you can do better on the case work with some of your products.

I forgot which inmate here in the Asylum had the W4S preamp and upgraded to the Benchmark LA4 which he prefers.

My ONLY reservation with Denafrips would be service even though I owned one of their products. My limit with over seas purchases is right around a thousand bucks. Any more and I get nervous but that's just my personal comfort zone. If something breaks I wouldn't be happy about shipping expensive broken product several thousand miles away over seas and dealing with customs issues, insurance if lost or damaged, and other potential delays.

The Vinshine website claims to have a US service partner but there's no weblink to that partner, and a Google search shows ambiguous results. I can't find that service partner.

Utilitarian W4S Preamp on top of Attractive Denafrips



 

Indeed, so as you say ..., posted on June 4, 2022 at 16:27:18
Feanor
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 No integrated circuits in the gain stage.

I guess the trend you are referring to is the use of op amps.



Dmitri Shostakovich

 

RE: Dare I start a new thread on Denefrips Preamps?, posted on June 4, 2022 at 19:31:56
regismc@wispertel.net
 All of the Denafrips components are voiced in a manner that can be considered more musical than analytical. 1 o'clock warm, with excellent drive and channel separation. They commit to the musical message, the individual notes in a smooth and coherant manner. They have a flow, a gestalt, that is unhurried but purposeful. The entire product line offers substantial build quality and in todays market, represents excellent value. Is it the 'end sound' you r after, really depends on your satisfaction and contentment level. Their design and engineering ethos does seem unique and as a hobbiest, that in itself can be worth exploring. I believe the 6Moons ended with the comparison of the amps as mirroring a type of EL34 musical Bobby note. Having a couple tube amps, Prologue II, and a Mystere PA11, and having done lots of tube rolling, I guess I can see that. The sound profile is easy to live with thru any number of speakers I've tried. The only time I've noticed a lack of gain, is thru a turntable, running a low output mc, at minimal gain on the Eat GloPetite, and fixing such, is a simple bump in the phono pre's gain stage itself. Otherwise both the Hestia and Athena I own easily drive my Hyperion, the Mystere, and the amp out of my Yamaha A-S2000. The difference between the two, like most extended product lines, is simply 'more'. More detail, more separation, more soundstage, more precise imaging. Otherwise voicing is the same. Hestia is just more 'in the box'. Athena can run 3 sets of amp outs, which is pretty cool, though I'm only running two, as I run the rca out to my Yamaha and an older set of ADS 880's. My understanding is that all three sets of outputs can be run concurrently over long runs. Athena has four sets of balanced inputs and only a single rca. Same with all the preamps, only a single rca input. One of the four, bypasses the input selection controls and is a little 'cleaner', not by much, but you can hear it. I only turn on my phono preamp feeding the rca input when I play lp's, otherwise my understanding is you may get some interference. For me, it's been no big deal, and the Petite fed by a Bob's Sky, VPI Traveler, and a Dynavector 20xL is very good. Your mileage may vary. Athena seems very transparent to cable inputs and downstream amp changes. I've a pr. of ProAc 1sc and completely solid state, with Hyperion and Athena is totally livable, enjoyable. Dropping in the Mystere can be startling. How can such a small mini monitor do that? I do run a single Rel T9i. The solid state setup is so smooth and musical I have on occasion thought of giving up the tubes as the normal blah, blah, blah, ...-. but drop that amp, driven by some WE6CA7 and some nice 6sn7 on front, is why this hobby is so fun. If you haven't heard the intoxicating, liquid, sedeuction, well, keep at it. What else? I really like the footprint of the smaller units, I'm over 'big rigs'. Athena is big. I've bypassed it several times, going dac direct, but I love my vinyl still and keep coming back to the Athena. Unity gain are kinda odd devices though, they don't use much power, and because they aren't additive they are kinda boring, perhaps in a good way, that's up to you. I did hear someone say they, their woofers, wanted more grip, more attack and control, than Athena offered thru it's unity gain architecture. The remotes are good, but most of the buttons are useless. The display can be dimmed, and personally I love the relays 'clicks' as it all feels solid. There is no pass thru, bypass or any such, just the basics. I've not heard the Hades, nor the larger amps. I don't own a tube preamp currently, but that would also require balanced outputs to drive any of the Denafrips amps. My current dacs are SMSL VMV D2 w/Gustard U18 DDC & a Benchmark Dac3. No R2R experience. CD player is the Rotel Tribute. I've some Zu DW's, Elac DFR, hot rodded Daedalus, Castle Conway III, Kef ls50, & the ADS. They all play well with the Denafrips gear. Music has 'body' in a relaxed but authoritative way, voices are very good.
In direct comparison, running the D2 direct into my PA11, with some great 6CA7 tubes, into the 1SC ProAcs sounds more 'alive', that setup breathes air, creates a cloud of its own special magic, snappy inner resolutions, attacks & decay, very SET like, but that's on that on small mini monitors w/only 40wpc, so limitations exist & I still can't play vinyl, so Athena stays...

