Carver PT-2400 Dual Mono Vintage Amplifier Review

[Gorgonzola]

I bet the list of shortcomings for early solid state gear was far shorter than early tube gear. Tube fans obviously like the "Tube" sound, which is fine. This isn't however, indicative of a superior topology.

You're right that preference for tubes doesn't indicate superior technology. BUT tubes produced lots of 2nd/3rd order distortion that was less disagreeable than a relative preponderance of higher order harmonics. Ironically tube amps often have lot of high order harmonics but these are outweighed or masked by the 2nd/3rd harmonics.

S/S technology has advanced greatly since the '70s. In audiophile terms S/S was hindered by the myth that negative feedback is a BAD thing.. This idea was propounded by the likes of Nelson Pass and others. The reasoning was that substantial negative feedback produced higher order harmonic. This is TRUE, but sufficient negative feedback reduced ALL forms of distortion including high order ... that is, the solution to the problem of using little feedback is using a lot of negative feedback. Today's S/S amps have huge negative feedback and ultra-low distortion.

In my observation some tube fans, (not all), are moving away from that technology, finally realizing their original reason for preferring tubes has gone away.

 

[gabo4au]

Saw this review and some of the comments and had to go to my shop and take a picture of this.

I purchased this one new back in the day. Not exactly sure what year it was. Used it for many years until I replaced it with two Adcom GFA-565 Mono blocks, which I also still have!

This Carver still works, although I'm not using it at the moment. A few years ago I replaced a few caps in it. Sure it's not state of the art by todays standards and I have a bunch of amps that are better. But it's still good enough for a party once in a while.

Just FYI, the Adcom 565's... Those suffered badly from leaky caps. There was a guy a few years ago selling new input circuit boards, which were the ones that had the problems, and you could still buy all the parts for the boards. So I purchased a couple of those and rebuilt both boards. I now have pretty much a pristine pair of GFA-565's. And I rarely use those either! haha.

The amps I use most of the time are a Buckeye amp, along with powered speakers which have hypex fusion amps in them, a pair of Wiim Ultra amps, and an old Tube amp that I designed and built myself. I also have a few other amps around, Hafler DH-200 that I built in the 80s, a Bryston amp, several receivers Yamaha, Onkyo, Marantz, several TPA 3255 amps I've built, a few other solid state amps. Can't honestly remember all of them at this senior moment. But I have had an affection for amps since I was a kid and it continues to this day.

 

[davidc]

It is terrible by today's standards though probably not much worse than s/s amps of the '70s -- audiophiles abandoned s/s in the '80s and '90s in droves because they hated the sound.

My own s/s story is the Phase Linear 400. I bought mine about 1978 I kept the damned thing for more than 20 years not knowing any better. I even had it partially restored about 2000 which produced no improvement. If you ever trust anecdotal evidence, believe this: it sounded like shiite -- at once shrill and opaque. My next amp was a NAD C270 which was, at least, a big improvement. Subsequently I owned several s/s amps including a Pass Labs X150.5 which was a nice amp but not the equal of my current Purifi 1ET400A amp.

The common bias around here --instantly proclaimed -- is that "all amps sound the same" when operating within their parameters and volume-matched. By all means listen to their arguments but 55+ years of audiophile experience has proven to me personally that they don't.

I'm not knocking measurements. Look for ultra-low distortion whether class D or A/B. Such amps will be audibly superior to the likes of this Carver

While I don't doubt your experience with your Phase Linear 400, keep in mind it shares nothing with the Pt-2400 other than Bob Carver's name. They are completely different designs and are almost 20 yrs apart.

 

[davidc]

-- audiophiles abandoned s/s in the '80s and '90s in droves because they hated the sound.

Wait...what?

 

[Gorgonzola]

Wait...what?

Yes, my friend, it's true that many audiophile when back to tube amplification in the late '80s and early '90s in particular and it was because they found s/s amps "sterile", "harsh", "unmusical", and similar adjectives. How do I know? Because I lived through that era.

The argument for tubes lives on though it is beginning to decline. Check out a hard-core, high-end audiophile site such as 'Audioshark' if you doubt me. People there have a lot of ludicrously expensive equipment and pretty high proportion are adhering to their tube equipment. In particular check out the thread, "What type of amps do you use? Tube? Solid State? Both? Hybrid?". 40% are still using tube or tube-s/s hybrid equipment.

