well, im obviously new here. but this seems to be the best place to ask questions about the t-amp.
i just ordered myself one and it came in the mail yesterday. i played it for maybe 10 mins then. today i played on it for an hour or less and i noticed a crackle/hiss in the left channel. its always when the song hits alot of treble to. the mids aren't affected.
im running off of a Wall Wart(12V, 1A) and my speakers are from my stereo(sony, 6 ohm)
i know its the left channel and not my speaker because i've switched them around and its always the one plugged into the left channel, a very annoying hiss/crackle.
help please. i would very much like to enjoy the same thing that everyone else has enjoyed with this little amp. but my first experiences with it have been crappy.
i just ordered myself one and it came in the mail yesterday. i played it for maybe 10 mins then. today i played on it for an hour or less and i noticed a crackle/hiss in the left channel. its always when the song hits alot of treble to. the mids aren't affected.
im running off of a Wall Wart(12V, 1A) and my speakers are from my stereo(sony, 6 ohm)
i know its the left channel and not my speaker because i've switched them around and its always the one plugged into the left channel, a very annoying hiss/crackle.
help please. i would very much like to enjoy the same thing that everyone else has enjoyed with this little amp. but my first experiences with it have been crappy.
Hi, I'm facing a similar problem with my T-Amp.
In my case I'm pretty sure both channels hiss, and there's also a noticeable "humm" in the middle third of the volume scale. It disappears below 1/3 and above 2/3s volume. But the hiss stays, and it's specially loud from the tweeters (as expected).
I'm blaming it on my power supply - it's a 12V 2A switch mode thing that looks like a Nokia mobile phone charger. It plugs into the wall, so I'm guessing it's a "wallwart" too (though I'm not familiar with the term).
Are you using a switched or linear PSU? You can tell by the wheight of the thing.
I've been searching for a definitive answer to the "correct power supply for a T-Amp" question. So far, unsuccessfully. Some folks swear by SMPS, others say linear is the way to go. It seems that switched mode supplies tend to add a fair bit of noise that is combined with the amp's own noise (since it's sort of a switched mode PS for the speakers after all).
The hummmmmmm that only appears within a certain volume range seems to be a different challenge altogether. I'll try yet another linear supply later today or early tomorrow and will report back here.
Also, there seems to be a noise problem with some T-Amp units. Maybe you should look into that too.
Keep us posted, we want our T-Amps to rock!
Cheers,
Livino
In my case I'm pretty sure both channels hiss, and there's also a noticeable "humm" in the middle third of the volume scale. It disappears below 1/3 and above 2/3s volume. But the hiss stays, and it's specially loud from the tweeters (as expected).
I'm blaming it on my power supply - it's a 12V 2A switch mode thing that looks like a Nokia mobile phone charger. It plugs into the wall, so I'm guessing it's a "wallwart" too (though I'm not familiar with the term).
Are you using a switched or linear PSU? You can tell by the wheight of the thing.
I've been searching for a definitive answer to the "correct power supply for a T-Amp" question. So far, unsuccessfully. Some folks swear by SMPS, others say linear is the way to go. It seems that switched mode supplies tend to add a fair bit of noise that is combined with the amp's own noise (since it's sort of a switched mode PS for the speakers after all).
The hummmmmmm that only appears within a certain volume range seems to be a different challenge altogether. I'll try yet another linear supply later today or early tomorrow and will report back here.
Also, there seems to be a noise problem with some T-Amp units. Maybe you should look into that too.
Keep us posted, we want our T-Amps to rock!
Cheers,
Livino
thanks man !
as far as the power supply goes. im not to keen on all the different kinds. all i know is its your basic AC to DC supply, like the ones you see for almost any electronic appliance around the house.
i have a friend who's a major audiophile and i will let him check it out. hopefully he can help me also(and you to)
but thank you for keeping me posted on this ! i hope we can figure out this problem
as far as the power supply goes. im not to keen on all the different kinds. all i know is its your basic AC to DC supply, like the ones you see for almost any electronic appliance around the house.
i have a friend who's a major audiophile and i will let him check it out. hopefully he can help me also(and you to)
but thank you for keeping me posted on this ! i hope we can figure out this problem
Nehpets - Are you certain that the problem isn't elsewhere in your system? I made some mods to a class-T amp this week and when I powered it up again, I had a hiss. I spent a few hours checking over the amp, only to find out that it was a bad connection from my DAC! 
Livino - Don't waste your time looking for definitive answers on these forums. 😀 But take my word for it, SMPS is the way to go. 😉
Livino - Don't waste your time looking for definitive answers on these forums. 😀 But take my word for it, SMPS is the way to go. 😉
I'd just like to reply that I'm also experiencing these problems with my t-amp hooked up to my computers psu. I'm thinkin about getting an SLA to see if it helps things out. I hope we can get a definitive answer to what makes and models of power supplies people are using with good results.
