Carver Raven 350 Review (Tube Amp)

[pablolie]

Miatas are fine (especially the first generation MX-5, but I'll stick with BMW (not the new rubbish they're flogging, the old E-series stuff).

Not sure about the analogy. The Miata has always been a competent and fun car for its target audience. It has been successful because it was well-engineered for its goal. And it's pretty cool these days. I have never owned one, but I would not fault its engineering - its longevity shows the design considerations and product delivery were spot on and met a market need.

But if the original Miata had taken 14 seconds from 0-60, had been awful on twisty roads, and fell apart in rust within 3 years... it wouldn't be here still.

 

[Beershaun]

That is a ton of power coming out of a tube amp. Is that the most powerful tube amp that Amir has tested? I'm surprised it weighs only 43 lbs for as much power as it puts out and it's inherently low efficiency.

 

[GXAlan]

I agree - but clearly, why would they when their target market doesn't care and basically prefers the visual psychoacoustic effect of the glowing tubes (why doesn't anyone keep them really protected :-D)? Furthermore, tube supply is very limited, its manufacturing standards doubtful (especially with the Russian situation), and implementation know-how in industrial design a forgotten art... ? Just check the review results of every recent tube design tested in here....

I am in full agreement that modern tube amps (perhaps with exception of the Western Electric) have doubtful standards and the price point of the Western Electric is just for billionaires to show off functional art not for audio. You can buy Banksy that self destructs or a Western Electric tube amp that glows.

The vintage Dynaco beats the new one

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...

www.audiosciencereview.com

VTA ST-70 Review (Stereo Tube Amplifier)

This is a review and detailed measurements of the Bob Latino's take on Dyna ST-70 stereo tube amplifier. I believe (the kit?) costs US $1,430. This unit was bought used for around US $900. The polished stainless steal case looks very nice. The three transformers give it substantial weight...

www.audiosciencereview.com

The thing is, Dynaco was the budget option of its era. I believe that the very best tubes and tube systems are better. But they are still functional art and not about technical performance.

The point made about Russian tubes is well taken. I don’t know if tubes are still being made in Europe but the only Audio tube I know of in the US is Western Electric.

Exclusive: Western Electric confirms plans to tackle the tube crisis with its Georgia factory

The pro-audio brand tells Guitar.com how it plans to bring US-made guitar amp tubes back – and why it doesn’t want to charge a premium for doing so.

guitar.com

There is a whole world of military based vacuum tubes which do not apply to audio.

https://www.darpa.mil/news-events/2015-08-11

With some high power amps having a plate voltage upwards of 600v, you can add electrocution hazard to the mix.

Some of those old boxes scare this non-expert.

100%. The scary part is actually the newer stuff in my opinion!

 

[Steve Dallas]

Not sure about the analogy. The Miata has always been a competent and fun car for its target audience. It has been successful because it was well-engineered for its goal. And it's pretty cool these days. I have never owned one, but I would not fault its engineering - its longevity shows the design considerations and product delivery were spot on and met a market need.

But if the original Miata had taken 14 seconds from 0-60, had been awful on twisty roads, and fell apart in rust within 3 years... it wouldn't be here still.

Sort of to your point... The reason I keep the Miata is I need a backup car for the E46. The Miata requires almost no maintenance, whereas I have replaced absolutely every part of the E46 at least once; it is frequently unable to handle a track weekend. The Miata is always ready to go and always finishes. The E46 is faster, but the Miata is RELIABLE and fun.

(The RX-8 is a whole other can of worms.)

Normally, I would feel bad about taking a thread so far off track, but this amp is only a barely competent example of a tube amp, so I figure why not?

 

[Steve Dallas]

I am in full agreement that modern tube amps (perhaps with exception of the Western Electric) have doubtful standards and the price point of the Western Electric is just for billionaires to show off functional art not for audio. You can buy Banksy that self destructs or a Western Electric tube amp that glows.