 

Gotta say W4S products are downright and inexcusably ..., posted on June 5, 2022 at 04:44:31
Feanor
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 ... FUGLY.


Dmitri Shostakovich

 

I must say it strikes me as an accomplishment ..., posted on June 5, 2022 at 08:11:34
Feanor
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 ... If Denafrips gets the low distortion they claim using limited feedback, and I don't think this is achieved simply by avoiding op amps.


Dmitri Shostakovich

 

Simple answer!, posted on June 5, 2022 at 08:31:48
E-Stat
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 Use inherently linear devices that don't require boatloads of *correction*!

Companies have been doing that for decades. ;)

 

"No R2R experience", posted on June 5, 2022 at 08:38:57
AbeCollins
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I have limited R2R DAC experience using the Devafrips Ares II. It was definitely smooth and somewhat warm but lost a good amount of detail, transient attack, and transparency. It was excellent with 'simple music' like vocals, smooth jazz, but sounded congested with anything 'complex' like most of my rock music. It would probably be the polar opposite of your Benchmark DAC but I'm just guessing.



 

RE: "No R2R experience", posted on June 5, 2022 at 10:26:41
regismc@wispertel.net
 Abe, yes, and climbing up the product line gets u a bit more 'till, on top, u have everything. That's what I found climbing up to a 50k stack of Naim gear years ago and that's still true. People say the Pontus II is the 'sweet spot', the point of most return on $$$ on the dacs. Probably true. Still seems a nice value, performance combination. Sorting thru and balancing a systems 'compromises' may be the hardest part. Athena would perhaps be the equivalent of your Benchmark preamp, giving you this but may take away that. The Denafrips line is 'sure footed' in a way that makes it hard to get wrong from a musical perspective. They don't make a 'bright', nor offensive, piece of gear. Hestia may not be the absolute 'last word' in staging, nor resolution in my great room, but works and fits nicely into a second, non critical, listening space. The Benchmark 3 dacs features and versatility kept me hooked for years, but the VMV D2 is better now. I wish it had preamp inputs as that's a big one, but that's it. Having I2S input, allowing an affordable DDC, which Denafrips also has, really opens up the soundstage. Upsampling thru Roon sounds great, as does MQA. (I know) Somebody here should try one of their DDC's w/your I2S dac, it can be a real eye opener as the performance gains are substantial, especially for the modest cost involved.

 

Easier said than done -nt, posted on June 5, 2022 at 10:50:14
Feanor
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 nt


Dmitri Shostakovich

 

That's what I've lived with for eight years, posted on June 5, 2022 at 12:20:34
E-Stat
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 Same .002 THD+N @ 1kHz (using zero feedback) per Stereophile review:



 

RE: "No R2R experience", posted on June 5, 2022 at 18:04:49
Mick Wolfe
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 Strange, my original Denafrips Ares shines in the areas you call out as missing or lacking in the Ares II sample you auditioned. Nor have I seen these deficiencies mentioned in any of the Ares II reviews I've watched or read. FWIW, I use mine with a CXC transport/Oyaide 510 coax. IOW, nothing outrageous.
Maybe you pulled a bad sample :(

 

The SP20 is really nice (at 4X the cost), posted on June 6, 2022 at 04:14:19
Feanor
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 To be sure, the SP20 adds a phono preamp, etc.

