Carver Raven 350 Review (Tube Amp)

[Sokel]

A tube amp is more likely to perform worse into a speaker load than a resistor load. A resistor is easy. A speaker is a messy soup of back EMF and non-flat impedance curves. The relatively high output impedance of tube amps don't like varying loads and would rather loaf a long all day just powering a resistor with this nice constant 8 ohms.

Tube amps always were more appropriate with highest sensitive speakers. In their heyday almost all speakers were like this.

If I didn't use the Klipsch speakers I have now, with their their high sensitivity, my tube amp would not be appropriate. I really think that very powerful tube amps are kind of silly because the type of speaker a very powerful amp would be used with are not the type of speaker that would work best with a tube amp. The Carver falls into this category.

I was always wondering about this paper that comes on and on for ages,about tube amps working in current drive with appropriate speakers as a system.
Is there any truth in that?
(genuine question,I know nothing of tube amps but it always comes as evidence by people who love them)

 

[BrokenEnglishGuy]

is not like these tube amps have the '' good '' 2nd harmonic distortion? something like that?

 

[solderdude]

In essence the paper describes that current drive gives lower distortion but requires either open loop compensation, special drivers (as in no impedance hump) or MFB for at least the bass. For 2-way and higher it requires separate amplifiers.

This rules out that tube amplifiers can have these benefits.
Afterall they are just voltage sources with a poorer output resistance than SS due to OPT and lack of open-loop gain and low feedback.

Tube amps as well as SS amps can be designed as current drive. This is topology dependent and not component dependent

 

[Sokel]

In essence the paper describes that current drive gives lower distortion but requires either open loop compensation, special drivers (as in no impedance hump) or MFB for at least the bass. For 2-way and higher it requires separate amplifiers.

This rules out that tube amplifiers can have these benefits.
Afterall they are just voltage sources with a poorer output resistance than SS due to OPT and lack of open-loop gain and low feedback.

Tube amps as well as SS amps can be designed as current drive. This is topology dependent and not component dependent

Apart from the research the interesting thing is that they talk about the benefits of DSP some 40 years ago.

 

[RammisFrammis]

I was always wondering about this paper that comes on and on for ages,about tube amps working in current drive with appropriate speakers as a system.
Is there any truth in that?
(genuine question,I know nothing of tube amps but it always comes as evidence by people who love them)

I don't have time to get into it more but suffice to say that tube amps work best with efficient speakers like my Klipsch La Scala where 40 watts is far more than enough. A high power tube amp is a waste of money in my opinion since a speaker which needs tons of power is NOT going to work best with a tube amp! If you have that then buy a good SS amp or class D. The audio marketeers have twisted themselves into pretzels in trying to sell high distortion tube amps to drive speakers they have no place being paired with. This gives tubes a bad name and people assume that ALL tube amps are like this Carver crap and produce tons of distortion. This is not what tubes are about and never have been.

 

[Sokel]

I don't have time to get into it more but suffice to say that tube amps work best with efficient speakers like my Klipsch La Scala where 40 watts is far more than enough. A high power tube amp is a waste of money in my opinion since a speaker which needs tons of power is NOT going to work best with a tube amp! If you have that then buy a good SS amp or class D.

I already have 3KW of amps,I think I'm ok

 

[RammisFrammis]

I already have 3KW of amps,I think I'm ok

Your application must not be typical HiFi listening. Nothing to see here.

 

[Sokel]

Your application must not be typical HiFi listening. Nothing to see here.

I don't know typical or not,but is just an installation for music only (stereo).
Music is music every way you listen to it.
But you're right,nothing to see.

 

[RammisFrammis]

I don't know typical or not,but is just an installation for music only (stereo).
Music is music every way you listen to it.
But you're right,nothing to see.

I meant that 3KW of amplifier power is far outside of what any typical stereo listening would need. It is also far outside of tube territory. Class D is best there.

 

[Sokel]

I meant that 3KW of amplifier power is far outside of what any typical stereo listening would need. It is also far outside of tube territory. Class D is best there.

Class D,4 channels in total,yes.Just semi-active 3-way system,power is cheap these days.

 

[mmuetst]

I already have 3KW of amps,I think I'm ok

Are your speakers that poor in sensitivity?

 

[Sokel]

Are your speakers that poor in sensitivity?

Woofers are close to 83-84 db to 30-100Hz area,maybe even less.2x1200 @4 (2x600 @8,at least for minutes by specs) I know is an overkill but it's nice to have headroom (not that I ever went so far I think).

 

[ibenjamin]

Where is the decpitated Panther? It was well earned by Bob Carver! He signed the chassis after all. I'll be listening to this instead... Keep up the great work Amir.

 

[mmuetst]

Woofers are close to 83-84 db to 30-100Hz area,maybe even less.2x1200 @4 (2x600 @8,at least for minutes by specs) I know is an overkill but it's nice to have headroom (not that I ever went so far I think).

I have always fun when people come into my mancave en see my 300B monoblock amps. They think hundreds watts after they hear my set play, and than I tell them, nop only Max 6 watt but we just listening to approximately 1 a 2 watts only at this moment So I have headroom to….

 

[B&WTube]

That makes no sense whatever. And it gets worse from there.

I bet you wouldn’t talk like that in person. In real life if someone is nicely trying to explain their point, a gentleman who knew more who than another might say, “Here is where you are mistaken- the sag/slew rate is not affected because of xyz. Component tolerance doesn’t matter cause xyz. Etc.”
I already said I am happy to learn more about design. You can even PM me, or move this over to the VTA discussion for others to be educated (I am not the only one who thinks this way- there is a whole other forum that does)…sorry everyone for cluttering the this Carver discussion

 

[odarg64]

I bet you wouldn’t talk like that in person.

And therein lies the problem with Internet 'discussion.'

Well said.

 

[Multicore]

Sometimes I feel like people comment the measurements (which is fine and the right way to go,I do measure stuff myself and it's fun) but having never listened to a tube amp

I sure hope it wasn't my remark that gave you that feeling.

Sometimes I think that's is not engineering gone wrong but this result is intentional.And if that's their goal is fine by me.
It's not high fidelity by today's standards but it's fun!

Of course it is. I just want that fun to be: 1. more controllable, i.e. knobs and switches to dial in the right distortions for the program material, and 2. less expensive so more people share the fun.

 

[SIY]

I bet you wouldn’t talk like that in person. In real life if someone is nicely trying to explain their point, a gentleman who knew more who than another might say, “Here is where you are mistaken- the sag/slew rate is not affected because of xyz. Component tolerance doesn’t matter cause xyz. Etc.”

That assumes you have a basic grasp of the concepts you're trying to talk about.

 

[mhardy6647]

And therein lies the problem with Internet 'discussion.'

Well said.

It's a calling, you know?

Duty Calls

xkcd.com

That assumes you have a basic grasp of the concepts you're trying to talk about.

In fairness, in real life, a poorly-equipped debater (e.g., me, when it comes to much discussed here, at the level at which it's discussed) could kind of read the room... and might have the insight and prudence to just listen and observe.

 

[odarg64]

It's a calling, you know?

Duty Calls

xkcd.com

In fairness, in real life, a poorly-equipped debater (e.g., me, when it comes to much discussed here, at the level at which it's discussed) could kind of read the room... and might have the insight and prudence to just listen and observe.

Sorry, not a good enough reason for the other forum member to be a jerk. Once again, the ignore feature comes in handy.