I found a company in my city that specializes in custom-made power supplies. I've ordered a 13V 1.25A linear PS from them which I'm picking up today.
Custom-made stuff is kind of expensive as you can imagine, so cost ruled out a 2A supply. The 1.25A box is plenty expensive already at about $55 - $15 more than what the T-Amp cost me with postage to Brazil included...
Anyway I'll post my impressions later today. 🙂
Custom-made stuff is kind of expensive as you can imagine, so cost ruled out a 2A supply. The 1.25A box is plenty expensive already at about $55 - $15 more than what the T-Amp cost me with postage to Brazil included...
Anyway I'll post my impressions later today. 🙂
UPDATE
Ok, I just got the new custom-made supply. I didn't have that much time to test it during my lunch break, but at least it didn't hum or hiss or anything. Good sign...
Well, there is a very, very faint hiss from the tweeters if I crank the volume up all the way. The hum in the middle 1/3rd of the volume scale was initially there but disappeared completely after I accidentally switched the power supply off and on again a couple of times (the connector was a bit loose, it's fixed now).
I nicked a 12V 1.25A switch-mode PS from my brother's Cannon scanner to compare sound quality later today. Good thing that they have identical output specs, too bad I didn't notice the Canon PSU earlier or I might have saved the money spend on the Nokia-looking thingy. But the linear PSU is looking promising!
I'll keep you guys posted on my testing, but so far the linear box is a clear winner.
Ok, I just got the new custom-made supply. I didn't have that much time to test it during my lunch break, but at least it didn't hum or hiss or anything. Good sign...
Well, there is a very, very faint hiss from the tweeters if I crank the volume up all the way. The hum in the middle 1/3rd of the volume scale was initially there but disappeared completely after I accidentally switched the power supply off and on again a couple of times (the connector was a bit loose, it's fixed now).
I nicked a 12V 1.25A switch-mode PS from my brother's Cannon scanner to compare sound quality later today. Good thing that they have identical output specs, too bad I didn't notice the Canon PSU earlier or I might have saved the money spend on the Nokia-looking thingy. But the linear PSU is looking promising!
I'll keep you guys posted on my testing, but so far the linear box is a clear winner.
Nuuk - interesting that you are recommending a SMPS. I started another thread trying to get some guidance on the right kind of psu to use with the AudioDigit t2020-m. So far plenty of views but no answers!
Anyway as I say interesting that you are saying SMPS, the autocontruire site says get a linear 11-13.5v 3-5A. Do you know anywhere one could source a readymade SMPS version with those specs in the UK?
Judging by appearances your a man that knows what he's talking about on these forums (but you know what they say about judging by appearances...😉
Anyway as I say interesting that you are saying SMPS, the autocontruire site says get a linear 11-13.5v 3-5A. Do you know anywhere one could source a readymade SMPS version with those specs in the UK?
Judging by appearances your a man that knows what he's talking about on these forums (but you know what they say about judging by appearances...😉
Yes, be warned, I know very little!
I tried a wallwart, a home-built regulated linear supply, SLA battery, and one of those SMPS modules and I can honestly say that the SMPS was clearly the best sounding supply. If Leo is watching this thread, he will confirm what I say.
The ones on DD are ready built. All you have to do is wire them up and add a loading resistor to the 5 volt output. You can buy similar modules all over the place (for a lot more) but I don't know of any completely finished examples (ie with cases, switches and sockets).
I hope to be able to offer a finished version of the SMPS in a rather smart casing in the not too distant future! 😉
I've tried a few different diy PSU's, regulators etc for my Amp3
I also used 12v 7aH batteries with and without 10k caps on the output.
NUUKs SMPS was the last I tried and to be honest it easily gave the best results
Fit a good 10'000uf cap on the output😉 the music just sounds more right
I've had very good results with the SMPS powering other parts of my Hi-Fi too
I also used 12v 7aH batteries with and without 10k caps on the output.
NUUKs SMPS was the last I tried and to be honest it easily gave the best results
Fit a good 10'000uf cap on the output😉 the music just sounds more right
I've had very good results with the SMPS powering other parts of my Hi-Fi too
T, Nuuk, - thanks guys, I am sold. I appreciate you sharing your knowledge and experience.
Nuuk I will email you regarding a purchase. Don't want to clutter up these fine forums with vulgar commerce.
Can you just tell me - what kind of limitations am I placing on the Amp using the puny 12V 500mA supply? Just for my general knowledge i.e. what does a more powerful PSU do sonically.
Nuuk I will email you regarding a purchase. Don't want to clutter up these fine forums with vulgar commerce.
Can you just tell me - what kind of limitations am I placing on the Amp using the puny 12V 500mA supply? Just for my general knowledge i.e. what does a more powerful PSU do sonically.
No probs Joe
You should have fun comparing the SMPS to the wall wart.
