Could it be I don't care for Class A

M

Mr Peabody

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Going back to my Pass X250, I enjoyed that amp and the sound, however, moved to Levinson liking the sharper leading edges and quicker response better.

There are characters of the Coda 8 that are better than my Levinson, more intelligible vocals and better detail in some aspects overall, it's just as fast, yet there is something I still likeabout listening to the Levinson better. The Coda has such a quiet background you'd have to hear it to believe.

I am mad at myself it takes me so long to figure these things out, now I am not able to return the 8. I'm going to try to get $5k back out of it, not even 120 days yet.

The real mystery to me is what is it I can't fully enjoy the 8, it's a great amp by anyone's standards. The 8 version I have is Class A for the first 12 watts, I'm wondering if I have an issue that I am one who may not prfer Class A. I don't like overly aggressive amps either. I guess we all have our sweet spot.

I also listen to a wide variety of music so amps that may excel on certain genres would present an issue for me.
 
For those of us old enough to remember, the original Mr. Peabody had something called a Wayback Machine for time travel. Pretty sure that could solve the problem. :)

Just having a little fun, I don’t mean to belittle your problem. I hope you’re able to find a good solution.
 
Having heard your Levinson/JBL set up I am somewhat familiar with that sonic presentation.
Reading your many post, it is clear that your taste runs more towards the accurate than the romantic.
I have found class A to offer a somewhat sweeter and more mid hall presentation. More similar to tubes.
And I can see where this Coda amp is a deviation from your preferred voicing.
I had a Coda amp a while back and sent it back to the factory to have the bias adjusted, making it a little more dynamic. It did help
but overall it was not a keeper in my system.
Hope you can get out of this without too much pain.
 
Gary, the Wayback would certainly fix things.

Joe, I probably didn't explain myself well enough. I knew the Pass was Class A up to a point, I was trying to show I moved on from the Pass to the 532h, some Class A to an amp with very little.

Dave,I suspect you nailed it. Liking a more accurate amp and keeping with one that won't offend leaves a narrow field. Or, high price tag, LOL
 
Ah, yes, sorry I misunderstood.

Sorry you aren’t crazy about the Coda.
 
joeinid said:
Even the Pass AB amps have some class A output. The X250.8 leaves class A at about 16 watts according to the spec sheets.


https://www.passlabs.com/wp-content/uploads/2019/12/Point8_specs_6.pdf
Click to expand...


Wow, that chart showing the 250.8 to leave Class A contradicts other reported spec's stating it runs in Class A for the first 25 wpc.

Mr. P., I have wrestled with do I want a very detailed system or one a little more rounded like my X250. It is a trade off for sure. On well recorded music, I like the extra detail but in the long run I find the Pass sound more listenable over a long period of time. I guess you can get a little extra detail with a DAC and/or preamp. The type of music player also plays a role. I use Audirvana or Hysolid for general listening and ease of use but for critical listening I go back to the the pain in the ass to use BugHead which sounds fabulous and detailed and is very tunable. As I have gotten older my tastes are for excellent tone and a romantic midrange vs extreme detail.

My son is dealing with the same issue. He recently bought a Cary SI-300.2d integrated which sounds fabulous by the way but at RMAF last year he heard the Primare Prisma I35 integrated which was hyper detailed and now wonders if he made a mistake.
 
I think I agree with you, although my experience of Class A amps stretches to just 2.

The Sugden Masterclass FPA-4 and Accuphase A-36. The former was a non-starter but the Accuphase is a wonderful amp that I kept for a couple of years before deciding that it was a little less involving or exciting than what I was looking for in an amp.

Amongst many A/B amps I've tried over the last couple of years, the new Mark Levinson 5805 was very civilised and nice sounding but I passed on that in the end. I found the GamuT D200 Mk III a better listen but sadly is was far too uncivilised in that it had no speaker protection relays so gave my 107dB speakers a most unwelcome thump on power up and down.
 
might not be helpful to your situation, but two thoughts that occurred to me:

sometimes my listening preferences/impressions are time and mood dependent... maybe give it a few weeks and switch the coda 8 back into your system and see if you still feel the same?

also, not to open up another rabbit hole but if you would like to keep the coda 8 for it's properties that you like then maybe a tube pre-amp would get you where you need to be in terms the overall sound having the right amount of politeness?
 