The vintage Dynaco beats the new one

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...

www.audiosciencereview.com

VTA ST-70 Review (Stereo Tube Amplifier)

This is a review and detailed measurements of the Bob Latino's take on Dyna ST-70 stereo tube amplifier. I believe (the kit?) costs US $1,430. This unit was bought used for around US $900. The polished stainless steal case looks very nice. The three transformers give it substantial weight...

www.audiosciencereview.com

The thing is, Dynaco was the budget option of its era. I believe that the very best tubes and tube systems are better. But they are still functional art and not about technical performance.

The point made about Russian tubes is well taken. I don’t know if tubes are still being made in Europe but the only Audio tube I know of in the US is Western Electric.

Exclusive: Western Electric confirms plans to tackle the tube crisis with its Georgia factory

The pro-audio brand tells Guitar.com how it plans to bring US-made guitar amp tubes back – and why it doesn’t want to charge a premium for doing so.

guitar.com

There is a whole world of military based vacuum tubes which do not apply to audio.

https://www.darpa.mil/news-events/2015-08-11

100%. The scary part is actually the newer stuff in my opinion!

JJ tubes are made in Slovakia in relatively small quantities. China also still manufactures tubes. Russian tubes are currently embargoed due to retaliation against Western sanctions on Russia, and no more will be exported from Russia in 2022 according to the owner of New Sensor. The situation beyond 2022 is unknown at this time.

 

[Garrincha]

Let's not go overboard with these statements. Here is a published ABX test showing differences between amplifiers: https://www.audiosciencereview.com/...ts-did-show-amplifiers-to-sound-different.23/

I haven't read the article, but the short summary you gave at the linked thread. So didn't you answer there yourself that the perceived difference was because of clipping? This leads to the conclusion that it 1) was not audible distortion that was responsible and, more importantly, 2) that one of the fundamental criteria, to be driven without being overloaded, was violated.

 

[phoenixdogfan]

I'm sure your correct and it's meant to be this way... but why would one want a baked in sonic character that can never be altered?

If people are looking to play with distortion and noise levels, give this a whirl;

SPL TwinTube

Tube Tone and Warmth in an easy, smooth way. Make your bass drums, guitars and vocals stick out.

www.plugin-alliance.com

Much cheaper than this amp... or even a free one;

Tube Preamp

This plugin is now distributed by DDMF. It can be downloaded for free at: The following work is the result of my bachelor thesis, titeled “Real-time implementation of a tube preamplifier in o…

philaudio.wordpress.com

JSmith

I actually have both of those. I experimented with them a few years back. After listening for about half an hour, I disengaged the plug ins. Just obviously inferior to plain vanilla SS amplification to my ears.

 

[dougi]

JJ tubes are made in Slovakia in relatively small quantities. China also still manufactures tubes. Russian tubes are currently embargoed due to retaliation against Western sanctions on Russia, and no more will be exported from Russia in 2022 according to the owner of New Sensor. The situation beyond 2022 is unknown at this time.

There is a thread on tube availability for current discussions on this. The electro harmonix guy recently said a big shipment from Russia to the US recently happened.

 

[B&WTube]

The vintage Dynaco beats the new one

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...

www.audiosciencereview.com

VTA ST-70 Review (Stereo Tube Amplifier)

This is a review and detailed measurements of the Bob Latino's take on Dyna ST-70 stereo tube amplifier. I believe (the kit?) costs US $1,430. This unit was bought used for around US $900. The polished stainless steal case looks very nice. The three transformers give it substantial weight...

www.audiosciencereview.com

This is exactly where this forum has issues. Everyone who has heard both or upgraded their ST to VTA knows the VTA sounds better. Its much faster, cleaner, and has better bass response. However, on the measurements it fails. There has got to be some sort of pulling the subjective side more heavily into this, with blind A/B work.

I am not saying the data is wrong, but there is clearly much more to the picture. The VTA amp sounds significantly better than many of these amps that rank higher on the list. IMO, there needs to be some effort in distinguishing what are (and why) the subjective elements people prefer.

 

[DonR]

This is exactly where this forum has issues. Everyone who has heard both or upgraded their ST to VTA knows the VTA sounds better. Its much faster, cleaner, and has better bass response. However, on the measurements it fails. There has got to be some sort of pulling the subjective side more heavily into this, with blind A/B work.