​

 

[Cogito]

"People there have a lot of ludicrously expensive equipment "

Which means absolutely nothing in terms of performance.

 

[davidc]

Yes, my friend, it's true that many audiophile when back to tube amplification in the late '80s and early '90s in particular and it was because they found s/s amps "sterile", "harsh", "unmusical", and similar adjectives. How do I know? Because I lived through that era.

The argument for tubes lives on though it is beginning to decline. Check out a hard-core, high-end audiophile site such as 'Audioshark' if you doubt me. People there have a lot of ludicrously expensive equipment and pretty high proportion are adhering to their tube equipment. In particular check out the thread, "What type of amps do you use? Tube? Solid State? Both? Hybrid?". 40% are still using tube or tube-s/s hybrid equipment.

​

I've lived through the whole era as well and I would sort of beg to differ for you. I would say the opposite in wording is correct. Meaning through the '70s '80s and '90s people left tube equipment in droves and went to solid state equipment.. there was always a subgroup of people who preferred tubes, and that subgroup may have grown in the 1990s, but I definitely would not say that people left solid state equipment in droves. I'd be happy to look up statistical sales data for you, but I doubt it's that important

 

[Gorgonzola]

I've lived through the whole era as well and I would sort of beg to differ for you. I would say the opposite in wording is correct. Meaning through the '70s '80s and '90s people left tube equipment in droves and went to solid state equipment.. there was always a subgroup of people who preferred tubes, and that subgroup may have grown in the 1990s, but I definitely would not say that people left solid state equipment in droves. I'd be happy to look up statistical sales data for you, but I doubt it's that important

Perhaps we'll have to end up disagreeing, but why not ask ChatGPT ...

Is there any evidence that many audiophiles returned to tube amplification from solid state in approx. the 1980s?

Perhaps you'll get a different answer but here's what 'Chat' responded to me (in part) ...

Yes. There is good evidence that a substantial segment of the audiophile community rediscovered vacuum-tube amplifiers during the late 1970s and especially the 1980s. It was not a mass-market movement—solid-state overwhelmingly dominated consumer electronics—but within high-end audio it was a genuine and influential revival.
...
How extensive was the revival?

There is no precise statistic for the share of audiophiles who switched back to tubes, but the evidence is strong:

• High-end magazines devoted increasing coverage to tube equipment.
• New companies built successful businesses around tube electronics.
• Vintage tube gear appreciated dramatically in value.
• Audio shows regularly featured tube amplifiers.
• The perception that "tubes sound more musical" became one of the defining themes of high-end audio in the 1980s.

 

[gentlejax]

considering what always happens in this forum when amps are tested I am really surprised someone sent in a PRO Carver and not one of the more popular M1.0t amps. I had one that was modified to the max and I wish I had thought to send it here before I sold it. its not a real surprise the PRO amp didnt score well. it wasnt meant for hi-fi .

someone should send in a m500 or whatever it is with the meters. it is the sound quality amp they say. ive had a dozen of them Carvers. but non right now.

 

[davidc]

considering what always happens in this forum when amps are tested I am really surprised someone sent in a PRO Carver and not one of the more popular M1.0t amps. I had one that was modified to the max and I wish I had thought to send it here before I sold it. its not a real surprise the PRO amp didnt score well. it wasnt meant for hi-fi .

someone should send in a m500 or whatever it is with the meters. it is the sound quality amp they say. ive had a dozen of them Carvers. but non right now.

You should read the link I left that the PT-2400 is essentially identical to the holy grail. TFM-75

 

[davidc]

Perhaps we'll have to end up disagreeing, but why not ask ChatGPT ...

Is there any evidence that many audiophiles returned to tube amplification from solid state in approx. the 1980s?

Perhaps you'll get a different answer but here's what 'Chat' responded to me (in part) ...

Yes. There is good evidence that a substantial segment of the audiophile community rediscovered vacuum-tube amplifiers during the late 1970s and especially the 1980s. It was not a mass-market movement—solid-state overwhelmingly dominated consumer electronics—but within high-end audio it was a genuine and influential revival.
...
How extensive was the revival?

