|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
94.111.40.237
Some of you might remember that I'm active bi-amping my horns with some tiny class D amps.
On the high pass (400 > 20KHz) I have a 8watt Trends TA10.1 highly modded; on the low pass (60 > 400Hz I have a stock SMSL SA50 (25W). Subs are driven by higher power class AB amp.
Well, I've very recently bought an upgraded, low noise, "audio" SMPS supply for my Trends amp.
The PSU is sold by the British company Amptastic, who makes the Mini1 amp. Both the Mini1 and my Trends amp share the same Tripath chip, and compatibility shouldn't be an issue even tho the upgraded PSU outputs 13.5V 7.5A and the stock one outputs 12V 3A.
And indeed, when using the Amptastic psu the sound is more organic and composed, less "in your face", and much less "class D".
HOWEVER, when using it, there's a faint high pitched noise coming from the horns, it's not like hiss, it's more like a faint tonality. It modulates if I touch the umbilical cable that links the PSU to the amp.
I contacted Amptastic who told me that failures where extremely rare and that I was probably experiencing some feedback.
But, what causes it? how can I prevent it? how come I don't experience it with the stock PSU?... I'm a bit lost here. It wasn't an expensive upgrade, of course, so it's not really a big deal financially, BUT besides that faint noise (which is very irritating through horns), it sounded great and I'd like to use it.
Any help welcome! :-)
Follow Ups:
I see, I almost destroyed my Trends, with would be a shame regarding all the mods it boasts. :-(I stupidly assumed the Amptastic amp and the mini1 were using the same chip, but it turns out the Amptastic uses TA2020 not TA2024... :-/ I hope nothing has been damaged (seems to work fine with the stock PSU)
I did ask to the Amptastic crew if I could use it with my Trends amp but ok, arguably I should have done my job better and searched for myself.
Now all I have to do is get rid of that PSU or buy the matching amp (one never has too many tiny amps, me thinks)
does anybody know of a good PSU to use with the Trends? SMPS would be great, but can be linear too.
Thanks everyone for your insight!
Edits: 09/02/20
you may have that reversed ... but both need the same juice
look on parts express etc. for turn key solutions
relax, play tunes ... I've noticed over the years the more I tweak
the more I'm compensating for hearing loss ... always fund the playback
that's you!
well, me anyway
best regards,
The increased rating of the PS amperage capacity from 3.5A to 7.5A would have nothing to do with hurting something because of too much current. The PS gives the amount of current it is asked to give. The increase in voltage of 1.5V, 12.5% could possibly cause a problem with too much current. I would look at the voltage rating of the chip that is said to be at risk. I would also measure the voltage coming out of the power supplys to see what the actual voltage is . EDIT: If it's the TA2024 chip then it looks like rivervalleys point is or could be correct. The max PS voltage is 13.2V.
"Two things are infinite: the universe and human stupidity; and I'm not sure about the universe." Alfred E. Neuman
Edits: 08/31/20
I bricked two of them running a 13.5V linear supply ... same symptoms the OP reports before failure
that's the TA2020 'Tripath' chip in there, 12V is spec & seems to be the upper limit ... higher amperage is a good thing though
regards,
When you say high amperage is a good thing what is it that you mean? Obviously the high voltage is not a good thing for this chip. Personally I agree that a higher amperage capacity PS should be intrinsically better sounding because of the parts differences... as long as the voltage is correct, which it is not in this case. Good of you to point this out to the OP. He needs a different PS if the voltage is over 13.2V.
"Two things are infinite: the universe and human stupidity; and I'm not sure about the universe." Alfred E. Neuman
higher capacitance makes for a 'stiffer' power supply ... more current reserve across the charge / discharge cycle
regards,
Higher capacitance, I'm all for it up to a safe point. I have been crucified in the past for suggesting that higher capacitance is a good thing sound wise.
"Two things are infinite: the universe and human stupidity; and I'm not sure about the universe." Alfred E. Neuman
that amp chip is sensitive to voltage and 13.5V is too much
the 'upgraded' PSU sounds better because of higher amperage
but it has been my experience that it will damage the amp eventually
it's likely that you're hearing the 'carrier waveform' being reflected
I've burned out two doing exactly what you're doing
with regards,
Having read that this problem can be cause by electromagnetic radiation it might be a good idea to try a ferrite core or two.
"Two things are infinite: the universe and human stupidity; and I'm not sure about the universe." Alfred E. Neuman
FAQ |
Post a Message! |
Forgot Password? |
|
||||||||||||||
|
This post is made possible by the generous support of people like you and our sponsors: