The colourful chef from Scotland with the various restaraunt series on TV is currently touring Australia and there is a new expression emerging down here. People are starting to refer to "Gordon Ramsey moments!" To which he replied that how could we, Australians of all people, possibly take offence! Fair point I reckon.
Re: Re: whats makes sense to have class A amp?
That's false, a class A amp can be run with split supplies and have either global feedback or a servo to get rid of the offset. Anyways the output cap may help if loudspeaker impedance dips too low at lf.
Having more or less bass depends on the amp, not the class, but if i was to make an amp for a sub i would obviously use class D.
nigelwright7557 said:
That's false, a class A amp can be run with split supplies and have either global feedback or a servo to get rid of the offset. Anyways the output cap may help if loudspeaker impedance dips too low at lf.
Having more or less bass depends on the amp, not the class, but if i was to make an amp for a sub i would obviously use class D.
To make fair comparison between classA and classAB, we can choose a topology that can be made classA and classAB by just turning the bias pot. Make 2 of this amp, and bias one in class A (A bias) and another one in AB (mA bias).
Since the topology, the supply, the PCB all the same, this way we can know what is the difference between classA and classAB.
ClassAB has x-over distortion looped in feedback (in theory=bad), but to some people this reveals itself as "enhanched trebles" and "more dynamic sound" which (surprisingly) they prefer more.
Since the topology, the supply, the PCB all the same, this way we can know what is the difference between classA and classAB.
ClassAB has x-over distortion looped in feedback (in theory=bad), but to some people this reveals itself as "enhanched trebles" and "more dynamic sound" which (surprisingly) they prefer more.
Hi Michael or space2000,
I think what your after for, is an amp with a good sound reproduction with clarity on mid and highs, and a good tight bass on LF. In my opinion, you need both amps class A and class AB. A simple solution is to bi-amp them, class A on mid and highs and AB on LF with higher wattage. That should give you that satisfaction your looking for. Its a little bit of expensive but it's worth it. I think it would be impossible to attain those sonic quality that you want on just a single amplifier.
I think what your after for, is an amp with a good sound reproduction with clarity on mid and highs, and a good tight bass on LF. In my opinion, you need both amps class A and class AB. A simple solution is to bi-amp them, class A on mid and highs and AB on LF with higher wattage. That should give you that satisfaction your looking for. Its a little bit of expensive but it's worth it. I think it would be impossible to attain those sonic quality that you want on just a single amplifier.
lumanauw said:
I would call it sharp or bright treble. It can look as extra detail but in fact is not detail as you are hearing things that aren't on the record, it's distortion. My experience tells that this makes amps ready to be shown "hey, look at how good does this sound" as long as you know it won't be listened long enough for the listener to realize about the fatigue that this sound produces. A bad thing to have if you plan long listening sessions!
This is going to run and run isn't it. Theres more to it than just which Class it runs in. The single biggest diference ( audible improvement) I have found with solid state was to go back to using a single ended input stage which produces mainly even harmonic distortion, and distortion that rises at a much lower rate per octave than the LTP input stage.
Ionomolo sums it up quite well. Theres a world of difference between good Hifi and something that can really make music.
Ionomolo sums it up quite well. Theres a world of difference between good Hifi and something that can really make music.
Michael,
first thing you'd have to ask is what your current LSP wants.
The single-ended Aleph designs do not match well with a great many LSP systems, the main reason why so many build the bulky Class A bricks is because it is all so easy.
A lot of the Aleph type amp assemblers will have LSPs which are a total mismatch for single-ended Class A power amps, but are still pleased with the result because at modest levels it sounds so much better than the $*00.- integrated they replace.
At high SPL reproduction, likely the majority would all-in-all prefer a solid Class AB power amp on their LSPs than the Alephs.
A great many of the AL-3 to AL-5 hackers would find the early 90s Aleph designs a great deal more rewarding in combination with the loudspeaker system they have, the Push-Pull operation of the first Alephs enables solid bass reproduction of LSPs with lower sensitivity and less smooth impedance behaviour.
But nobody fancies to put their money on an old horse at the race track.
And a great many others would still find the PP-Alephs a compromise, you either love it or hate it, the Alephs have been marked with an acquired taste label since the start ~15 years ago.
On top of that, some have a preference for even (2nd) harmonic distortion while others for uneven (3d), some dislike high negative feedback numbers, some may crave for high volume levels while others are sensitive to higher distortion levels.
Even for the top level LSP system range, some prefer high wattage Class AB power amps while other Mega-Buck-LSP owners desire amps with at least 25W of Class A before diving into AB.
Like cars : some hate biggies, others are just not small enough to squeeze themselves in or out of most Italian tuna cans.
(tell you the truth, i dislike any labyrinth type LSP and most dynamic systems, on my main LSP system the lower power range SE Alephs are crab and the high dissipation level of an Aleph-2 just isn't worth it)
first thing you'd have to ask is what your current LSP wants.
The single-ended Aleph designs do not match well with a great many LSP systems, the main reason why so many build the bulky Class A bricks is because it is all so easy.
A lot of the Aleph type amp assemblers will have LSPs which are a total mismatch for single-ended Class A power amps, but are still pleased with the result because at modest levels it sounds so much better than the $*00.- integrated they replace.
At high SPL reproduction, likely the majority would all-in-all prefer a solid Class AB power amp on their LSPs than the Alephs.
A great many of the AL-3 to AL-5 hackers would find the early 90s Aleph designs a great deal more rewarding in combination with the loudspeaker system they have, the Push-Pull operation of the first Alephs enables solid bass reproduction of LSPs with lower sensitivity and less smooth impedance behaviour.
But nobody fancies to put their money on an old horse at the race track.
And a great many others would still find the PP-Alephs a compromise, you either love it or hate it, the Alephs have been marked with an acquired taste label since the start ~15 years ago.
On top of that, some have a preference for even (2nd) harmonic distortion while others for uneven (3d), some dislike high negative feedback numbers, some may crave for high volume levels while others are sensitive to higher distortion levels.
Even for the top level LSP system range, some prefer high wattage Class AB power amps while other Mega-Buck-LSP owners desire amps with at least 25W of Class A before diving into AB.
Like cars : some hate biggies, others are just not small enough to squeeze themselves in or out of most Italian tuna cans.
(tell you the truth, i dislike any labyrinth type LSP and most dynamic systems, on my main LSP system the lower power range SE Alephs are crab and the high dissipation level of an Aleph-2 just isn't worth it)
This sounds very familiar. Almost identical to Doug Self's definition of "his" ClassB.roender said:
Doug Self's ClassB = optimal bias ClassAB for the rest of us.
Set output Vre in the range 15mV to 25mV for all operating conditions. Doug uses 21.3mV to 27.4mVre for the normal range of Re values.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.