Carver Raven 350 Review (Tube Amp)

[solderdude]

The original post was that a certain demographic would buy this amp because it has a rising HF response that matches their hearing loss.

That small particular rise is not in any relation to the considerable different drop in response caused by aging or abuse.

I know about the high output impedance, so if the speaker should have a falling impedance at high frequencies (wait for it...) it would correct the amp!
if it is a rising impedance, then it wouldn't. In either case, that was not the question.

When a speaker has a lower as well as higher impedance the amp will change it's output voltage but in the wrong direction. So an impedance hump will ensure the output voltage rises even higher which is exactly what is not desirable.
A lower impedance will result in a lower than desired/intended output voltage so also exactly what one does not want (in the light of signal fidelity).

 

[Ken Tajalli]

The sound differences will potentially be marginally detectable in a direct, rapid-switching comparison. But on it's own? Dubious.

Thank you.

 

[Ken Tajalli]

When a speaker has a lower as well as higher impedance the amp will change it's output voltage but in the wrong direction. So an impedance hump will ensure the output voltage rises even higher which is exactly what is not desirable.
A lower impedance will result in a lower than desired/intended output voltage so also exactly what one does not want (in the light of signal fidelity).

As an ex OTL amp user, I am well aware of that.
Impedance hump, won't change the output voltage that much, am I right?
An impedance dip does reduce the output voltage

 

[fpitas]

As an ex OTL amp user, I am well aware of that.
Impedance hump, won't change the output voltage that much, am I right?
An impedance dip does reduce the output voltage

It's just a voltage divider. formed by the amp output impedance and the speaker impedance.

 

[solderdude]

As an ex OTL amp user, I am well aware of that.
Impedance hump, won't change the output voltage that much, am I right?
An impedance dip does reduce the output voltage

For an amp with a low output R it won't
For an amp with a fixed (usually also frequency dependent) output Z it will depending on the actual load.
With this particular amp it is even worse than a fixed high output R because of the added current feedback on top of the overall (voltage) feedback.

 

[Ken Tajalli]

For an amp with a low output R it won't
For an amp with a fixed (usually also frequency dependent) output Z it will depending on the actual load.
With this particular amp it is even worse than a fixed high output R because of the added current feedback on top of the overall (voltage) feedback.

Now we are getting into "this amp has multiple flaws" territory.
Did you also miss the bit about Hitler being short?

 

[fpitas]

Now we are getting into "this amp has multiple flaws" territory.
Did you also miss the bit about Hitler being short?

This being the internet, there are traditional ways to approach that. "You know who else had multiple flaws?" is a time-honored one.

 

[Ken Tajalli]

This being the internet, there are traditional ways to approach that. "You know who else had multiple flaws?" is a time-honored one.

Thank you, but there maybe Nazi's about.

 

[solderdude]

Now we are getting into "this amp has multiple flaws" territory.

It does so it already was in that territory.
You only mentioned something and responded to it.
There was no mentioning of Hitler nor anyone else in the part I quoted.

 

[Ken Tajalli]

It does so it already was in that territory.
You only mentioned something and responded to it.
There was no mentioning of Hitler nor anyone else in the part I quoted.

With respect, be good.

 

[Loomynarty]

I see!
And that @solderdude and @Blumlein 88 have liked it, interesting.
So here is a question to everyone:
- the worst case scenario (on the worst channel) is a slow rise to 0.6dB at 10kHz to about 1.2dB at 18kHz. Regardless of other failings of this amp, what demographic can even detect such a HF rise? Or benefit from it, to the point of buying it? (that was the point, if I recall)
I still say a demographic with very very good hearing! don't believe me? dial a 1.2dB parametric equaliser setting at 18Khz (Q possibly 0.2), and test it for yourself.
I am not saying it is beyond audibility! we are talking demographic of people with good or poor hearing.

This amp has multiple serious flaws! this minor, zoomed in FR discrepancy is neither here nor there.
It's like having a go at Hitler, because he was short!

