Carver Crimson 275 Review (Tube Amp)

[cardan]

I read a story that the Chevy Nova failed to sell well when it was introduced in South America because “no va” in Spanish means “it doesn’t go.”

Not true.
The Chevy Nova didn't fail because of the name "Nova". Everyone in Latin America, particularly in Colombia knew Nova meant "New" (from Latin). "No va" was more of a joke, not more than that.
The Chevy Nova failed in South America not because of the name "Nova" but because at that time (70's and early 80's) for years Renault (French car manufacturer) had been selling great little cars (Renault 4, 6, 9, 12 and others) with good ground clearance and at a very affordable price, most cheaper than the Chevy Nova. Chevrolet was not a strong brand there during those years.
Renault parts were easy to get and just about any mechanic knew how to repair Renaults. Fiat, Simca and even Mazdas were very popular during the 70's and 80's too. Competition was tough for Chevy.
I lived there during that time.

 

[egellings]

Over and Out?

Not Bob....

You're either 'over' or you're 'out'. You can't be both at once.

 

[fpitas]

It does look pretty cool. Pity there seems to be a problem with the output transformers. Otherwise, somebody could re-design it into a competent amp.

 

[egellings]

I recall seeing a photo of one of the amplifiers in which the cover on the output transformer's casing was removed, revealing a little walnut of a transformer. I don't know if that was a fake or if that is actually what is present on the amplifiers.

 

[fpitas]

I recall seeing a photo of one of the amplifiers in which the cover on the output transformer's casing was removed, revealing a little walnut of a transformer. I don't know if that was a fake or if that is actually what is present on the amplifiers.

What with the weird behavior at 20Hz, I tend to believe the walnut theory.

 

[DonH56]

You're either 'over' or you're 'out'. You can't be both at once.

Over and out is old radio speak. "Over" when you complete your time speaking (transmitting) and are ready to receive (i.e. for the other side to begin transmitting); "out" when you are done and signing off. Thus "over and out" means you are done and going off-air, or at least away from the current conversation.

 

[Billy Budapest]

Over and out is old radio speak. "Over" when you complete your time speaking (transmitting) and are ready to receive (i.e. for the other side to begin transmitting); "out" when you are done and signing off. Thus "over and out" means you are done and going off-air, or at least away from the current conversation.

I mean, who DOESN’T know this? It’s like “10-4, good buddy!”—it’s in the vernacular.

 

[amirm]

I recall seeing a photo of one of the amplifiers in which the cover on the output transformer's casing was removed, revealing a little walnut of a transformer. I don't know if that was a fake or if that is actually what is present on the amplifiers.

It was true and what motivated this review to confirm actual performance.

 

[Mart68]

Over and out is old radio speak. "Over" when you complete your time speaking (transmitting) and are ready to receive (i.e. for the other side to begin transmitting); "out" when you are done and signing off. Thus "over and out" means you are done and going off-air, or at least away from the current conversation.

No, Egglings is correct. Either you're over, or your out. Not both at the same time. Out means you're ceasing receiving so there's no point saying 'over' to the other operator as well since if he now transmits you won't receive it. It's a common expression but technically incorrect.

 

[DonH56]

I mean, who DOESN’T know this? It’s like “10-4, good buddy!”—it’s in the vernacular.

LOL. A scary thought for us old-timers is how long ago the CB craze happened. And how little of that vernacular survived, and how little we understand of today's vernacular.

No, Egglings is correct. Either you're over, or your out. Not both at the same time. Out means you're ceasing receiving so there's no point saying 'over' to the other operator as well since if he now transmits you won't receive it. It's a common expression but technically incorrect.

I described it the way it was used for military, ham (amateur radio), and CB communications back when I was active in such things (decades ago). Over and out were different, and over and out meant you were done speaking and signing off. I am not sure I ever heard "out" without "over and" before it, but it's been a moment. Not arguing it was correct, but that was the usage taught and used in my experience. Experience varies, and mine is admittedly old, but I suppose none of this is really relevant to the amp in question.

 

[Bruce Morgen]

It was true and what motivated this review to confirm actual performance.