Mechnutt said:
Wow, that chart showing the 250.8 to leave Class A contradicts other reported spec's stating it runs in Class A for the first 25 wpc.

Mr. P., I have wrestled with do I want a very detailed system or one a little more rounded like my X250. It is a trade off for sure. On well recorded music, I like the extra detail but in the long run I find the Pass sound more listenable over a long period of time. I guess you can get a little extra detail with a DAC and/or preamp. The type of music player also plays a role. I use Audirvana or Hysolid for general listening and ease of use but for critical listening I go back to the the pain in the ass to use BugHead which sounds fabulous and detailed and is very tunable. As I have gotten older my tastes are for excellent tone and a romantic midrange vs extreme detail.

My son is dealing with the same issue. He recently bought a Cary SI-300.2d integrated which sounds fabulous by the way but at RMAF last year he heard the Primare Prisma I35 integrated which was hyper detailed and now wonders if he made a mistake.
Click to expand...

Hi, Mechnutt. I see this post is quite awhile ago but the issue or "detail" versus "round" has been quite relevant for me recently. Reading the objectivist hype over at Audio Science Review I decided to try Purifi 1ET400A-based amp. I also decided to sell my Pass Labs X150.5 having owned and enjoyed it for several years.

Well, the Purifi is a champion of resolution, transparency, and dynamics and the expense of being stone cold and highly intolerant of 2nd rate recordings. See my review at Audio Asylum ... REVIEW: VTV Amplifier Purifi 1ET400A Stereo Amplifier (SS) - Feanor - Amp/Preamp Asylum

My dilema today is whether I ought to retreat to a "rounder" sounding amp or take some other measure to mitigate the coldness of the Purifi. I have tried my Schiit Freya + preamp in Tube v. Passive Mode: this did "round" the presentation a bit plus offered tubes' "holographic" sound. However I quickly found myself missing the full transparency of the straight Purifi. So I'm still wondering what's to do?
 
Feanor said:
Well, the Purifi is a champion of resolution, transparency, and dynamics and the expense of being stone cold and highly intolerant of 2nd rate recordings. See my review at Audio Asylum ... REVIEW: VTV Amplifier Purifi 1ET400A Stereo Amplifier (SS) - Feanor - Amp/Preamp Asylum
Click to expand...

My amp (NAD M33) has the latest Purifi Eigentakt module but I wouldn't describe it as "stone cold". Granted it isn't warm like a valve amp, but neither is it cold. For me it offers a good balance with the feeling of the music being "live" rather more than most amps. You describe your amp as being Purifi 1ET400A-based . I thought 1ET400 was a Hypex module, but I'm not expert in these matters.
 
As Nelson has written about, I think some people prefer 3rd harmonic over 2nd harmonic distortion (ie. me).

For instance, I don't prefer SET amps - I owned a half dozen of them in my Zu days and this was re-confirmed to a lesser extent with a friend's SIT-3 recently.
 
I run Pass Labs X260.8s monos. They are Class A to 34 watts, then Class A/B. They are absolutely wonderful. If I ever decide upon my new system (COVID listening delays), it could easily include some Pass X600.8s - 100 watts of Class A, then Class A/B.

For me personally, this gives me the best of both worlds - excellent sound without too much heat. Most Class A amps run too hot for me here in FL, but Class A/B run warm, not hot.
 
it would take a person with an incredibly acute hearing ability to discern when an amp output stage slides from A to AB while playing program material (IMO its plain BS). I'm agnostic re class of operation, its the SQ that matters most when driving my particular speaker of choice. There are good and bad implementations of Class A design as all the other classes including D.
 
puroagave said:
it would take a person with an incredibly acute hearing ability to discern when an amp output stage slides from A to AB while playing program material (IMO its plain BS). I'm agnostic re class of operation, its the SQ that matters most when driving my particular speaker of choice. There are good and bad implementations of Class A design as all the other classes including D.
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I don't recall anyone stating they could hear the slide from Class A to B. However, having more Class A bias does effect the sound of the amp overall. As Pass states on their website, "Like all of the class A/B .8's, this amplifier has some class A bias, rewarding its listeners with a whole new zenith of sound quality."
 