I am not saying the data is wrong, but there is clearly much more to the picture. The VTA amp sounds significantly better than many of these amps that rank higher on the list. IMO, there needs to be some effort in distinguishing what are (and why) the subjective elements people prefer.

It is hardly surprising that people who have invested the money and effort to have the upgrade have decided that it sounds better. The word "faster" has no meaning other than slew rate or damping factor, both of which can be measured.

 

[USER]

I bet if you listened to some early Sonic Youth on vinyl with a Manly Chinook Phono stage it would just sound like TV static.

What on earth would make you say that? It's a well-made phono preamplifier made by people that know how to use tubes. Specs are available for it. They even provide more detailed specs when asked. Given equal loading, my Chinook sounds more or less like my Cambridge Audio Duo (90dB SINAD) and my Wayne Kirkwood Flat MM Preamplifier, which is to be expected if the low threshold for vinyl is passed. The robust loading options of the Chinook make it a great phono stage. Whether it is worth the premium price is another thing altogether.

Here are some quick measurements I made a while ago. (Denon DP-35F, Shure V15 V-MR, 45dB gain.) They aren't perfect measurements but clearly nothing is broken in the Chinook.


Chinook

Parks Puffin

 

[dougi]

JJ tubes are made in Slovakia in relatively small quantities. China also still manufactures tubes. Russian tubes are currently embargoed due to retaliation against Western sanctions on Russia, and no more will be exported from Russia in 2022 according to the owner of New Sensor. The situation beyond 2022 is unknown at this time.

There is a thread on tube availability for current discussions on this. The electro harmonix guy recently said a big shipment from Russia to the US recently happened.

 

[Cars-N-Cans]

I haven't read the article, but the short summary you gave at the linked thread. So didn't you answer there yourself that the perceived difference was because of clipping? This leads to the conclusion that it 1) was not audible distortion that was responsible and, more importantly, 2) that one of the fundamental criteria, to be driven without being overloaded, was violated.

I suspect this one is probably sitting on the edge of being audible, esp. with the broad spray of harmonics it generates. One thing it does have going for it is a relatively flat distortion profile with a large amount of power on tap. But that's basically like covering up a cow patty with a manure spreader. Its just consistently bad across the board. The real problem with the amp in my opinion is its not flat across the audio spectrum. On top of that it has a high output impedance by comparison to solid state amps so the speakers can potentially drag the output around depending on how reactive they are. Those will be audible, and make this a pretty crummy amplifier. And it will just be down hill from there as the tubes wear which basically means its a floor ornament that occasionally plays music. If it weren't for those things, you probably could get away with using it, otherwise. But distortion is a hard thing to quantify in absolute terms since the music will be a constant variable. Still my general experience is once its below about 1% its not audible anymore under most circumstances, which is fortunate for speakers.

 

[GXAlan]

Let's not go overboard with these statements. Here is a published ABX test showing differences between amplifiers: https://www.audiosciencereview.com/...ts-did-show-amplifiers-to-sound-different.23/

Do you believe the soft clipping effect accounts for a tube sound in the past?

This is exactly where this forum has issues. Everyone who has heard both or upgraded their ST to VTA knows the VTA sounds better. Its much faster, cleaner, and has better bass response. However, on the measurements it fails. There has got to be some sort of pulling the subjective side more heavily into this, with blind A/B work.

I am not saying the data is wrong, but there is clearly much more to the picture. The VTA amp sounds significantly better than many of these amps that rank higher on the list. IMO, there needs to be some effort in distinguishing what are (and why) the subjective elements people prefer.

Was this your amp that was sent in? I am not a Mullard tube expert by any means. However I do know that it is one of the most counterfeited brands out there.

If you look at the original picture, it looks like a brown plastic base, the glass is the same size as the base, and there is a 6CA7 writing at the top of the tube.

