Carver Crimson 275 Review (Tube Amp)

[mhardy6647]

Doesn't Krohn-Hite make Bluetooth speakers now?

Just kidding......

You're thinking of McIntosh.

 

[Walter]

You're thinking of McIntosh.

 

[MakeMineVinyl]

You're thinking of McIntosh.

When McIntosh comes out with a "sound system" for the built-in speakers on an Android phone, we will be well and truly screwed.

 

[DSJR]

I think for many, including me, the most salient point and the entire 'justification' is simply that vacuum tube amplifiers are more entertaining to look at and appreciate as objects. There's really no further justification needed. If that doesn't register with a particular buyer, they should simply stick to solid state. And of story.

I honestly cannot for the life of me believe that this even a point of debate, because as humans (most of us anyway), we are subjective in most things we encounter, and nothing is going to change that, at least until we are all robots in the likeness of Jeff Bezos.

Doesn't explain the almost religious audiophile worship of Leben amps, where the valves seem hidden and the front panel a kind of reproduction of a 60's amp (maybe it's that).

 

[MakeMineVinyl]

Doesn't explain the almost religious audiophile worship of Leben amps, where the valves seem hidden and the front panel a kind of reproduction of a 60's amp (maybe it's that).

I have no idea what a Leben amp is. My ARC D76A amp has internal tubes but when I use it (not often) I turn it backwards to see the tubes sticking out the back.

 

[mhardy6647]

When McIntosh comes out with a "sound system" for the built-in speakers on an Android phone, we will be well and truly screwed.

Maybe they'll partner with Klipsch and offer a greener solution...

or...

 

[mhardy6647]

I have no idea what a Leben amp is. My ARC D76A amp has internal tubes but when I use it (not often) I turn it backwards to see the tubes sticking out the back.

Leben Hi-Fi Stereo Company

Leben Hi-Fi Stereo Company

lebenhifi.com

 

[SaltyCDogg]

It's a handsome looking beast and meets a lot of the criteria of good amp design.
- Gold and shiny (adds richness)
- Wood panels (help tame excessive brightness and give an earthy tone)
- Some lights (green and red, like Christmas!)
- Some knobs to play with and feel like you're really king of your castle.

 

[Greg P]

Doesn't explain the almost religious audiophile worship of Leben amps, where the valves seem hidden and the front panel a kind of reproduction of a 60's amp (maybe it's that).

They remind me a bit of my first integrated amp, a 1967 Fisher.

 

[anmpr1]

... the valves seem hidden and the front panel a kind of reproduction of a 60's amp (maybe it's that).

Some people are just not into ostentation. Much like the guy who order his Turbo S with badge deletion. Doesn't want to tell the world he's driving a 911 that costs more than the entire trailer park. A little humble goes a long way... Especially in these audiophool times we're living in.

 

[Blumlein 88]

Some people are just not into ostentation. Much like the guy who order his Turbo S with badge deletion. Doesn't want to tell the world he's driving a 911 that costs more than the entire trailer park. A little humble goes a long way... Especially in these audiophool times we're living in.

Oh come on now. Some of those double-wides cost almost what a 911 Turbo S does?

 

[anmpr1]

Oh come on now. Some of those double-wides cost almost what a 911 Turbo S does?

And singles, too...

Bowlus Road Chief

The most advanced light weight travel trailer in the world. Built with honest materials for a lifetime of adventures.

bowlus.com

 

[AdamG]

A little humble goes a long way...

On the Internet? Now you are seeking a Miracle of unprecedented proportion.

 

[JohnVF]

It's a handsome looking beast and meets a lot of the criteria of good amp design.
- Gold and shiny (adds richness)
- Wood panels (help tame excessive brightness and give an earthy tone)
- Some lights (green and red, like Christmas!)
- Some knobs to play with and feel like you're really king of your castle.

