Hi
I just bought a used Supro 1600 Supreme. Great tone but was slightly disappointed at the lower-than-expected headroom/volume of a (supposedly) 25W amp. Then I wondered how a pair of 6V6s in cathode bias could possibly put out 25W?? Seems improbable, right?? Can anyone explain how that works?
Supro 1600 Supreme power rating
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Stevem
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Re: Supro 1600 Supreme power rating
Even with fixed bias as in a Deluxe reverb ( 6V6s) and with 420 volts on their plates these amps only attain some 18 watts of clean RMS power.
That amp is rated for 25 watts of peak power not clean I would bet, especially in cathode biased form!
If the amps OT has a 16 ohm tap you could add another speaker cab wired in series and then get near twice the volume before clipping takes place.
That amp is rated for 25 watts of peak power not clean I would bet, especially in cathode biased form!
If the amps OT has a 16 ohm tap you could add another speaker cab wired in series and then get near twice the volume before clipping takes place.
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Re: Supro 1600 Supreme power rating
Is this a Newer RI Supro?
They're liars. They have sketchy marketing. Make mistakes on bias. Advertise Made in USA, when they're Asian amps that just get some minor final assembly in the US. They call everything that's cathode biased 'Class A' and market that on all their amps as superior tone, so it's no surprise they're lying about the amp putting out 25 watts (Or they measured 'peak' to massage that number higher)
https://suprousa.com/1600-supreme/
"25 Watts Class A"
It's neither.
They're liars. They have sketchy marketing. Make mistakes on bias. Advertise Made in USA, when they're Asian amps that just get some minor final assembly in the US. They call everything that's cathode biased 'Class A' and market that on all their amps as superior tone, so it's no surprise they're lying about the amp putting out 25 watts (Or they measured 'peak' to massage that number higher)
https://suprousa.com/1600-supreme/
"25 Watts Class A"
It's neither.
It's true i've lost my marbles and i cant remember where i put them
Re: Supro 1600 Supreme power rating
Yeah, pure marketing hype for the frenzied Koolaid drinker
Re: Supro 1600 Supreme power rating
Hmm... I thought as much. The add says
"Supreme features a pair of parallel gain stages fed into a shared tone knob. This versatile, dual-input preamp allows two instruments to share the same combo amplifier, as well as providing the convenient option of plugging a single instrument into IN1+2, for double the gain."
I wonder if they're saying it's actually a 12W amp but when using both channels it's double the power?
"Supreme features a pair of parallel gain stages fed into a shared tone knob. This versatile, dual-input preamp allows two instruments to share the same combo amplifier, as well as providing the convenient option of plugging a single instrument into IN1+2, for double the gain."
I wonder if they're saying it's actually a 12W amp but when using both channels it's double the power?
Re: Supro 1600 Supreme power rating
Regrettably, no, it doesn't work like that. <sigh> I wish it were that easy. It reminds me of the old saying, I can tell you how to double your money real quick. Fold it in half!
With a pair of 6V6, it is likely making 15-18W and no more. If you need more volume, focus on the speaker. Get a more efficient speaker.
As Stevem notes, if it has 2 outputs, for example 8Ω and 16Ω , then you can use a 4Ω speaker into the 8Ω jack plus a 8Ω speaker into the 16Ω jack at the same time and not hurt the amp. This will give you more surface area of speaker and more perceived volume. One speaker can be the one in the amp cabinet and the other an auxiliary cabinet.
Re: Supro 1600 Supreme power rating
The power amp is the power amp, and can only put out so much no matter what you do to the front end. And, if the amp is truly operating in Class A as they claim (again using the Operating Class as some kind of badge of pedigree), which it isn't, they aren't getting any where near 25W peak out of it. Running a pair of 6V6s in fixed bias Class AB with plate voltages at 460VDC and screens about 325VDC, you might get 22W peak out of them or so (e.g. Mark Huss 6V6 Plexi)
The only thing Class A here is the bullshit.
The only thing Class A here is the bullshit.
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Stevem
- Posts: 5144
- Joined: Fri Jan 24, 2014 3:01 pm
- Location: 1/3rd the way out one of the arms of the Milkyway.
Re: Supro 1600 Supreme power rating
Well, no, the preamp tubes have to be biased in class A.
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Of course! Insult partly retracted.