I'm not sure what Reina means, though, when he says, "The result is the SP20 ($9000), a fully balanced, pure class-A preamplifier that uses no overall loop negative feedback."

Is "no overall" feedback the same as Zero feedback?

Meanwhile the Athena claims THD+noise an order of magnitude lower than the SP20, i.e. 0.00012% vs. 0.002%. Per 6Moons they claim "Low", not zero, feedback. But I'll wait for Amir to the measurements to confirm the Denafrips' claims, (I might have a long wait).

Anyway, I don't suffer from 'feedbackphobia' to the extent you do.



Dmitri Shostakovich

 

RE: Dare I start a new thread on Denefrips Preamps?, posted on June 6, 2022 at 06:09:51
Ozzy
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 What would you say are the sonic differences between the Hestia and the Athena?

And just how dim will the display get? I wish you could defeat it completely, but I don't want an annoying glare when the room is darkened.


Don't worry about avoiding temptation. As you grow older, it will avoid you.
- Winston Churchill

 

RE: The SP20 is really nice (at 4X the cost), posted on June 6, 2022 at 06:17:01
E-Stat
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 (at 4X the cost)

Completely hand assembled in Minnesota vs automated assembly in China.

Is "no overall" feedback the same as Zero feedback?

Local, aka "degeneration" vs loop feedback between multiple stages. Explained by Nelson Pass

Anyway, I don't suffer from 'feedbackphobia' to the extent you do.

Avoidable with small signal circuits and useful in low values (15 db) with power amps for overall stability and lowered output Z.

 

RE: "No R2R experience", posted on June 6, 2022 at 07:33:14
AbeCollins
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 What did you get to replace your Ares DAC ?

I've compared a handful of DACs along with the Denafrips Ares II. I can understand the appeal [everybody raves about it] but it wasn't for me. These somewhat recent auditions are better to my ears:

- RME ADI-2 DAC FS
- PS Audio NuWave DSD DAC
- Ayre QB9-DSD
- Chord Qutest
- Topping D90

But as we know, it comes down to personal preference. No argument from me that the Ares II was smooth and warm - but it gave up detail and 'slam' and it got a bit congested with anything but 'simple music'.




 

RE: The SP20 is really nice (at 4X the cost), posted on June 6, 2022 at 08:16:27
AbeCollins
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 I use measured specs [from ASR, Stereophile, etc] mainly as a starting point to weed out obviously defective products. I don't suffer from op-amp or feedbackphobia but I do look at the overall design to see where the designer's head is, but in the end its the sound that counts most to me.

All three ARC "tube" preamps that I once owned suffered from solid-state-itis. To be expected I guess from what were essentially JFET solid-state preamps with a tube buffer bolted on the output. Additionally these all used $2.00 IC chip volume controls. You have to move into the large five figure price range before ARC gives you a better volume control. I'd much prefer a good ALPS pot or better yet, discrete resistor volume control. Many preamp manufacturers do too, including all of the 'high-end' established brands I listed below. As they say, the volume control makes or breaks the preamp.

If these ARC "tube" preamps sounded like tubes to me, I wouldn't be so critical of them. But they didn't. To me a REAL tube preamp doesn't just bolt a couple tube buffers onto the output stage as ARC does. BAT doesn't do this. CJ doesn't do this. Aesthetix doesn't do this. Manley doesn't do this. VTL doesn't do this. VAC doesn't do this. Cary doesn't do this. Etc. Again, you have to move into the large five figure price range before ARC gives you a REAL tube preamp with hopefully a better volume control. And I would hope that these five figure ARC tube preamps sound like tubes.



 

RE: Indeed, so as you say ..., posted on June 6, 2022 at 08:21:32
AbeCollins
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But lets not ignore the fact that those Burson "discrete" op-amps that some folks love all use huge amounts of negative feedback just like IC op-amps.