As the owner of one I agree with the above. It has all the right cues. And to explain, I keep it around because I like using it and I think its pretty. Not all of my systems are for any sort of concentrated listening. Some things I like just because of what they are and this little amp is one of them. As for its construction, its sound and has nice output transformers. The man behind it owns a company that makes such things, and he was a former engineer at Luxman back in the day. It measures quite poorly compared to my other amps, but that's not really the point of such things. Also, its a real pain in the behind to find speakers for it. I don't like horn speakers, in general, and most other efficient speakers are too large for the 'third tier system that just looks good and is nice to use' camp.

What does this have to do with the Carver? Well, the Leben is similarly powered, at one time it was similarly priced, but in my opinion offers a lot more value for the money and it doesn't outright lie about what it is and what it can do.

 

[egellings]

I like my iron right out there, not hidden in cans.

 

[teched58]

The Audiogon thread on the Carver 275, in which they had been mirroring the test results here and the statements from Bob and Jim, has been take down:

https://forum.audiogon.com/discussions/peeking-inside-a-carver-crimson-275-tube-amplifier

"This discussion has been removed. One of our moderators or admins have removed this discussion."

 

[atmasphere]

I have found the opposite to be true, FR errors are much easier for me to hear than distortion. When I try the "online distortion tests" with music it has to get to 5% or more before I can hear it while I can easily hear a 1 or 2 dB FR change. Do you have any documentation to back up your assertion that the ear is more sensitive to distortion than FR?


Again my experience does not agree. Amps with rising distortion over 10 Khz are almost universal for the reasons you state i.e. less feedback for high frequencies. However I find the second harmonic of a 10 Khz fundamental completely inaudible as it is 20 Khz which is beyond my hearing. Can you link to any documentation about the sensitivity of human hearing to ultrasonic content. I have seen some and most is inconclusive at best.

The rise in distortion is variable for all amps- that depends on their GBP. But I think you are missing a couple of things, the first of which is that most amps made in the last 60 years have insufficient feedback to really get the job done. If you refer to Norman Crowhurst (also Baxandall), who was writing about this problem 60 years ago, what happens is thru a process of bifurcation due to non-linearities at the feedback node, feedback will generate both harmonic and inharmonic noise which becomes part of the noise floor of the amplifier. So if you have a signal a 1000Hz you will see increased harmonics at 3-7KHz, inside the most sensitive area of human hearing (Fletcher-Munson). The rise in distortion at higher frequencies is a complication.

To solve this problem you need a lot of feedback and a lot of GBP to go along with it (see Bruno Putzeys' writings on the matter https://linearaudio.net/sites/linearaudio.net/files/volume1bp.pdf)
His article is pretty good and outlines the matter pretty well.

I agree - and this is exactly what many amps with low negative feedback deliver when connected to a typical loudspeaker: due to the high output impedance you get kind of a small loudness curve which even in a blind test many people would prefer.

^^ This is what I'm talking about. The area where this gets critical is usually in the mids and highs where people perceive 'detail'.

Or it might not. Look at the values- they are really low. I'd want to see some evidence that an amp with distortion rising to, say, 0.05% at 20kHz will sound "bright" or audibly different than an amp with distortion ten or a hundred times lower.

Most of that is anecdotal on my part- the problem here is that certain amps get a reputation for being bright- and you have to ask yourself why that is when the amp tests perfectly flat on the bench and has a damping factor of over 100. Its clearly not coming from a frequency response error!

When you look at the specs, 0.01% is common. But you want to keep in mind that value was probably obtained at 100Hz and is not indicative of what it might be at 1KHz or 5KHz.

IMO/IME the distortion has to be a lot lower 0.001 or less before the signal itself is able to mask the distortion and prevent brightness. Put another way, the evidence is all around us. I've been doing this for over 47 years now and I'm well aware that people don't like the determination of 'its bright' being leveled at their amplifiers! The first thing to really grasp though is that the ear is so keenly sensitive to the higher orders and this simple fact has gone widely ignored in the last 60 years by the mainstream audio industry.

