Peeking inside a Carver Crimson 275 Tube Amplifier


So, I just had to pop the hood on the Carver Crimson 275 tube amplifier. I was so curious as to how this little guy weighs so little and sounds so lovely.

  • The layout is simple and clean looking. Unlike the larger monoblocks (that cost $10k), this model uses a PCB.
  • The DC restorer circuit is nicely off to one side and out of the way. It doesn’t look all that complicated but I’m no electrical engineer. Why don’t more designers use this feature? It allows the power tubes to idle around 9.75w. Amazingly efficient.
  • The amp has very good planned out ventilation and spacing. No parts are on top of each other.
  • Most of the parts quality is good. There’s a host of Dale resistors, what look like Takmans, nice RCA jacks, heavy teflon hookup wire, and so on.
  • Some of the parts quality is questionable. There’s some cheap Suntan (Hong Kong mfr.) film caps coupled to the power tubes and some no name caps linked to the gain signal tubes. I was not happy to see those, but I very much understand building stuff to a price point.
Overall, this is a very tidy build and construction by the Wyred4Sound plant in California is A grade. I’m wondering a few things.

Does the sound quality of this amp bear a relationship to the fact that there’s not too much going on in the unit? There are very few caps--from what this humble hobbyist can tell--in the signal chain. And, none of these caps are even what many would consider decent quality--i.e. they aren’t WIMA level, just generic. This amplifier beat out a PrimaLuna Dialogue HP (in my room/to my ears...much love for what PrimaLuna does). When I explored the innards of the PrimaLuna, it was cramped, busy and had so much going on--a way more complicated design.

Is it possible that Bob Carver, who many regard as a wily electronics expert, is able to truly tweak the sound by adding a resistor here or there, etc.? Surely all designers are doing this, but is he just really adroit at this? I wonder this because while some parts quality is very good to excellent, I was shocked to see the Suntan caps. They might be cheaper than some of the Dale resistors in the unit. I should note that Carver reportedly designed this amp and others similar with Tim de Paravicini--no slouch indeed!

I have described the sound of this amp as delicious. It’s that musical and good. But, as our esteemed member jjss [ @jjss ] pointed out in his review, he wondered if the sound quality could be improved further still. He detected a tiny amount of sheen here and there [I cannot recall his exact words.] even though he loved it like I do.

I may extract the two .22uF caps that look to be dealing with signal related to the 12at7 gain tubes and do a quick listening test.
128x128jbhiller

@fmalitz Frank thank you for this response.. however I’d like for you to respond to why the 275 does not even come close to its specs? Why does an amp spec’d for 75 watts per channel only put out 17 wpc? Why are the transformer covers very large fake covers over very small transformers that are only capable of 15-18 wpc?

I almost bought a 275. I am glad I did not, seeing how I know from experience that my speakers need at minimum 75 to 100wpc. Can you imagine how angry I would have been finding out it can only put out 17 wpc?

 

I visit Audiogon often but hardly ever post.. I was moved to post this question. I’d like an honest answer.

The 275 is under scrutiny on at least four other audio forums as we speak. Interestingly on one, the negative comments are largely removed. I’m happy here we can have a warranted inquiry without censorship. I’m not sure why the forum mods are protecting truth on this other audio forum.. but the real measurements and specs are all over the internet like wild fire. Multiple sources sharing the same failures to meet published spec in epic proportion.

As a previous fan and owner of Carver products I’m anxious to hear the other side. My confidence has waned and I’m becoming bias with facts that will be tough to refute or explain.

Post removed 

@funky54,  I'm curious to read the fire from other cites/posts.  Can you put up some links?  

 

fiesta75,  Can you tell us why you believe the 275 is a disappointment?  Did you/do you own one?  What experience do you have with the amp?  What is it about the amp that let you down?  

 

I have no comment on the unit's power output in watts.  I have 102dB sensitive speakers so I don't need much juice.  

Let it rip folks!  Transparency is a great policy.  

Frank, looks like you have some things to answer!