Much like @solderdude stated, this FR discrepancy will only be enhanced by a speaker load, not reduced. The HF difference will likely be a few dB more than what the 4 ohm resistive load is causing. HF hearing loss is different for most people but, let's look at 12 khz as an example; we can see that with a 4 ohm resistive load the peak to peak difference is about 0.8 dB. Assuming we're using a speaker load, this difference will likely be around 1 dB or greater. 12-15 khz is a very sensitive area of our hearing as equal-loudness contours would suggest - if you've tested your own hearing you likely know there is a region above 10 khz which is more sensitive than above or below. Any increase in SPL in this region would cause the amp to sound brighter than an amp with flat FR regardless of hearing ability. In the case of someone who is just starting to experience HF hearing loss, this would more than likely cause the amp to sound closer to neutral as opposed to rolled off.

Alas, this is all moot if you're suggesting that the demographic which buys these amps have untrained ears.

 

[Postlan]

Higher order harmonic distortion is way too high for "subjectively" good sounding tube amp.

 

[PresbyByrd]

I go out of my way to be charitable, but this is a $5,000 paperweight.

 

[Ashoka]

Wasteful product: what is the amount of watts/h it requires to generate such a copious distortion? Like many other myths, it banks on the idea that the past was better than the present, and we deviated from some golden era when we went “solid state”. I own a pair of Dynaco ST-35 (one original, one clone): the enjoyment of Music is superior with my old Krell 300i, and light years ahead with any of the Hypex class D amplifiers. A complex Symphony like Mahler’s Third does benefit from the low noise and low distortion of modern amp design and their higher dynamic range.

confusing!!!! do you mean to say Dynaco is good? or Krell is better or Hypex is best?? (sorry, English is not my strength or I may not high in grey matters)

 

[AndreaT]

confusing!!!! do you mean to say Dynaco is good? or Krell is better or Hypex is best?? (sorry, English is not my strength or I may not high in grey matters)

Ok, Dynaco was one of the first stepping stone at a time in my life when most of my peers were listening to 45 rpm with a piezo needle and 0.5 W 5 cm diameter speakers. My very first sound system was the one in the picture, Christmas 1972. I began improving its sound with a 6 W mono kit amplifier from a company named GBC, now defunct. The Philips 2203 had a line output I put to use. Five years later I was gifted the Dynaco ST-35/PAS 3x from the living room: it landed in my bedroom driving a pair of AR 4x. Among many other stepping stones in the past half century, the Krell KAV-300i was a memorable upgrade, and the Hypex NC400 based mono blocks a very significant one. Yes, I enjoy very much my main present set-up to the point I do not think I will further try to improve it. I wished to point out that I have experienced tube sound, enjoyed it, and moved on.

 

[EL_PW]

I'm happy because the Carver bumped my Luxman Tub Amp up to third worst. Makin' progress!

 

[davidc]

Which cars are those?
there are plenty of cars with big engines that also have straight line performance. That isn't the same thing as not being good cars.

I think he's referring to all American muscle cars from the 60's and early 70's. When I got interested in those in my early teens, I remember my dad telling me that anyone can put a big powerful engine in a car, but my little TR6 will run circles around them on the track.

 

[Jimster480]

I think he's referring to all American muscle cars from the 60's and early 70's. When I got interested in those in my early teens, I remember my dad telling me that anyone can put a big powerful engine in a car, but my little TR6 will run circles around them on the track.

Yea it depends on what sells... Old school muscle cars weren't the fastest around the track. But the corvette was also fast and had a big engine.

 

[fpitas]

Why is there more power at 8 ohms than at 4 ohms?

At a guess, the output transformer gets less efficient the greater the transformation ratio from the anodes to the speaker.

 

[fpitas]

Indeed. Carver knows exactly what he's doing. He makes the Silver Seven <https://www.bobcarvercorp.com/silver-seven>. It would be hard not to be impressed by that forest of valves (tubes).

Omg. I wonder if you can go a day without a tube going bad.