We have only to look at the fact that tubes are still around for 'hifi' to see that this is true. The main reason audiophiles support tube amplifiers and tube production is the brightness they perceive in solid state amps. This should not in any way be controversial. I suspect you may have already read Bruno's article above, but if you've not, give it a read!

When McIntosh comes out with a "sound system" for the built-in speakers on an Android phone, we will be well and truly screwed.

No we aren't- they will simply have a cause for being irrelevant.

 

[Blumlein 88]

The rise in distortion is variable for all amps- that depends on their GBP. But I think you are missing a couple of things, the first of which is that most amps made in the last 60 years have insufficient feedback to really get the job done. If you refer to Norman Crowhurst (also Baxandall), who was writing about this problem 60 years ago, what happens is thru a process of bifurcation due to non-linearities at the feedback node, feedback will generate both harmonic and inharmonic noise which becomes part of the noise floor of the amplifier. So if you have a signal a 1000Hz you will see increased harmonics at 3-7KHz, inside the most sensitive area of human hearing (Fletcher-Munson). The rise in distortion at higher frequencies is a complication.

To solve this problem you need a lot of feedback and a lot of GBP to go along with it (see Bruno Putzeys' writings on the matter https://linearaudio.net/sites/linearaudio.net/files/volume1bp.pdf)
His article is pretty good and outlines the matter pretty well.

^^ This is what I'm talking about. The area where this gets critical is usually in the mids and highs where people perceive 'detail'.

Most of that is anecdotal on my part- the problem here is that certain amps get a reputation for being bright- and you have to ask yourself why that is when the amp tests perfectly flat on the bench and has a damping factor of over 100. Its clearly not coming from a frequency response error!

When you look at the specs, 0.01% is common. But you want to keep in mind that value was probably obtained at 100Hz and is not indicative of what it might be at 1KHz or 5KHz.

IMO/IME the distortion has to be a lot lower 0.001 or less before the signal itself is able to mask the distortion and prevent brightness. Put another way, the evidence is all around us. I've been doing this for over 47 years now and I'm well aware that people don't like the determination of 'its bright' being leveled at their amplifiers! The first thing to really grasp though is that the ear is so keenly sensitive to the higher orders and this simple fact has gone widely ignored in the last 60 years by the mainstream audio industry.

We have only to look at the fact that tubes are still around for 'hifi' to see that this is true. The main reason audiophiles support tube amplifiers and tube production is the brightness they perceive in solid state amps. This should not in any way be controversial. I suspect you may have already read Bruno's article above, but if you've not, give it a read!

No we aren't- they will simply have a cause for being irrelevant.

Since when is it common to measure distortion at 100 hz? 1 khz is the most common. And despite your protestations plenty of independent measurements cover the whole 20hz-20khz range. So to indicate higher order harmonic distortion is ignored due to measuring at 100 hz, you are making up something to support your argument. One which has not been convincing so far.

SIY has asked for any data that very low high order harmonic distortion is audible and all you have are misdirections about 100 hz measurements and anecdotal reports of bright amplifiers. I'd like some bright data thanks.

 

[atmasphere]

Since when is it common to measure distortion at 100 hz? 1 khz is the most common. And despite your protestations plenty of independent measurements cover the whole 20hz-20khz range. So to indicate higher order harmonic distortion is ignored due to measuring at 100 hz, you are making up something to support your argument. One which has not been convincing so far.

SIY has asked for any data that very low high order harmonic distortion is audible and all you have are misdirections about 100 hz measurements and anecdotal reports of bright amplifiers. I'd like some bright data thanks.

Stereophile often uses 100Hz. Please read Bruno's article if you have not already done so.

 

[Blumlein 88]

Stereophile often uses 100Hz. Please read Bruno's article if you have not already done so.

I've read Bruno's article.
Stereophile will often use a 50 hz test for seeing how the low end of tube amps hold up . They do 1 khz also and 1 khz for any amp I've seen them review. Not once do I remember a 100 hz tone test. Maybe there have been some, if so you could point one out. It darn sure isn't common or the norm for them.