 

RE: The SP20 is really nice (at 4X the cost), posted on June 6, 2022 at 09:10:20
E-Stat
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 Most preamps have multiple stages with a unity gain output buffer being the final one. The objective is lowering output impedance and the 6H30 is well suited to that function. Different companies choose tube or SS for either gain or buffer.

VTL and PS Audio take the opposite approach of the SP20 by *bolting* a MOSFET buffer to the 12AX7 or 12AU7 based gain stage for the 7.5 or BHK Signature.

And I would hope that these five figure ARC tube preamps sound like tubes.

My goal is for components to sound neither *like* tubes nor SS.

 

RE: "No R2R experience", posted on June 6, 2022 at 09:42:35
Mick Wolfe
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 Abe... No, still have the original Ares. Also have an LM 502 in a second system. Actually pleased with both of these DACs. If I were to replace either, the current Denafrips Ares or Pontus would be topping the list. That said, my friend is quite excited about his RME, so I may have to investigate in that direction as well. Bottom line, there's a lot of reasonably priced DAC's out there to choose from. Just have to find the one that fits your ear and budget of course.

 

No active devices are inherently linear, posted on June 6, 2022 at 12:03:37
13th Duke of Wymbourne
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 the voltage-in to current-out transfer curves all deviate from a straight line in some way or another. But, if you can get the voltage gain you want with only small current pertubations then distortion can be low. This works for a preamp but not for a power amp!

 

Some don't require *correction* for low distortion results -nt, posted on June 6, 2022 at 12:37:04
E-Stat
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Well this is certainly true, posted on June 6, 2022 at 13:00:25
Feanor
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 Let's be aware that the Burson discrete op amps are designed, (in varying degrees depending on the model), to mimic tubes by causing highish amounts of 2nd & 3rd order distortion. For instance see this distortion spectrum for the Burson V3 (as reported by Sparkos labs, see link) ...

Contrast that with the result for the Sparkos SS3602 which happens to be what I prefer in my VTV Purifi amp with VTV buffer ...

I tried Burson V6 Vivids, (supposedly less tube-like), in the VTV but found detail and dynamics to be compromised vs. the Sparkso.

BTW, unlike E-Stat I'm not obsessed about the evils of feedback nor of op amps, (be they integrated or discrete). Old fashioned thinking, (see E-Stat & Morricab), holds that negative feedback is bad because it causes high-order distortion -- and so it does!!. But while small to moderate amounts of feedback cause high-order HD, lots of feedback reduce all orders of distortion, high as well as low.



Dmitri Shostakovich

 

RE: "No R2R experience", posted on June 6, 2022 at 17:16:58
AbeCollins
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If you like the Ares you might not like the RME. The RME is more on the transparent and detailed side with no warmth. On it's own I don't consider the RME to be bright but some might find it to be just that if compared against the Ares II.

 

See previous answer, posted on June 6, 2022 at 18:53:56
13th Duke of Wymbourne
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 FETs & tubes have square-law transconductance, BJTs are exponential - none are linear. In general, if you arrange things to allow the signal current excursion to be along only a small part of the transconductance curve that might be linear enough (i.e. very strong class A biasing). Or, add some degeneration (local feedback) - that will straighten things out.
Whenever audio designers say 'no feedback' they mean no global feedback around multiple gain stages. Any designer who eschews local degeneration for audiophile sensibilities is not really a designer! Except in the case of tubes - if you degenerated the circuit you would not be able to hear the differences in non-linearity between tube types so clearly. That is a win-win, poor circuit design* gets passed-off as voicing/tuneability and everyone is happy:)


*I am joking about poor design. If it is what customers want then it is the right thing to do.

 

In the end..., posted on June 6, 2022 at 19:12:06
E-Stat
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 the reproduction of music is what matters most. :)

 

We should all read Bruno Putzeys' "The F-word", posted on June 7, 2022 at 04:32:21
Feanor
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 I'm not technical enough to understand the mathematical nuances but I understand the gist of it: if a little feedback can be bad, a lot of it is great. Yes, I know, your device must have enough "open loop gain" to sustain a lot of feedback.

