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.
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I was debating between the Carver 275 with a Mcintosh C47 preamp or a McIntosh MA-252 Integrated hybrid. After reading this post, if the transformers are only 17 WPC each (I believe there are 3), that still only gets to 51 aggregate assuming they are bridged. I love Bob Carver, but McIntosh seems to figure things out and they are made in the USA too. Niche brands often need to compromise their lower end products to reach better market share. I was stymied by the price of the Carver (only $2,750), but then I realized, like lower end REGA turntables, the product is built to a specific market  price, the compromises slip away as one moves up the particular manufacturer's product ladder. The Carver 350s are built like tanks but cost $9,500 for a reason. This Carver 275 is a nice entry level audiophile product (akin to solid state Rotel 1500 series units).

I'm buying the Mac: tried and true 100wpc @8ohms/160 @ 4---with a true .005 distortion level. 4 cozy USA tubes that glow green and create that nice warm sound. $4,500.00--done and done.

The Carver 350s are built like tanks but cost $9,500 for a reason. This Carver 275 is a nice entry level audiophile product (akin to solid state Rotel 1500 series units).

I’m buying the Mac: tried and true 100wpc @8ohms/160 @ 4---with a true .005 distortion level. 4 cozy USA tubes that glow green and create that nice warm sound. $4,500.00--done and done.

The focus has been squarely on the Crimson 275, deservedly so, but does anyone really trust that Carver Raven 350 now? It’s only 44 lbs per side (most certainly NOT built like a tank) and rated at 350 tube Watts per channel into 8 ohms; 400 per ch into 4 ohms! That power rating represents the KT120 tubes running at around their limit (which is FAR from reality on the 275). That’s maybe even more optimistic a power rating than the 275! At 44 lbs there also has to be a lot of air under those huge transformer covers. The most credible spec on its sheet is its (near) $10K price.

Compare to the Rogue Audio Apollos which are 100 lbs per side and rated (quite likely an honest) 250 Watt /ch. Or the M180, rated 180 Watt / ch, 55 lbs a side, and about $3K less than the Raven 350. I would bet the M180 easily out-powers the 350 on a bench.

Anyways, you made a good choice going for Mac over Carver!