Going Big class A?

Alrainbow

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A sliding bias is around a long time and done a couple of ways
One is lower bias at idle and ramp up when music plays
Another is adjust to remain Biased the same cold and hot meaning regulated
I don’t build nor do I know maker technics either
But an amp still must have a threshold where it’s no longer in class a
If pass has another method then let’s ask him he is a nice man.
Surely knows more about amps than I ever will. It looking at the size of an amp , it’s transformers and it’s best sinks Does give clues. Pass seems to low class as a guess.
But overall we are still arguing over what is class a and ab this is a bit silly I feel.
Look st the size of my no 33 amps and still not hundreds of watts in class a
Idle is about 9 amps so divide by two as they are fully balanced and do the math from there.
 

Alrainbow

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Lol no it’s most likly not. Much less class a and when imp is halved class a is 1/4
Amp makers love claiming class a but while it is
Class A they don’t claim stats of its. Lamm is honest and they use a varying output buss voltage to swing from 8 to 4 ohms

8 ohms source amp
4 ohms is corrent source amp
Mine are true voltage source always it’s one reason they are huge
 

LL21

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interesting, so when Gryphon says 160 watts pure Class A into 8 ohms, do you think it is? They print reams of literature about they are truly Class A when they say they are...and (as you say) how few manufacturers truly are.
 

Alrainbow

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I mean no offense to anyone or there audio stuff but it’s just math
It’s a marketing ploy is all and most don’t know or care lol and that’s fine
It if one asks we should help each other and learn it’s how i did.
The amps you posted of what is there idle current even if playing music low this is enough to make a sliding bias amp turn on to class a
 

KeithR

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So if my amps rarely leave class A and Alrainbow writes that class A is not as dynamic as class AB, why does my system sound so dynamic? It seems class A can deliver dynamics. Perhaps I should try an X.5 amp to see if it is more dynamic.

I'd bet a decent sum of money the 600.8s would outperform the Class A amps on your chosen speaker. Get Reno to send you a pair.
 

LL21

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...re-reading Gryphon, they do say they do not use any sliding or auto-bias when in "High Bias Mode"...it is 160 watts Pure Class A into 8 ohms whether there is signal or not signal. it just burns 800 watts of power from the wall as soon as you turn it on because it is ready with 160watts, Class A into 8ohms. Perhaps Phil O'Oanlon can chime in here.

just here to learn.
 

LL21

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Alrainbow

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Ty looking it up now looks like a monster has 96 transistors
So 33 per channel and 16 per side
Still a big boy post later.
 

LL21

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thank you for taking the time!
 

PeterA

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I'd bet a decent sum of money the 600.8s would outperform the Class A amps on your chosen speaker. Get Reno to send you a pair.

Thanks Keith. I'll gladly call Mark if you agree to pay for the amps or shipping if I return them. They may be more dynamic than what I now have, but that does not mean they will sound better in every way. That is why Pass makes the X and XA lines, and for a while both the .5 and .8.
 

LL21

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I'd bet a decent sum of money the 600.8s would outperform the Class A amps on your chosen speaker. Get Reno to send you a pair.

Thanks Keith. I'll gladly call Mark if you agree to pay for the amps or shipping if I return them. They may be more dynamic than what I now have, but that does not mean they will sound better in every way. That is why Pass makes the X and XA lines, and for a while both the .5 and .8.

Do we see a wager starting to shape up here? What do you pay Keith if he's right? You pay full shipping since you're buying...plus you pay him 2x the shipping cost for his wager? ;)

You might even get the dealer/distributor to participate if you have a good relationship. He pays shipping to you if you are serious and perhaps have been a loyal customer generally...obviously you/Keith pays if you return it.
 

microstrip

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...re-reading Gryphon, they do say they do not use any sliding or auto-bias when in "High Bias Mode"...it is 160 watts Pure Class A into 8 ohms whether there is signal or not signal. it just burns 800 watts of power from the wall as soon as you turn it on because it is ready with 160watts, Class A into 8ohms. Perhaps Phil O'Oanlon can chime in here.

just here to learn.

Sorry it is 160W of class A when there is an adequate signal, 800 W of power from the wall whether there is signal or not signal. No signal, no power output! :)

It is a typical value for a push pull class A - idle power is a little more than four times the maximum output. Considering the high impedance of the Grand Slam and its high efficiency it will be almost all the time playing class A in your system!
 

LL21

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Sorry it is 160W of class A when there is an adequate signal, 800 W of power from the wall whether there is signal or not signal. No signal, no power output! :)

It is a typical value for a push pull class A - idle power is a little more than four times the maximum output. Considering the high impedance of the Grand Slam and its high efficiency it will be almost all the time playing class A in your system!

Yes, definitely 800 watts no matter what...so may as well play the music! Interestingly, given the efficiency of the speaker...i originally thought i could play at much lower bias levels in class A (ie, you can switch between 25%, 50% or 100% class A)...but there was a big difference at 25% and still a recognizeable difference at 75% which i thought for sure would not be right.

In any event, Gryphon writes in their manual, "...160 watts Pure Class A...this bias level will be maintained even when music is absent..." Is this right?
 

PeterA

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Do we see a wager starting to shape up here? What do you pay Keith if he's right? You pay full shipping since you're buying...plus you pay him 2x the shipping cost for his wager? ;)

You might even get the dealer/distributor to participate if you have a good relationship. He pays shipping to you if you are serious and perhaps have been a loyal customer generally...obviously you/Keith pays if you return it.

I've only made one important wager recently Lloyd. It was in Nov. 2016. I was right. I'm much less certain about which of these amps I would prefer in my system, so I think I'll Pass. Keith may be correct about dynamics. With my former speakers, I preferred the .5 to the .8 after a direct comparison. I've never heard the X.8.
 

Alrainbow

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Can someone help me the math seems way off
Stereo idle is 500 watts so half for one channel
250!watts at lets say 25% at 8 ohms is about 62 watts class a still plenty but how do they arrive at 160!watts help me here please
 

LL21

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I've only made one important wager recently Lloyd. It was in Nov. 2016. I was right. I'm much less certain about which of these amps I would prefer in my system, so I think I'll Pass. Keith may be correct about dynamics. With my former speakers, I preferred the .5 to the .8 after a direct comparison. I've never heard the X.8.

Fair enough!
 

LL21

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Can someone help me the math seems way off
Stereo idle is 500 watts so half for one channel
250!watts at lets say 25% at 8 ohms is about 62 watts class a still plenty but how do they arrive at 160!watts help me here please

Perhaps that is their B setting...which is their Middle Setting (they say in the manual this is 70 watts Class A only). I thought Gryphon's technical people told me it burns about 700-800 watts at idle. In the Lo Setting, they say in the manual 30 watts class A, 180 watts Class A/B.
 

Alrainbow

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Going to bed guys still seems like a nice amp.
One last thing to consider bias has an effect on the sound not just coz of class so if it was me I would try but know about return rules
Amps and speakers are Always an interaction that must be heard and liked
How much are these amps anyway
 

LL21

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Going to bed guys still seems like a nice amp.
One last thing to consider bias has an effect on the sound not just coz of class so if it was me I would try but know about return rules
Amps and speakers are Always an interaction that must be heard and liked
How much are these amps anyway

too much! ;) I believe retail for the Colosseum (i bought deep discount 2nd hand!)...is $47K.
 

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