There is no precise statistic for the share of audiophiles who switched back to tubes, but the evidence is strong:

• High-end magazines devoted increasing coverage to tube equipment.
• New companies built successful businesses around tube electronics.
• Vintage tube gear appreciated dramatically in value.
• Audio shows regularly featured tube amplifiers.
• The perception that "tubes sound more musical" became one of the defining themes of high-end audio in the 1980s.

You need to learn that the way you ask a question of AI will highly influence the answer. If you ask a question that seems like you are "trying" to get a certain response, that it the response you will get. Please read Amirs thread on AI questions.

Master AI (Artificial Intelligence) Discussion/News Thread

I don't need to tell you that AI is upon us big time. It is important that we all keep up with its developments, issues, etc. Instead of having multiple threads on it, I thought I create this single one so that people who are not interested, can just ignore it. And others know where to find...

www.audiosciencereview.com

 

[davidc]

You need to learn that the way you ask a question of AI will highly influence the answer. If you ask a question that seems like you are "trying" to get a certain response, that it the response you will get. Please read Amirs thread on AI questions. For example, in your reply, what the heck does "substantial" mean.?

Master AI (Artificial Intelligence) Discussion/News Thread

I don't need to tell you that AI is upon us big time. It is important that we all keep up with its developments, issues, etc. Instead of having multiple threads on it, I thought I create this single one so that people who are not interested, can just ignore it. And others know where to find...

www.audiosciencereview.com

 

[amirm]

Perhaps we'll have to end up disagreeing, but why not ask ChatGPT ...

Is there any evidence that many audiophiles returned to tube amplification from solid state in approx. the 1980s?

Perhaps you'll get a different answer but here's what 'Chat' responded to me (in part) ...

Yes. There is good evidence that a substantial segment of the audiophile community rediscovered vacuum-tube amplifiers during the late 1970s and especially the 1980s. It was not a mass-market movement—solid-state overwhelmingly dominated consumer electronics—but within high-end audio it was a genuine and influential revival.
...
How extensive was the revival?

There is no precise statistic for the share of audiophiles who switched back to tubes, but the evidence is strong:

• High-end magazines devoted increasing coverage to tube equipment.
• New companies built successful businesses around tube electronics.
• Vintage tube gear appreciated dramatically in value.
• Audio shows regularly featured tube amplifiers.
• The perception that "tubes sound more musical" became one of the defining themes of high-end audio in the 1980s.

That doesn't say that majority of high-end audiophiles went to tubes. Having co-owned one of those forums, I would say tubes were 20 to 30%, not all majority. That was still a high number but not majority.

 

[beefkabob]

Anybody got an a-500x to drop off with Amir?

 

[Mart68]

People there have a lot of ludicrously expensive equipment

That alone should tell you something. I agree some enthusiasts went back to tubes, in the UK that really happened in the '90s not before. Mostly on the back of shameless promotion by the magazines. The sales pitch was that tube fans are more discerning about sound quality which, whilst a non-sequitur, does add to the group-think.

Also many went to tubes as a sticking plaster to cover up bad speaker choices - 'My system can sound harsh, would a tube amp help?' is a common thread title.

 

[Gorgonzola]

That doesn't say that majority of high-end audiophiles went to tubes. Having co-owned one of those forums, I would say tubes were 20 to 30%, not all majority. That was still a high number but not majority.

No dispute. I didn't say that the majority of audiophiles went back to tubes. I did say the they when back to tubes "in droves" -- sorry for the hyperbole. I personally wasn't in the "drove".

I got my first real hifi system circa 1971. The electronics were Dynaco kits which I assembled myself. I might have gone for tube versions but instead opted for solid state, (assuming they were as good or better), consisting of PAT-4 preamp, Stereo 80 power amp, and FM-5 tuner. I've owned three tube preamps but never a tube power amp nor was I ever tempted to try one. However I did own one horrible sounding s/s power amp of the '70s vintage, a Phase Linear 400.

By the way, I'm quite well aware that if you ask AI a stupid question you may get a stupid answer; I don't need a lecture from @davidc on that account. If he thinks I got a stupid answer from ChatGPT he is free to challenge it.

