Carver Raven 350 Review (Tube Amp)

[DanielT]

Thanks Amir! Interesting test, measurements. These tube amp tests are entertaining. Expensive as fu** and measure as they do. But that's what people buy tube amps for, I imagine. To get a colored sound. In this case, it is also probably paid extra for the Carver brand itself as well.

So cost of a monoblock is US $4,750. If two pieces are needed for stereo, double the price.

This was good you said Amir:
Unlike the 275 amplifier, the fuses did not blow and the amp survived my sweep tests
Always something.

Isn't a tube sitting crooked in the amplifier? That:

 

[xaviescacs]

As far as the THD goes… I think they were hoping Amir‘s equipment broke down. Trust and verify… more of the latter.

I mean, if they advertise less than 0.5%, which is a lot, they know it's audible, and knowing there are products that produce almost no distortion, they seem to agree that a bit of distortion is a nice thing. Hence, why not specifying it as something good instead of something to bad. Saying less than 0.5% as if it was a good thing to have this upper limit is a bit absurd, it would be better to just don't say anything about distortion, ignoring it as the amp does xD That, or presenting it as a good thing, and proudly announcing that this amp has up to 0.5% of good distortion.

 

[MediumRare]

I rated this #2 instead of #1, "broken". Clearly it is WYSIWYG and not broken. Prodigious amounts of power should result in healthy dynamics; the distortion levels are at the edge of audibility and buyers over 50 can’t hear much anyway (me included). I’d never even consider this let alone have it in my system at any price, but at least it’s not a $20,000 USB cable.

 

[Deleted member 50971]

I mean, if they advertise less than 0.5%, which is a lot, they know it's audible, and knowing there are products that produce almost no distortion, they seem to agree that a bit of distortion is a nice thing. Hence, why not specifying it as something good instead of something to bad. Saying less than 0.5% as if it was a good thing to have this upper limit is a bit absurd, it would be better to just don't say anything about distortion, ignoring it as the amp does xD That, or presenting it as a good thing, and proudly announcing that this amp has up to 0.5% of good distortion.

That’s a good question and I agree. My thoughts would be there are not very many tube amps, if any that measure as well as SS amps.

ASR influence? People/Manufacturers have (or need to) to acknowledge that pretty much every tube amp tested on here, doesn’t measure like it’s SS counterpart.

I think stating that it’s a full 1% THD would have knocked sales down. I hate to be cynical like that, and I really like to give people the benefit of the doubt especially when I don’t know them personally. But in this marketing driven world we’re in, I can’t think of another reasonable explanation. Faulty unit? Probably not.

I’ll let some of the more influential people answer on here, because these are just my thoughts.

 

[Lambda]

83.476dB with respect to 5W@4R is 270uV of noise, or 0.27mV.

thanks.
So with efficient speakers there is a good chance to hear some noise

 

[SIY]

Do you see any “longevity“ advantages with some NOS OEM’s?

Not so far. TBH, I tend to run tubes very conservatively so their lifetimes may exceed mine.

 

[Dmitri]

Always one for a good laugh, I have ASR next to Audiogon on my “favorites“ list on my IPad. After the Carver Crimson 275 review, I noted an uptick in Crimson‘s for sale. Perhaps the Carver Raven…(including this particular amp?) might suddenly start showing up on Audiogon? Evidence that ASR might just be making a difference in the uncovering audio BS?

One could only hope.

 

[DMill]

Hopefully Amir can get a hold of another brand of tube amps. It’s looking like Carver does not have any interest in measurements nor building amps with working taps and proper grounds. I’m hopeful for tube amp enthusiasts that somebody else is making better than this

 

[Garrincha]

Would anyone notice the fact that this has measurably poor performance in a DBT?

I doubt so. The distortion is about 50dB. It is very hard to hear anything as low, even just with sine tones, let alone music material, you can check for yourself: https://www.klippel.de/listeningtest/.

 

[DanielT]

I doubt so. The distortion is about 50dB. It is very hard to hear anything as low, even just with sine tones, let alone music material, you can check for yourself: https://www.klippel.de/listeningtest/.

But surely it also depends on what type of distortion it is? #134 in this thread:

As for distortion, as the fundamental gets louder, low order distortion products become less and less audible. Compression drivers have second order dominated HD profile. According to Geddes Lee's research, participants of the research couldn't hear even %20 distortion of compression drivers while they are playing loud.

Genelec S360 Review (Studio Monitor)

The review compares to the 8361a, but isn’t the 8351b the better comparison at the same price point? Which is the better speaker then?

audiosciencereview.com

 

[Garrincha]

But surely it also depends on what type of distortion it is? #134 in this thread:

As for distortion, as the fundamental gets louder, low order distortion products become less and less audible. Compression drivers have second order dominated HD profile. According to Geddes Lee's research, participants of the research couldn't hear even %20 distortion of compression drivers while they are playing loud.

Genelec S360 Review (Studio Monitor)

The review compares to the 8361a, but isn’t the 8351b the better comparison at the same price point? Which is the better speaker then?

audiosciencereview.com

True, but this reasearch only shows that many forms of distortion are even less audible. I did the Klippel Test and managed to hear abour 53dB on test tones, which is already much more than the average (maybe I got lucky). On music material it is much less audible. So in fact 1% distortion, which is 40db, should be quite save to be inaudible in music.

