Valve amps are mostly class A - but regardless of that, their impedance matching output limts them to less that 50%.
The vast majority is for the output stage, same as any other amplifier - the rest of the amp is probably too low to be significant.
Hi, this Product is a 200W valve amp................
Blackstar Series One 200 Head | Guitar World
.....from the description that says it is heavy, -you tend to think that it must contain 50Hz transformers to provide the high-voltage tube supply.......
...but i happen to know that it contains a flyback SMPS switching at high frequency.
....dont ask me how i know that, i just know it does.
......So what do you think the flyback SMPS is needed for?
...if the high voltage tube supply is provided by the 50Hz trensformers, then why do they need a flyback SMPS as well?
Blackstar Series One 200 Head | Guitar World
.....from the description that says it is heavy, -you tend to think that it must contain 50Hz transformers to provide the high-voltage tube supply.......
...but i happen to know that it contains a flyback SMPS switching at high frequency.
....dont ask me how i know that, i just know it does.
......So what do you think the flyback SMPS is needed for?
...if the high voltage tube supply is provided by the 50Hz trensformers, then why do they need a flyback SMPS as well?
Probably for the tube heaters. A number of manufacturers are starting to use SMPSes for tube heaters as a cost-effective solution to getting quiet DC heaters in high-gain amps without having to resort to high-current regulation. They can also be pulled off the shelf, which is easier for some small manufacturers using point-to-point/turret board/similar construction than designing and building regulator PCBs.
This amp would appear to have a conventional linear PT and OT from the photos, so that's where my vote would go.
IN a tube amp, you can eliminate the power transformer with an SMPS, but that doesn't remove the need for an output transformer, so the amp will still be heavy. A 200w output transformer will not be light in weight.
A recent trend in guitar amps is to run the heaters in series. That way the same current powers all of them, instead of adding more current for each tube. Make a +/-24v split supply, then run a string of four 12AX7s across that 48vDC, for example. And those 24v rails then go on to make +/-15 for any op amps. Peavey Valve Kings run four 6L6 heaters in series, at 0.9A through them, then takes the three 12AX7s in the amp and parallels them in 6v mode. That makes a 0.9A total for the group, which conveniently can be placed in series with the 6L6s. One relatively low current 30v supply can heat them all. NO high current connetions between board to burn out.
SMPS can make any voltage you want it to. Thinking of the Crate V series, using SMPS, there are 450vDC for the B+, 6v for the heaters, a bias supply, and a low voltage for relays and SS stuff. All on one SMPS board.
A recent trend in guitar amps is to run the heaters in series. That way the same current powers all of them, instead of adding more current for each tube. Make a +/-24v split supply, then run a string of four 12AX7s across that 48vDC, for example. And those 24v rails then go on to make +/-15 for any op amps. Peavey Valve Kings run four 6L6 heaters in series, at 0.9A through them, then takes the three 12AX7s in the amp and parallels them in 6v mode. That makes a 0.9A total for the group, which conveniently can be placed in series with the 6L6s. One relatively low current 30v supply can heat them all. NO high current connetions between board to burn out.
SMPS can make any voltage you want it to. Thinking of the Crate V series, using SMPS, there are 450vDC for the B+, 6v for the heaters, a bias supply, and a low voltage for relays and SS stuff. All on one SMPS board.
Tube filaments are 6.3V, at reasonably high current if you include the power tubes into the calculation. That's easy on AC which is what guitar amps have historically used, but if you get a high gain amp and want to get rid of hum induced via the heaters then you want to run them from a very quiet regulated DC supply. That suddenly becomes quite complicated to get a DC supply at the current required that's actually quieter than the AC supply it's replacing. This is why a number of manufacturers are now pulling stock SMPSes off the shelf and using them, because it's cheaper and easier for them than dealing with the hassle of designing a good regulator.
They are also world voltage as standard usually, and mean that the filament winding isn't required on the PT which brings down the PT cost by removing the largest gauge copper winding from it.
60lbs doesn't seem too bad for this amp. It needs hefty transformers and a correspondingly large and strong chassis, and then a headshell too. The Ampeg SVT weighs in at 85lbs!
They are also world voltage as standard usually, and mean that the filament winding isn't required on the PT which brings down the PT cost by removing the largest gauge copper winding from it.
60lbs doesn't seem too bad for this amp. It needs hefty transformers and a correspondingly large and strong chassis, and then a headshell too. The Ampeg SVT weighs in at 85lbs!
Assuming it actually does have a SMPSU, there's no need for it to have a 50Hz mains transformer as well - the SMPSU is perfectly capable of providing all the supplies (and far more accurately than a 50Hz transformer).
It will however still have a whopping great big output transformer, which will make it heavy.
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