 

[Gorgonzola]

That alone should tell you something. I agree some enthusiasts went back to tubes, in the UK that really happened in the '90s not before. Mostly on the back of shameless promotion by the magazines. The sales pitch was that tube fans are more discerning about sound quality which, whilst a non-sequitur, does add to the group-think.

Also many went to tubes as a sticking plaster to cover up bad speaker choices - 'My system can sound harsh, would a tube amp help?' is a common thread title.

Indeed IMHO tube amps with their high 2nd/3rd distortions were chosen -- consciously or otherwise -- to mask defects of up & downstream components, including crappy recordings.

 

[gabo4au]

Indeed IMHO tube amps with their high 2nd/3rd distortions were chosen -- consciously or otherwise -- to mask defects of up & downstream components, including crappy recordings.

Interestingly.. I am a musician (drummer) and I have a lot of guitarist friends that are also "stereo gear guys." They are all into tube amps and vinyl.

As guitarists who are all very much "gear heads" they love their tube guitar amps. For good reason, in the world of guitars, tube amps give you that great tube distortion. Everything from a little "breakup" to a bit of "crunch" to a full blown metal distortion, and if you have your pedal board in front of it you can get more flavors and enhance things with delays, drive, reverb etc. etc. The guitar tube amp distortion is the "gold standard" for guitars, even many solid state guitar amps have a tube front end. But it's all about creating the right distortion! Even the slight little "breakup" that is almost required even on what is mostly a "clean" guitar sound would be incredibly high distortion for an audiophile stereo amp.

So my theory is that they get so used to that guitar amp distortion that their stereo tube amps and vinyl replicates some of that. Imparting a colored sound that to them sounds right because they have spent so much time with their instrument amps and environment.

Of course all of this is just conjecture on my part. I have no scientific data to support any of it. The other thing I do know is that most of them are darn near deaf from spending much of their life on live stages. Interestingly I started using musician ear plugs when I was just a kid learning to play. So now at my old age I do not suffer near the hearing loss that most of my friends have. Just to give you an idea, one day over a few beers we discussed how many live shows we had played... Everyone there had at least 5000 shows under their belt, some close to 8000!! Without hearing protection that'll take a toll on you.

 

[Gorgonzola]

Interestingly.. I am a musician (drummer) and I have a lot of guitarist friends that are also "stereo gear guys." They are all into tube amps and vinyl.

As guitarists who are all very much "gear heads" they love their tube guitar amps. For good reason, in the world of guitars, tube amps give you that great tube distortion. Everything from a little "breakup" to a bit of "crunch" to a full blown metal distortion, and if you have your pedal board in front of it you can get more flavors and enhance things with delays, drive, reverb etc. etc. The guitar tube amp distortion is the "gold standard" for guitars, even many solid state guitar amps have a tube front end. But it's all about creating the right distortion! Even the slight little "breakup" that is almost required even on what is mostly a "clean" guitar sound would be incredibly high distortion for an audiophile stereo amp.

So my theory is that they get so used to that guitar amp distortion that their stereo tube amps and vinyl replicates some of that. Imparting a colored sound that to them sounds right because they have spent so much time with their instrument amps and environment.

Of course all of this is just conjecture on my part. I have no scientific data to support any of it. The other thing I do know is that most of them are darn near deaf from spending much of their life on live stages. Interestingly I started using musician ear plugs when I was just a kid learning to play. So now at my old age I do not suffer near the hearing loss that most of my friends have. Just to give you an idea, one day over a few beers we discussed how many live shows we had played... Everyone there had at least 5000 shows under their belt, some close to 8000!! Without hearing protection that'll take a toll on you.

As I understand, tube amplifiers are "it" for guitar amps. That is, tube characteristics are good thing, contribute to music making. Of course, music playback/reproduction is another matter; it the latter case tube characteristics may be a bad thing.

 

[EL_PW]

Always drooled over Carver separates back in the day, which were way outside of anything I could afford (Technics receiver and cd player and Bose 301's... shudder). Gotta admit those power specs (750 W PER CHANNEL) are IMPRESSIVE(!). Frightening even. Would have set my 301's on fire. Thanks for the review.