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Carver Crimson 275 Measurements

MakeMineVinyl

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Not really vintage - they are Russian mil-spec K40Y-9 paper-in-oil caps. Good enough for a MiG, good enough for an amp. ;)

(Note: they look a bit funky because they're in heat-shrink tubing as they have metal bodies - trying to avoid letting out any magic smoke)
I use 'merican mil-spec paper in oil caps in my ST-70, MKIIIs and ST-35. They're military surplus and I'm sure they were originally intended for some implement of destruction, probably against the Russian military paper-in-oil caps. o_O
 

Zackthedog

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Zack, I would never besmirch John Curl, God knows I bought enough of his equipment. I just think it is funny every reference about the man starts out "the legendary John Curl." He is a much more modest gentleman than that! And I totally agree with honest measurements. If the amp is seriously less powered than advertised I will look for something else. I am not lying though when I tell you these LFT 8b's and this amp keep me up past my bedtime.
I appreciate your response. I don't know that you need to look for something else--if the amp satisfies, it does. Mine certainly does. ;-) The Carver could be doing many things right for you--enough to outweigh the deficits.
 

Thermionics

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I use 'merican mil-spec paper in oil caps in my ST-70, MKIIIs and ST-35. They're military surplus and I'm sure they were originally intended for some implement of destruction, probably against the Russian military paper-in-oil caps. o_O
rocky4punch.gif
 

anmpr1

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I use 'merican mil-spec paper in oil caps in my ST-70, MKIIIs and ST-35. They're military surplus and I'm sure they were originally intended for some implement of destruction, probably against the Russian military paper-in-oil caps. o_O
Shuguang 6V6GT. Stealthy. Designed for black ops...

shuguang.jpg
 

Martin

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Good evening all. I have been following this thread with a great deal of interest. Everyone here who has owned a Carver Crimson 275 amp (with a serial #) please raise your hand. I will wait. I do have the amp - I've owned it for 6 months now. As I write this I am listing to Sade singing "Hang On To Your Love." I am using a Schitt Freya+ preamp and amazingly I am listening to the music through Eminent Technology LFT 8b speakers which require a minimum of 75 Watts. Excuse me a moment. I have to turn this down. I can't hear myself think. That's better. To paraphrase Sienfeld, the sound is real and it is spectacular! I have no idea what Amir will find. Maybe it is a puny 15 watt per channel rip off. I don't know. I would want to put down my torches and pitchforks until I got a definite answer or heard the amp for myself. In the interest of full disclosure, I had run the bass with a SS Parasound amp. I disconnected that, increased the bias just to see of the amp could pull it off. Anyone want to buy a Parasound 23+ amp? It was designed by a man whose first name is apparently "Legendary" :)

Your Eminent Technology LFT 8b speakers that “require” 75 watts are 83dB (1W/1m) efficient. They will play plenty loud with 15 watts.

Martin
 

raindance

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Shuguang 6V6GT. Stealthy. Designed for black ops...

View attachment 178991
These are good tubes. I used to have an amp that used them as drivers for EL34's. When I sold the amp the buyer asked for them to be replaced by something that wasn't Chinese, so they're still sitting in my attic collection.
 

anmpr1

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These are good tubes. I used to have an amp that used them as drivers for EL34's. When I sold the amp the buyer asked for them to be replaced by something that wasn't Chinese, so they're still sitting in my attic collection.
Electrically they are fine. The only thing I don't like about them is that you can't see the glow very well. It's not a problem if they are hanging upside down in the back of your Mesa Boogie. But in your hi-fi? Really, if you are going to go glass, you want that orange glow once the lights grow dim. Unless you are a Mac owner. Then you have green LEDs, to pacify your sensibility. :)
 

audioholic63

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Your Eminent Technology LFT 8b speakers that “require” 75 watts are 83dB (1W/1m) efficient. They will play plenty loud with 15 watts.

Martin
The "required" wattage is a shifting target. I think Bruce put those specs out there to discourage prospective buyers from trying to run them with the imaginary wattage from most mid-line multichannel AVRs. As they present a fairly stable 8 ohm load they are pretty tube friendly. Running from my old Sunfire Cinema Grand biamped at a theoretical 400wpc vs a 60 watt Adcom, gets loud but one sounds clearly better than the other. Running my Cary SLM100's in UL (113wpc) vs Triod (50wpc), no appreciable difference in SQ or LF control.
 

atmasphere

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Not all Edcor iron has blue bobbins.
Yes. My point was this is not an off-the shelf item of their current catalog. Take a look at their catalog:
The ones with the end bells are their higher performance units as best I can make out. I built a low power amp using one of their 10-watt units and it had good bandwidth- well past 100KHz. I can't speak for the ones without end bells. Their website looks different from when I did that project a year and a half ago. At that time the transformers with end bells had their own page.
Something I'd not thought about until now is the photos look generic...
 
OP
paulbottlehead

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A part of me suspects that those blue bobbins may have just been more trouble than they are worth.