Calvin said:
I run Pass Labs X260.8s monos. They are Class A to 34 watts, then Class A/B. They are absolutely wonderful. If I ever decide upon my new system (COVID listening delays), it could easily include some Pass X600.8s - 100 watts of Class A, then Class A/B.

For me personally, this gives me the best of both worlds - excellent sound without too much heat. Most Class A amps run too hot for me here in FL, but Class A/B run warm, not hot.
Click to expand...

The huge X350.8 ran just to the point of being uncomfortably warm in my LA-based living room. It is regularly 90+ degrees in the Valley summer here. YMMV.
 
KeithR said:
The huge X350.8 ran just to the point of being uncomfortably warm in my LA-based living room. It is regularly 90+ degrees in the Valley summer here. YMMV.
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I've never run a 350.8, but I've heard that the 250.8s run a little warmer than the 260.8s. Uncomfortably warm wouldn't be good for me either - Of course there's a lot of variables to consider such as room size, etc.

I was talked out of XA200.8s and XA160.8s (Class A) because they get HOT. According to a dealer the 600s about the same temp as the 260.8s. But the Boulder 2150s (Class A) run about the same as the Pass 260s (A/B).
 
Calvin said:
I've never run a 350.8, but I've heard that the 250.8s run a little warmer than the 260.8s.
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As an owner of the X260.8's I disagree. Two reasons, first the 260.8 is a mono amp, thus I have two of them and the 250.8 is a stereo amp. Secondly, the 260.8's have the highest amount of initial Class A bias(save the mighty 600) of any of the Pass A/B amps.

so therefore it's highly unlikely the 250 would run warmer.
 
Hear Here said:
My amp (NAD M33) has the latest Purifi Eigentakt module but I wouldn't describe it as "stone cold". Granted it isn't warm like a valve amp, but neither is it cold. For me it offers a good balance with the feeling of the music being "live" rather more than most amps. You describe your amp as being Purifi 1ET400A-based . I thought 1ET400 was a Hypex module, but I'm not expert in these matters.
Click to expand...

The 1ET400A is indeed Purifi, not Hypex; it's really just another name for the Eigentakt.

By the way, the NAD M33 is very impressive in its capabilities.

That Purifi module is usually coupled to some sort of input buffer that provide a some extra gain. The point is that this buffer can color the sound to some extent. The buffer usually include an op amp but might used a discrete circuit to provide this gain. My VTV amp uses a VTV buffer with at Sparkos SS3062 op amp, while NAD uses its own, proprietary buffer, so it's possible that my amp and your NAD could sound subtly different.

In any case, I misspoke describing the Purifi as "stone cold": the phrase has too negative a connotation. Rather I should simply have said it that it's not warm.
 
Mikado463 said:
As an owner of the X260.8's I disagree. Two reasons, first the 260.8 is a mono amp, thus I have two of them and the 250.8 is a stereo amp. Secondly, the 260.8's have the highest amount of initial Class A bias(save the mighty 600) of any of the Pass A/B amps.

so therefore it's highly unlikely the 250 would run warmer.
Click to expand...

Interesting. Again, my statement was based upon what I've heard by Pass users in the forums.

From what I understand with the monos you have a greater overall surface area to help dissipate the heat better. 250.8 (19 x 21.25 x 9) as compared to the 260.8s (19 x 21.25 x 7.5 - *** times two). Everything in the 250.8 is stuck into one box, so wouldn't it feel and run hotter?

There's only 9 Class A watts difference between the the 250.8 and 260.8. I'm not sure we could tell the heat difference from 9 watts. And the 600s, which have app. triple the Class A watts of the 260s allegedly run about the same temp as the 260.8s. But they also have a larger chassis (19 x 21.5 x 11 - *** times two).

A question: Would the Power Consumption of both amps make a difference in heat? 250.8 - 450 watts vs the 260.8 at 375 watts.

IMO, the smaller surface area of a 250.8 may make it feel and run warmer.
 
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