I'm not suggesting the design isn't legitimate, just that the specs are overly optimistic. But that's fairly common in the audio world.
It certainly suggests it should be a reliable piece of equipment. But what does he know about achieving high quality sound from the design of medical power supplies I wonder?
He's been designing audio a long time, is an avid audio gear type, probably just like you. Give him a call if you really want to offer some comment.
This is interesting. If my amps had low performance in THD+N I'd not be trumpeting the fact. Or is there something of the hair shirt mentality coming in here - low performance in THD means its optimised for something other than linearity?
I'm sure its a typo
Where full power is 100W into 8R? I can't help but see the irony here - the reason it never gets hot at full power is because it thermally limits and effectively shuts down.
You're guessing here
More hype here - the min specified slew rate is 7V/uS for the chip, 10 is the typical figure. Are we to believe that he hand picks the chips for better than typical slew rate?
I don't know, do you?
A rather dismissive set of replies
I don't have a copy of IEC 60268-3 so maybe it allows short term output power to be put on the spec sheet. Anyone else know about this?
Hi Phil,
Abrax has read the specification and rightly draws his conclusions, much of which he says are exaggerated.
You have read the specification but literally accept everything printed but with no thought about how the numbers have been massaged to look better than achievable.
I would be more inclined to put more faith in Abrax's interpretation.
Go back and read the spec again and the datasheet and compare Abrax's comments to what is printed in those sheets.
Abrax has read the specification and rightly draws his conclusions, much of which he says are exaggerated.
You have read the specification but literally accept everything printed but with no thought about how the numbers have been massaged to look better than achievable.
I would be more inclined to put more faith in Abrax's interpretation.
Go back and read the spec again and the datasheet and compare Abrax's comments to what is printed in those sheets.
Can't think why I'd need to call him to repeat what I've already put in the public domain here.
Yep, but its an educated guess based not only on the manufacturer's datasheet but my own experience with the part in question. Your basis for supporting the claims is what?
Nope, but another educated guess suggests not - its consistent with some of his other claims (and potential typo) that this >10V/uS is an erroneous claim.
On the contrary, your replies are dismissive as they don't engage with the content of my arguments. Have you looked at the datasheet yourself? Have you seen ST Micro's own claims for the TDA7294 and compared them with the claims for this amp?
Only in reference to amplifier heating--- the lower the value of damping the less heat any amp seems to make. My amp has lots of feedback and very high damping. My first use of it on a sub with 100 square inches of heat sink was not even close to enough heat sink. It over heated right away. Further testing for the sub got me to the 300 square inches of heat sink value. This is for two of the chips (3886) running on 35 volts.
Yes in my circuit the slew rate of the composite amp was 1 volt per microsecond higher with the very same chip than the chip by itself. Nice surprise. Not the same number, the very same part.
Yes in my circuit the slew rate of the composite amp was 1 volt per microsecond higher with the very same chip than the chip by itself. Nice surprise. Not the same number, the very same part.
I apologize for being dismissive.
I do think that it is better to keep the analysis less judgmental tonally.
However, it appears that those here who are more qualified than I, may in fact be correct in their assumptions.
I still accept that the designer may be correct unless I can prove otherwise.
As always, I very much appreciate this forum.
We all make mistakes and I hope to get better at not making them.
Thanks
I do think that it is better to keep the analysis less judgmental tonally.
However, it appears that those here who are more qualified than I, may in fact be correct in their assumptions.
I still accept that the designer may be correct unless I can prove otherwise.
As always, I very much appreciate this forum.
We all make mistakes and I hope to get better at not making them.
Thanks
I think you're misinterpreting that line. They are saying "Low THD+N" and added the marketing word performance.
I agree with you, no judgement is better. But that's exactly the way I write - without judgement. Maybe because I write without judgement I'm more inclined to speak directly - that directness is what you interpret as being judgmental.
I hope to continue making mistakes myself as with no mistakes, there's no learning. So even though my style is to write directly, please do point out my errors - sure, we all make them.
I think you're misinterpreting that line. They are saying "Low THD+N" and added the marketing word performance.
Yep, I had thought of that way of looking at it and probably its what was in the writer's mind. But I decided to take the words at face value and have some fun with them
It is quite common when an amp is marketed as 'audiophile' as this one is that distortion is either not specified or is quite high as a way of suggesting 'we concentrated on the sound in this design, if the distortion suffered in the process then tough, that's the price of great sound!'Well I use a pair of LM3886 built to the standard NS circuit but good quality parts and very good earthing (it's DC coupled also) and I use this in preference to a Musical Fidelity A370 and Leak Stereo 20 valve amp. My 25WPC split rail supply JLH class A probably just beats it but some times I'm not so sure....
So yes they are pretty damn good by any standard.
So yes they are pretty damn good by any standard.
Of the three amps I find listenable around here my version of the 3886 comes in last by a nose. It is so close to number two I believe optimization of the 3886 may make it number two. The one I use was built with stock on hand and is not really optimum. On the other hand both #2 and #3 are some ways from the #1 amp. Also, #3 is still ahead of anything else tried in the marketplace... about 100 other "audiophile" amps and even some common stuff. As for common, the Insignia at Besty Bu is pretty darned good and very cheap. Please, this is just an opinion. Thanks.
so what is the cheapest consumer A/V $/W with hackable analog power chip amps?
my quick look shows a Sony STRDH740 - "7x145 W, @6 Ohm" for $300 msrp - of course they are playing games with the rating - 240 W rating for the mains power??
whats inside? can we parallel 3 of the channels per side for a OK stereo amp? parallel+bridge for (likely weedy) monoblock?
maybe look for more realistic rated lower power chip amp based A/V amp
Pioneer VSX-822-K 5x80W at least claims a 450 max line power - $230 from Walmart
my quick look shows a Sony STRDH740 - "7x145 W, @6 Ohm" for $300 msrp - of course they are playing games with the rating - 240 W rating for the mains power??
whats inside? can we parallel 3 of the channels per side for a OK stereo amp? parallel+bridge for (likely weedy) monoblock?
maybe look for more realistic rated lower power chip amp based A/V amp
Pioneer VSX-822-K 5x80W at least claims a 450 max line power - $230 from Walmart
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The TDA7293V came in years after I had done testing. Clearly, that one is the best sounding by quite a bit simply using the data sheet design. The very cool things are higher voltage and designed with the intent to run multiple chips in parallel for greater current. Have not implemented my specific design using this chip but is on the to do someday list.
As for higher power, I greatly prefer more channels and a single amp connected to every speaker instead of trying to make a powerful amp pull a huge train with all those losses.
As for higher power, I greatly prefer more channels and a single amp connected to every speaker instead of trying to make a powerful amp pull a huge train with all those losses.
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