Well, something else new and interesting from Rod Elliot. Just saw this today.
http://www.sound.westhost.com/project3b.htm
figured i'd give everyone a heads up :-D
-Matthew K. Olson
http://www.sound.westhost.com/project3b.htm
figured i'd give everyone a heads up :-D
-Matthew K. Olson
Doesn't look very unique...you are right. Input cap is smaller ...cheaper? and r9 and r10 are 3.3k instead of 2.2k emmiter resistors are .33 instead of .47ohms. Devices are slightly different, though I think that if another pair of output devices were added....you could just overbias the regular p3a to the same effect. Who knows. I'm really just talking out my rear end right now. Anyone else have an opinion?
-Matthew K. Olson
-Matthew K. Olson
Well...i got some big heatsinks....maybe I'll crank up the bias to like 3-5A haha. Too bad I don't even have a p3a done yet. Just gotta use a 1kva toroid per channel. No problem 
Actually, there is a problem...I keep throwing the breaker in my condo when I switch on my Holton monoblocks. 
later!
-Matthew K. Olson
Actually, there is a problem...I keep throwing the breaker in my condo when I switch on my Holton monoblocks. later!-Matthew K. Olson
Actually ....
I think it is fair to say that Rod isn't claiming some great breakthrough/change ..... just making it more user-friendly for building, PCBs etc.
Reminds me a little of an A40, but using discrete devices cf darlingtons .... couldn't pick on him for that ..... and I still quite like my A40
mark
I think it is fair to say that Rod isn't claiming some great breakthrough/change ..... just making it more user-friendly for building, PCBs etc.
Reminds me a little of an A40, but using discrete devices cf darlingtons .... couldn't pick on him for that ..... and I still quite like my A40
mark
No verdict ....
Didn't post a verdict.
Have never built or heard one of Rod's amps, nor do I know him in any way. I have noticed a "mild" undercurrent of disfavour though ..... I do wonder where this comes from
cheers
mark
PS: Would be interested to hear if anyone has built one and willing to give an objective review.
Didn't post a verdict.
Have never built or heard one of Rod's amps, nor do I know him in any way. I have noticed a "mild" undercurrent of disfavour though ..... I do wonder where this comes from
cheers
mark
PS: Would be interested to hear if anyone has built one and willing to give an objective review.
To Per
I'm surprised, that this told you, man who like unsimple and sophisticated circuity. This circuit was new thirty years ago and its distortion is for today too big. I never heard any Elliot's amps, but looking at schematic is enough for me, I have adequate experiences with amps and listening too .
I'm surprised, that this told you, man who like unsimple and sophisticated circuity. This circuit was new thirty years ago and its distortion is for today too big. I never heard any Elliot's amps, but looking at schematic is enough for me, I have adequate experiences with amps and listening too
.
Dunno....I've heard the P3A in several incarnations, and was impressed. Too lazy and too busy to do one myself.
He stands up there and takes pot-shots from all these Mon-morning Q-backs, yet precious few can come up with anything near as educational or aurally pleasing.
He does the DIY world a great service by publishing projects that can be tackled by nOObies, and for that he has my respect.
If you can judge how an amp will sound directly from it's schematic then you are more talented than me. I generally like to hear a piece of equipment before passing judgement.
I have built Rod's P3A and one of his headphone amp designs as well as Project 85 (the SPDIF DAC) which is on his site but not one of his designs. They are uniformly good, if not exellent and easy to build to boot. Rod's amps aren't the only good ones and aren't perfect, but I wouldn't hesistate to recommend one of his designs.
I have not heard the P3B (might build one this weekend though) but I would guess it would be as good as his other designs.
To cabbagerat
It's easy to estimate how this amp will have a sound : input transistors are BJT - in my experience much better sound have fets. VAS is simply and probably will have nonsymetricaly slew rate. Here is not any antisaturation circuit - by clipping amp will have problems, all stages will be highly saturated ( 25 W amp is easy to get to the limitation ). Voltage rails for input and VAS have the same filtration as output stage - probably problems with SNR. No " electronic fuse " and recomented fuse 3 A on rails is for this output power too big - if you do short on output, then blows, output devices will be on silicon heaven . This amp is still relatively good and probably easy to made and stabil, but I don't like simply solutions - I certainly realize, that somebody have opposite view.
It's easy to estimate how this amp will have a sound : input transistors are BJT - in my experience much better sound have fets. VAS is simply and probably will have nonsymetricaly slew rate. Here is not any antisaturation circuit - by clipping amp will have problems, all stages will be highly saturated ( 25 W amp is easy to get to the limitation ). Voltage rails for input and VAS have the same filtration as output stage - probably problems with SNR. No " electronic fuse " and recomented fuse 3 A on rails is for this output power too big - if you do short on output, then blows, output devices will be on silicon heaven
. This amp is still relatively good and probably easy to made and stabil, but I don't like simply solutions - I certainly realize, that somebody have opposite view.
Re: To Per
OK, some stuff is old, but tell me what is really new?
I gather that Rod had a certain goal here and that was few parts (= easy to build). My goals are totally different.
What about Hugh's and Pass' stuff if we talk distortion, bandwidth etc.?Upupa Epops said:I'm surprised, that this told you, man who like unsimple and sophisticated circuity. This circuit was new thirty years ago and its distortion is for today too big. I never heard any Elliot's amps, but looking at schematic is enough for me, I have adequate experiences with amps and listening too
OK, some stuff is old, but tell me what is really new?
I gather that Rod had a certain goal here and that was few parts (= easy to build). My goals are totally different.
Re: To Per
I can't be sure of course but I think there are people who think differently.
Upupa Epops said:I can't talk about Pass - for my ears all his product have unacceptable distortion and I mean, that " behind mask " he is giggle, 'cos he knows it too. What is new ? I mean, that you, same as I, are looking into datasheets of modern opamps and some patents, 'cos news are there
I can't be sure of course but I think there are people who think differently.
Everyone may be entitled to their own oppinion, but generaly it is far more sensible for the person giving that oppinion to actualy have some experience of what they are talking about. For example, I had never eaten haggis before sunday night (and the ingreedients in that "sound" truely disgusting, even down the sheep's stomach it is cooked in), but as I had never tasted it before I remained open minded about what it might be like (as surely people wouldn't make it if it was that bad). And; perhaps supprisingly, I was amazed to find that it tasted very nice (one of the few good things about Burn's night in fact).
So, perhaps here it would be fairer to at least try the thing you are proclaiming to know about before casting your judgement; as not all of your coments seem to make sense to me (especialy the coments about the circuit becoming saturated, as it is clearly pointed out that this is a lower power version of a proven design, so why should it have any trouble opperating at a lower power level?).
So, perhaps here it would be fairer to at least try the thing you are proclaiming to know about before casting your judgement; as not all of your coments seem to make sense to me (especialy the coments about the circuit becoming saturated, as it is clearly pointed out that this is a lower power version of a proven design, so why should it have any trouble opperating at a lower power level?).
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