The ones I can find with the 6CA7 writing on top have a smaller tube relative to the base (XF1)

https://www.digikey.com/en/products/detail/tubedepot/NOS-6CA7-MULLARD-XF1/10489700

While the ones with the straight glass to base and the 6CA7 writing on top have a much larger getter

EL34/6CA7, Mullard, XF2, Double O Getter, New Old Stock

EL34/6CA7, Mullard, XF2, Double O Getter, New Old Stock

www.rfparts.com

And the ones with less getter like the picture, glass the same size at the base, typically have the writing in the middle.

It’s very possible that VTA modifications sound better when identical tubes are used.

@JohnYang1997 : can topping build and sell a speaker load for hobbyists to test amplifiers?

 

[digicidal]

I think a pair of these would be wonderful... sitting on top of a rack of "boring" SS gear with much better sound. I can't really afford a ~$9K "art piece" at the moment... but when I can, these would definitely close to the top of the list.

 

[sofrep811]

What on earth would make you say that? It's a well-made phono preamplifier made by people that know how to use tubes. Specs are available for it. They even provide more detailed specs when asked. Given equal loading, my Chinook sounds more or less like my Cambridge Audio Duo (90dB SINAD) and my Wayne Kirkwood Flat MM Preamplifier, which is to be expected if the low threshold for vinyl is passed. The robust loading options of the Chinook make it a great phono stage. Whether it is worth the premium price is another thing altogether.

Here are some quick measurements I made a while ago. (Denon DP-35F, Shure V15 V-MR, 45dB gain.) They aren't perfect measurements but clearly nothing is broken in the Chinook.


Chinook
View attachment 225314

Parks Puffin

View attachment 225315

It was a joke and Manley was an expensive one with tubes that came to mind.

 

[dougi]

I bet if you listened to some early Sonic Youth on vinyl with a Manly Chinook Phono stage it would just sound like TV static.

I remember going to some music event way out of LA somewhere in '92 while visiting friends, to see Pavement, Sonic Youth and Mudhoney play. I had never heard much of any of them before at the time, but the sound system was mixed in a way that they all sounded like TV static. Sonic Youth I could understand, but it wasn't till much later I realised that Pavement were supposed to be tuneful. I also remember seeing a Tarantula on the road on the way in slow traffic. We have deadly spiders in Oz of course, but nothing as big as those.

 

[USER]

It was a joke and Manley was an expensive one with tubes that came to mind.

I appreciated the joke but I just wanted to make sure you weren't saying all tube designs are this horrific. As discussed in great length in the other Carver thread, tube amps were once created with high-fidelity in mind.

I'm looking at my Murray Street LP right now. I may just stream the album.

 

[audiotron]

Awesome review as usual. I feel bad for the member that bought it.

 

[phoenixdogfan]

Blimey. I wonder how the Line Magnetics compare with this brand.

Should be about the same. All these high power pentode tube amps were meant to be distortion generators so as to give them mellow character while being able to power most speaker loads. This is the classic kind of amp TAS reviewers (esp HP) went gaga over. The names roll off the tongue: VTL, CJ, Audio Research, Jadis, Line Magnetics, Mesa Boogie, Cary, Carver, Manley, and Convergent Audio Technology. Anything putting out over 200 WPC into 8 ohms and costing less than $10k was considered a bargain. I sincerely doubt even one of them could attain a SINAD over 60 which is something even my $160 Behringer A500 can handily surpass.

I made the plunge into tubes in the mid-late 80s in a smaller way, buying a CJ MV 50 to power my LS3/5as at the time. For a while I enjoyed it, but I began to notice it overlaid everything with a kind of honey like glaze while blurring details. In short, it made everything sound homogenized and sweeter than live which to me is the very definition of a colored component. I found my Hafler DH 200 was actually far more transparent. So eventually I traded in the CJ and haven't looked back since. Generally, I think, people who want their music to sound a certain way (and I literally mean all their music) might find a tube amp appealing. So if you're the kind of guy who wants Johnny Rotten to sound like Tony Bennett, Keith Richards to sound like Chet Atkins, Stravinsky to sound like Brahms, and Wendy O Williams to sound like Linda Ronstadt, then tubes may just be for you.