 

[DanielT]

Hopefully Amir can get a hold of another brand of tube amps. It’s looking like Carver does not have any interest in measurements nor building amps with working taps and proper grounds. I’m hopeful for tube amp enthusiasts that somebody else is making better than this

Buy a classic instead. If you want a tube amp. If the effect is sufficient:

Review and Measurements of Dynaco ST 70

This is a review and detailed measurements of the vintage Dynakit Dynaco Stereo 70. It is on kind loan from a member who bought it used online and repaired it. Previous owner hand upgraded it but could not get it working. Given that it is 60 years old, one can forgive the rust and dust...

audiosciencereview.com

With such old amplifiers, it is probably a prerequisite that you know electronics. Considering what Amir wrote in that review:

It is on kind loan from a member who bought it used online and repaired it. Previous owner hand upgraded it but could not get it working.

Used here:

Used Dynaco ST70 Stereo power amplifiers for Sale | HifiShark.com

Used Dynaco ST70 Stereo power amplifiers for sale on 400+ second hand hifi sites & shops. Use Hifi Shark to monitor pricing and global availability

www.hifishark.com

 

[DanielT]

True, but this reasearch only shows that many forms of distortion are even less audible. I did the Klippel Test and managed to hear abour 53dB on test tones, which is already much more than the average (maybe I got lucky). On music material it is much less audible. So in fact 1% distortion, which is 40db, should be quite save to be inaudible in music.

Not to mention how less sensitive we become to distortion in the lowest frequencies. At 50- 80 Hz, presumably, for many, around 20dB, 10% distortion is inaudible.

 

[xaviescacs]

True, but this reasearch only shows that many forms of distortion are even less audible. I did the Klippel Test and managed to hear abour 53dB on test tones, which is already much more than the average (maybe I got lucky). On music material it is much less audible. So in fact 1% distortion, which is 40db, should be quite save to be inaudible in music.

I think, if there is one tone at 1kHz, and other ones at higher frequencies, with less intensity, like what happens with music, with not notes at quite different intensities, the distortion of the 1 kHz tone will mostly mask the higher ones, or not? Perhaps isn't easy to "hear distortion", but I bet there is a loss of clarity. Just my thoughts.

Edit: typo.

 

[Steve Dallas]

I agree. It doesn't look like a lifting handle, which you would expect to be centred, and where's the matching one at the back? It also looks as if it might be attached only to the top plate, so could it even take the weight?

It is a guard rail to protect the more fragile preamp tubes. It has been done since at least the 1950s.

Those tubes didn't give better linearity than "consumer" grade ones. Many of the best measuring tubes I've tested over the years were from standard suppliers like JJ or Electroharmonix.

The whole NOS thing is a rationalization of baseball card collector mentality.

When I was in the guitar amp business from 2000 - 2010, I became quite a NOS tube collector. I recently sold that collection for over $15,000, which was a ~500% profit. The mystique around NOS tubes and tube rolling is alive and well. You should see the current price of new tubes, though!

I learned that JAN tubes tend to have reliably lower noise and microphonics. Otherwise, most tubes sound pretty much the same, although they have different distortion profiles (the much debated "hardness" measure) from tube to tube, model to model, and brand to brand.

At the time, I purchased power and preamp tubes by the case from New Sensor and another vendor I cannot recall at the moment. Among preamp tubes, I failed roughly 40% for noise and/or microphonics being too high. Quality control was terrible. New Sensor would not accept returns, as they claimed guitar amps are too harsh an environment for their products, and they are meant for home hi-fi, which was an obvious disingenuous dodge.

Among preamp tubes, I found the Sovtek 12AX7WA and WB had the best quality control, but customers wanted EH at a minimum, found JJ to be acceptable, and really wanted T-S. Some customers would actually get angry if I shipped them Sovtek tubes. So, I threw hundreds of tubes in the trash. Sure wish I still had those to sell to Hi-Fi tube rollers about now!

 

[tmtomh]

To each their own, but for crying out loud - why not just get an inexpensive pro amp and stream to it using an aural exciter plugin? Same result, 1/5th the cost.

 

[DanielT]

Among preamp tubes, I found the Sovtek 12AX7WA and WB had the best quality control, but customers wanted EH at a minimum, found JJ to be acceptable, and really wanted T-S. Some customers would actually get angry if I shipped them Sovtek tubes. So, I threw hundreds of tubes in the trash. Sure wish I still had those to sell to Hi-Fi tube rollers about now!

He also thinks so, 1:25 in the video.

That entire video is entertaining in and of itself:

Edit:
He in the video recommend Sovtek 12AX7LPS in and of itself. I don't know the difference between that tube and the one you mentioned Sovtek 12AX7WA, but it's the same brand anyway.

 

[theREALdotnet]

So cost of a monoblock is US $4,750. If two pieces are needed for stereo, double the price.

Well, they have a more budget friendly version.

 

[solderdude]

Why and A meter

It is for setting the bias of the tubes. Useful feature as tubes change specs over time and for tube-swappers.

 

[AudioSceptic]

I own a valve-amplifier from EAR. It must be a better designed valve-amp because I don't hear any nice warm fuzzy sound. No richness either. I only hear a folded relatively rumbling bass, less clear treble and generally a bit weak dynamics. And a tendency to mush the sound in intense and strong parts. Not that it sounds bad, but compared to my Purify class D it is kind of tired. But it cuts in a pleasant way. On the other hand my class D does not cut at all.

No surprise there. Tim de P was highly thought of. He designed for Luxman for a while, as well as making his own EAR amps.