The higher dollar Edcor iron can perform quite well, but you get what you pay for. I think Edcor does a good job of offering a wide selection and providing enough data to show what you're getting by spending a little more money. There are other options at far higher prices where this information is not so willingly given!
 

oldtexasdog

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Much like Jpahere experience, I run my B&W 805's bi-amped with a pair of Carver 275's and even though the B&W speakers are power hungry they play very nice with excellent dynamics. If I use just one 275 they still sound great but don't have as much of the dynamics I like. I have built several EL84 and 6V6 15 watt per channel tube amps and when I tried to run the B&W's with them they were anemic and flat with no dynamics while on more efficient speakers they played with aplomb. So I have to believe there is more punch than 15 watts to the 275 just from my listening experience?
 

Zackthedog

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Yes. My point was this is not an off-the shelf item of their current catalog. Take a look at their catalog:
The ones with the end bells are their higher performance units as best I can make out. I built a low power amp using one of their 10-watt units and it had good bandwidth- well past 100KHz. I can't speak for the ones without end bells. Their website looks different from when I did that project a year and a half ago. At that time the transformers with end bells had their own page.
Something I'd not thought about until now is the photos look generic...
Interesting. I might buy a pair of their 10K/30W outputs and see how they hold up in my Williamson amps. If they're stable enough, it would be a good option for building a classic triode or UL Williamson.
 

Zackthedog

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Much like Jpahere experience, I run my B&W 805's bi-amped with a pair of Carver 275's and even though the B&W speakers are power hungry they play very nice with excellent dynamics. If I use just one 275 they still sound great but don't have as much of the dynamics I like. I have built several EL84 and 6V6 15 watt per channel tube amps and when I tried to run the B&W's with them they were anemic and flat with no dynamics while on more efficient speakers they played with aplomb. So I have to believe there is more punch than 15 watts to the 275 just from my listening experience?
Well, we know the amp can produce considerable power in the mid-band, so if you're bi-amping there shouldn't be a problem. Full-range wasn't as dynamic, you say, and that's where the issue of living up to the advertised specs comes in.
 
OP
paulbottlehead

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Much like Jpahere experience, I run my B&W 805's bi-amped with a pair of Carver 275's and even though the B&W speakers are power hungry they play very nice with excellent dynamics. If I use just one 275 they still sound great but don't have as much of the dynamics I like. I have built several EL84 and 6V6 15 watt per channel tube amps and when I tried to run the B&W's with them they were anemic and flat with no dynamics while on more efficient speakers they played with aplomb. So I have to believe there is more punch than 15 watts to the 275 just from my listening experience?
There is more than 15W available from these amps if you're talking about higher THD and you stay away from low frequency content.

Anecdotally I know tons of people using 87dB sensitive speakers on 2-4W amps who are quite happy with the output level from their systems.
 

atmasphere

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Interesting. I might buy a pair of their 10K/30W outputs and see how they hold up in my Williamson amps. If they're stable enough, it would be a good option for building a classic triode or UL Williamson.
You pay for them and they may take a while to deliver. Last time took 4 months. You can get higher quality transformers (IMO) from Heyboer
Don't be put off thinking their website was composed in Crayolawrite 1.0. They take a while too. That's how it is during a pandemic, apparently.

Mercury Magnetics also makes nice stuff. I'd not be surprised to find these three manufacturers make 90% of the musical instrument output transformers made in the US.

They do a lot of 'hifi' stuff too.
 

SIY

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Don't be put off thinking their website was composed in Crayolawrite 1.0. They take a while too. That's how it is during a pandemic, apparently.
Their downloadable "Specifications" Excel sheet is a revelation.
 

LTig

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View attachment 178908
Here's the amp hooked up to a test woofer with the speaker - terminal floating.
View attachment 178907
Here is the amp playing into the same woofer at the same level but with a clip lead connecting speaker - to the shell of an RCA jack.

So there is a difference that's not substantial and very much frequency dependent. While I can measure this here pretty easily, it inspired me to look at some tests into an actual woofer (a little 3" Hivi).

At 1% THD/40Hz, I can get about 600mV (not going to talk about power since the impedance curve is all over the place) with the speaker - floating. If I put a clip lead from speaker - to the shell of an RCA jack, that number goes up to around 720mV.

If I try this again at 1% THD/250Hz, I can get 2.9V with speaker - floating and 3V with the speaker - grounded.

These are different, but I will leave it to others to properly quantify this in ways maybe I shouldn't ;)
Looks like connecting the speaker with the RCA shell decreases output impedance because the output is higher where the speaker impedance is low, probably due to higher negative feedback. I would therefore recommend to use it as such - more power, less FR dependency, less THD.
 

Zackthedog

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There seems to be some confusion creeping into this discussion. Regardless of subjective listening experiences, the power and output transformers in the units that were examined fall far short of the capability needed to meet this amplifier's specifications. Has that changed?

Jack
There's no confusion. Two owners have reported subjective experiences--and it seems that in both cases the amps fell short in exactly the way the measurements would suggest.
 
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