All the other supplies I tried would be better than a Wall wart so you should hear more than a noticeable improvement😉
What limititations would you have with 500mA , probably bass and control😀 Class-T are efficient but 500mA would soon run out of juice
I think the SMPS are around 6A for the 12v so is more than enough.
Its not just the higher current but SMPS seem to work very well with these amps anyway
You should have fun comparing the SMPS to the wall wart.
All the other supplies I tried would be better than a Wall wart so you should hear more than a noticeable improvement😉
What limititations would you have with 500mA , probably bass and control😀 Class-T are efficient but 500mA would soon run out of juice
I think the SMPS are around 6A for the 12v so is more than enough.
Its not just the higher current but SMPS seem to work very well with these amps anyway
T, excellent I can't wait. The little AudioDigit amp is a remarkable improvement - so much more detail and clarity there. Its also much more dynamic than what I was using previously. However it does very quickly run out of juice. Better bass and control sounds just what the doctor ordered.
I emailed Nuuk and am going with the SMPS that you and he recommend. Will be trying your Cap tip also. I'm looking forward to the comparison.
I emailed Nuuk and am going with the SMPS that you and he recommend. Will be trying your Cap tip also. I'm looking forward to the comparison.
im begining to think its not my power supply.
ive taken everything out of the plastic case. so i basically have a Pot and Board sitting on my floor.
ive used batteries a 12V 500 MilliAmp power supply(wallWart). a 1000 MilliAmp(also wallWart), and am old computer power supply thats 12V with up to 5Amps.
still fuzz in the left channel.
so i snipped the Cap in the left channel thinking my cap was bad. no change.
i snipped the one in the right channel just to see if it would even change the sound in a correctly working channel. no change there either. soooo
im begining to think its either A. a bad chip. or B. im still not using the right power supply. but im coming to the conclusion that it may not be power...
could someone please help me ? i will look into the power supplies everyone here has recommended. but i don't wanna spend the money on something that won't fix my problem...
ive taken everything out of the plastic case. so i basically have a Pot and Board sitting on my floor.
ive used batteries a 12V 500 MilliAmp power supply(wallWart). a 1000 MilliAmp(also wallWart), and am old computer power supply thats 12V with up to 5Amps.
still fuzz in the left channel.
so i snipped the Cap in the left channel thinking my cap was bad. no change.
i snipped the one in the right channel just to see if it would even change the sound in a correctly working channel. no change there either. soooo
im begining to think its either A. a bad chip. or B. im still not using the right power supply. but im coming to the conclusion that it may not be power...
could someone please help me ? i will look into the power supplies everyone here has recommended. but i don't wanna spend the money on something that won't fix my problem...
Yes, first swap the speakers and source around just to make sure it is the amp with the bad left channel.
I noticed my Amp3 would distort through my ribbon tweeters only if I pushed it too hard but it would do this with both channels.
Ideally you could do with a sig gen and scope to check the outputs.
Normally if the chip is faulty it would shut down, are the inductors on the output ok?
I noticed my Amp3 would distort through my ribbon tweeters only if I pushed it too hard but it would do this with both channels.
Ideally you could do with a sig gen and scope to check the outputs.
Normally if the chip is faulty it would shut down, are the inductors on the output ok?
i don't know what the problem is.+ i've tried checking all my connections. re-soldering power/inputs. nothing seems to make the hiss go away. sould it be a bad Cap ? if not i may just have to buy another one. either way im stupid as far as audio electronics goes so most of the things you guys are saying make no sense to me anyways.
noisy amp problem
Don't overlook the possibility it could very easily just be a bad chip. If this is a SI unit, don't even try to replace it as the PCB will never survive. If it is an amp3 it could be done very carefully if you could get a replacement chip.
I would want someone with a scope to check it out before I went to all this trouble. It could be a bad bypass cap or bad connection somewhere just as easily and these should show up with a scope.
Roger
Don't overlook the possibility it could very easily just be a bad chip. If this is a SI unit, don't even try to replace it as the PCB will never survive. If it is an amp3 it could be done very carefully if you could get a replacement chip.
I would want someone with a scope to check it out before I went to all this trouble. It could be a bad bypass cap or bad connection somewhere just as easily and these should show up with a scope.
Roger
Hey guys,
You guys mentioned that a SMPS with a 10k Cap gives best results. I'm going to be building an amp3 when it comes.
So what about using a laptop based (brick) SMPS? Is it important that the skynet PS is used or can it be any decent quality SMPS? I don't like the idea of putting a resistor on the 5 volt output just to keep it happy. To me that just seems like wasting energy, and it gets hot. 
You guys mentioned that a SMPS with a 10k Cap gives best results. I'm going to be building an amp3 when it comes.
So what about using a laptop based (brick) SMPS? Is it important that the skynet PS is used or can it be any decent quality SMPS? I don't like the idea of putting a resistor on the 5 volt output just to keep it happy. To me that just seems like wasting energy, and it gets hot. - Status
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