Follow the link below to find it ...



Dmitri Shostakovich

 

RE: "No R2R experience", posted on June 7, 2022 at 09:12:06
Mick Wolfe
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 Interesting you mention that. My friend with the RME DAC also has a Border Patrol DAC. I guess one could assume these two DAC's represent a wide gap in their sonic signatures. Yet he's able to enjoy both. In his words, the RME presents more detail for sure, yet its voiced in such a way that it's enjoyable and in no way fatiguing. He's also owned the Ares II along the way. To put simply, he says the Ares II falls somewhere in the middle of the two above DAC's in its presentation.

 

+1, posted on June 7, 2022 at 13:21:50
13th Duke of Wymbourne
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 Enjoyment/engagement are what I prize most and I'm not too worried if it means my system is coloring/supplementing the source. I suspect many feel that what they prefer must be objectively better too and that might not be the case. Audio is broad church that allows many philosophies and it is not like we're talking about aircraft landing radar where it either works or people die! So, some things in audio that don't work so well still have a place and our world would be duller without them.

 

RE: We should all read Bruno Putzeys' "The F-word", posted on June 7, 2022 at 14:07:01
13th Duke of Wymbourne
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 That is a good article but a bit esoteric. It is not applicable to our discussion here about the inherent linearity/non-linearity of active devices but it is about global feedback around a whole amplifier and how to add more. To keep stability, usually open-loop gain is rolled-off from a very low frequency so there is a lot of 'excess gain' at low frequencies to correct distortion but at higher frequencies less correction can be made. Mr Putzey presents a method to increase the gain at higher frequencies and still keep the closed loop system stable.
I believe the idea goes back to Bob Cordell for audio amplifiers but, I suspect, the concept itself is a lot older in the general field of system design and servo control.

 

RE: Dare I start a new thread on Denefrips Preamps?, posted on June 7, 2022 at 21:05:57
regismc@wispertel.net
 I wouldn't worry about the display, unless u r overtly anal, it's got three levels of brightness. It gets pretty dim, though I do have bad eyes...- Frankly both preamps, Hestia and Athena, could bore u to tears, but that seems to be my take on most modern preamps. Really they just disappear. I think I noted Hestia as more 'in the box', Athena has better channel separation. Someone not attuned may not even hear a difference as the tonal presentation is similar. Akin to adding a DDC thru a dacs I2S inputs, everything is a bit better spaced, more relaxed more hifi in a good way, a bit more focus and a touch more decay. It's 'better', but in a non critical environment, office or bedroom, you'd probably not fully appreciate the improvements. In the main room, yeah it's twice as good, you won't want to give up what Athena brings. She would be hard to replace. Neither does anything wrong tonally as both are rich and earthy, clothing musical messages with a flesh and bones body, a bit of soul & a bit of grit. These guys can rock the flow as I've heard some 90's grunge sound thrilling thru both, they don't sound lean or transistorly (is that a word?) nor too clean, nor sterile. They aren't lightening fast but they aren't slow nor overtly colored or phat like many older tube amps. Both are kinda minimalist machines, never drawing attention to themselves, never making a fuss. I wish both had an additional rca input as I dabble in cassettes also with an old Nak deck. Sound wise, I could live with Athena forever, function wise? Hestia is just so damn pretty, I gotta find her a home as I'm fond of her look and feel, the way she 'clicks' when I rotate her big aluminum dials. I once owned a beautiful Dodd battery tube preamp, a chromium blonde, bitchin' piece I had to sell clear cross the globe. Sometimes, breakups are hard and I'm just not ready...-

 

Accu Jack, posted on June 8, 2022 at 16:06:04
AbeCollins
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 Reminds me of what we jokingly called "accu jack" back in the engineering department in my early career. It was a pneumatic analog servo controlled throttle actuator for a car gas pedal. If the PID control wasn't set just right accu jack's shaft would cycle in and out rapidly and uncontrollably.




 

I'm drawn to Putzeys' conclusions at the end "The F-word", posted on June 9, 2022 at 04:34:33
Feanor
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 Unfortunately my lack of technical and math savvy means most of the article is mumbo-jumbo to me.