Can you provide that photo? Thanks in advance!

 

[amirm]

Can you provide that photo? Thanks in advance!

See https://www.audiosciencereview.com/...r-crimson-275-measurements.29271/post-1022280

 

[somebodyelse]

No, Egglings is correct. Either you're over, or your out. Not both at the same time. Out means you're ceasing receiving so there's no point saying 'over' to the other operator as well since if he now transmits you won't receive it. It's a common expression but technically incorrect.

I described it the way it was used for military, ham (amateur radio), and CB communications back when I was active in such things (decades ago). Over and out were different, and over and out meant you were done speaking and signing off. I am not sure I ever heard "out" without "over and" before it, but it's been a moment. Not arguing it was correct, but that was the usage taught and used in my experience. Experience varies, and mine is admittedly old, but I suppose none of this is really relevant to the amp in question.

I wonder whether there was a transatlantic or field-specific difference in radio convention. 'Over and out' on TV and film always used to annoy my grandfather because from his UK experience in WW2 and later marine VHF they were mutually exclusive. It's still that way in NATO per ACP125(G) page 3A-4, among other US and international civil and military standards. The ITU Guide to Radio Communications Standards for Emergency Responders even calls it out specifically in its definition for procedure word OUT:

This is the end of my transmission to you and no answer is
required or expected. (Since OVER and OUT have oppo-
site meanings, they are never used together

 

[Mart68]

I wonder whether there was a transatlantic or field-specific difference in radio convention. 'Over and out' on TV and film always used to annoy my grandfather because from his UK experience in WW2 and later marine VHF they were mutually exclusive. It's still that way in NATO per ACP125(G) page 3A-4, among other US and international civil and military standards. The ITU Guide to Radio Communications Standards for Emergency Responders even calls it out specifically in its definition for procedure word OUT:

It's possible that it was only standardised after WW2 I suppose. I always assumed it was something made up by some Hollywood scriptwriter, but maybe not.

 

[sergeauckland]

No, Egglings is correct. Either you're over, or your out. Not both at the same time. Out means you're ceasing receiving so there's no point saying 'over' to the other operator as well since if he now transmits you won't receive it. It's a common expression but technically incorrect.

Indeed so. The radio practice I was taught was to say 'Callsign Standing By' when the conversation was finished, but I was still receiving and listening. Over was between speech on a simplex connection, Callsign Out was when finished and no longer listening.

S.

 

[dfuller]

Coming back to this again for fun, this is why my initial comment:

This immediately made me suspicious. I have enough experience with guitar amps to know that a guitar amp (which is specced for roughly 5% THD at rated output power) would have at least a 4 amp if not a 5 amp fuse for that kind of tube complement and rated power output.

Says what it says.

I did some back-of-napkin math on how much power this thing should've been drawing just sitting there idling. There are some assumptions here, I don't know what the idle current was set to and I don't know the power supply efficiency.

6.3V x 1.7A x 4 KT120s = ~42.84W
6.3V x 0.3A x 3 small signal tubes = 5.67W

Total tube heater power draw = ~48.5W

KT120s are massively powerful receiving tubes, able to run at 60W plate dissipation. Assuming 50% of max PD quiescent current (quite low, but bear with me), 30W x4 = 120W B+ (plus a tiny bit for the small signal tubes, in the area of 1ma per section, and a little bit for the screen grids but this is pretty minimal)

So that's ~170W sitting there just idling, if not more depending on output section biasing (go up to 70% of max PD per tube and we're looking at 218W!)

Surprisingly, unregulated power supplies can be quite efficient, so let's be generous and say it's 90% efficient.

Idling, it's drawing about 187W. 1.5A of the fuse's 3A capacity, and that's being optimistic. It may well be up above 200W.

By comparison, the McIntosh MC275, which uses 4 KT88s and a smattering of 12AX7s and 12AT7s to reliably actually produce 2x 75W, uses 432 watts at maximum output power per McIntosh's own power draw ratings. Even subtracting off the ~54W of heater power, it's still drawing nearly 380W. There's no way to make this work on maximum 360W.