Putzeys's final conclusions, viz. that is essentially that there is no such thing as too much feedback, and that includes multi-stage feedback loops as well as local strike me as valid based my listening to my Purifi amp. ("Degenerative" is term I hadn't hear before reading this thread).

E-Stat got on about the supposed inherent linearity of amplifier components which you, Duke, addressed. However E-Stat's fundamental agenda is anti-feedback in general; this is misguided, IMHO, based on Putzeys and other commentators of the last couple of decades. E-Stat's archaic views on feedback are the basis for his categorical hatred of typical, integrated op amps which is, according, also misguided.


Dmitri Shostakovich

 

RE: I'm drawn to Putzeys' conclusions at the end "The F-word", posted on June 10, 2022 at 01:56:56
morricab
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Location: switzerland
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 My categorical hatred is based on hearing literally dozens of high feedback amps.

I have heard a number of Putzey's designs where of course he is putting his theories into practice. The sound? Not musical.

E-Stat is not misguided, no-feedback designs often (but not always) sound closer to real music. High feedback designs have yet to produce a single example I could point to where I say "yes, it can be done this way"

 

RE: Simple answer!, posted on June 10, 2022 at 01:59:38
morricab
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 Ah! you mean TRIODES!

 

RE: See previous answer, posted on June 10, 2022 at 02:01:19
morricab
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Posts: 9180
Location: switzerland
Joined: April 1, 2005
 According to Boyk and Sussmann, the triode actually follows a 3/2 law and not a quadratic law like FETs. This makes them somewhat more linear.

 

RE: The SP20 is really nice (at 4X the cost), posted on June 10, 2022 at 02:11:53
morricab
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Posts: 9180
Location: switzerland
Joined: April 1, 2005
 BAT makes a very good preamp. Aesthetix too. Not as big a fan of CJ or VAC pres.

Check these out though for something different:

https://aries-cerat.com/incito-product-page/
https://aries-cerat.com/incito-s-product-page/

Very low distortion, tube rectified, transformer coupled output triode preamps.

Incito has resistor ladder volume control Incito S has transformer volume control

 

We're entitled to our sound preferences, posted on June 10, 2022 at 04:23:09
Feanor
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Posts: 9872
Location: London, Ontario
Joined: June 17, 2003
Contributor
  Since: March 12, 2004
 Listening to audiophile preference for over 20 years I understand there are many who prefer the "musicality" of tube amps (and some S/S amps). Descriptions often include sound that's full, smoother, and (sometimes) having layered or "holographic" imaging. I have heard these qualities myself from certain equipment and understand what those folks are talking about. I agree that people are entitled to like these attributes.

Your explanation is that negative feedback robs the sound of these qualities because it causes higher order harmonic distortion.

My hypotheses is what what mainly contributes to these attributes isn't exclusively the absence of high order harmonics but, rather, the presence of 2nd and/or 3rd order harmonics.

I believe that lots of feedback reduces all harmonics and that includes high level harmonics. But it also greatly decreases 2nd & 3rd order harmonics and I believe that is why many do not like ultra-low distortion amps such as Purifi or Benchmark.


Dmitri Shostakovich

 

My preamp has tube amplification front to back, posted on June 11, 2022 at 05:20:30
Feanor
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Posts: 9872
Location: London, Ontario
Joined: June 17, 2003
Contributor
  Since: March 12, 2004
 That is Sonic Frontiers Line 1 SE+ which has no s/s stages. But, OPPS !!, it does have PGA2311 volume control chips that have op amps, and very robust S/S power supply.

It's very transparent and very neutral but not very tube-like. I'm sure morricab would hate it.






Dmitri Shostakovich

 

RE: We're entitled to our sound preferences, posted on July 18, 2022 at 01:21:03
morricab
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Posts: 9180
Location: switzerland
Joined: April 1, 2005
 Lots of feedback creates more and more harmonics, even if very low in level, that acts like an artificial noise floor, which is signal modulated...because it's not really noise.

 

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