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Old 7th May 2012, 09:48 AM   #1151
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Originally Posted by sofaspud View Post
It would surprise me if I was the only guy that replaced the op amps on his Lepai. The only serious issue I had was some stability problems (I don't even recall how exactly they manifested themselves) but they fixed themselves. And I find it did remove much of the harshness I could get out of the stock amp (it could become genuinely painful to listen to). I had some SMT LM833's handy and used those. Many satisfied listening hours later, I wouldn't hesitate to do it again.
I was thinking of doing the input capacitor mod and maybe the output inductors as those seem to be the most recommended and look relatively easy but I think small surface mounted chips will be beyond me.

Why do you think they have soldered extra components across the legs of the opamps on mine? I couldn't see these on the photos posted of the earlier version.
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Old 7th May 2012, 01:42 PM   #1152
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Why do you think they have soldered extra components across the legs of the opamps on mine?
I don't know for sure, but they've tweaked the feedback response of the op amp, maybe to improve the low end or "soften" the highs.
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Old 7th May 2012, 05:56 PM   #1153
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I am somewhat suspicious that power supply problems are causing some of the troubles described with the Lepai amps. I have 3 of these, and all 3 sound very good, into various (high efficiency) speakers, as well as headphones (rewired for 4 conductor connection).

The power supplies I have seen in on-line ads for the Lepai on E-bay look really cheesy. Parts Express charges more, but includes what I believe to be a better 12 V 2A supply. It is relatively easy to build a very good 12 VDC regulated supply (most standard 12V wall warts are either unregulated or poorly regulated). Results from the lower powered Tripath chips are VERY dependent on power supply quality, particularly regulation, for accurate reproduction of low frequencies, and also for keeping distortion low at moderate volume levels. I have done some experimenting with the TI TPA 3123 chip, and a well regulated linear PS makes a HUGE difference. A good SMPS (e.g. a 12V 150W Meanwell) would probably sound good also.
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Old 8th May 2012, 09:40 AM   #1154
blossom is offline blossom  New Zealand
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Originally Posted by stujonesmd View Post
Results from the lower powered Tripath chips are VERY dependent on power supply quality, particularly regulation, for accurate reproduction of low frequencies, and also for keeping distortion low at moderate volume levels. I have done some experimenting with the TI TPA 3123 chip, and a well regulated linear PS makes a HUGE difference. A good SMPS (e.g. a 12V 150W Meanwell) would probably sound good also.

What makes you use a 150W smps as an eg, should 60W not be sufficient for one of these chips?

Last edited by blossom; 8th May 2012 at 09:42 AM. Reason: to reword
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Old 8th May 2012, 09:46 AM   #1155
blossom is offline blossom  New Zealand
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ops double posted

Last edited by blossom; 8th May 2012 at 09:47 AM. Reason: double posted
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Old 8th May 2012, 01:02 PM   #1156
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Originally Posted by sofaspud View Post
I don't know for sure, but they've tweaked the feedback response of the op amp, maybe to improve the low end or "soften" the highs.
Or to try and avoid any high freq oscillations with all that RF flying around in close proximity.
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Old 10th May 2012, 09:35 AM   #1157
Franfj is offline Franfj  Spain
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Originally Posted by jumpingclear View Post
I was thinking of doing the input capacitor mod and maybe the output inductors as those seem to be the most recommended and look relatively easy but I think small surface mounted chips will be beyond me.
I would do the capacitor mod (both the electrolytic power capacitor, and MKP sound input capacitors change), is cheap, easy and provides a huge improvement in sound quality. But the inductor mod is more expensive and difficult to do, and personally I don't think that the difference worth the money.

Anyways, the components quality on Lepai amps, vary from one to another... if you have weak inductors probably you will notice the difference a lot, the same occurs with other components...
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Old 10th May 2012, 10:09 AM   #1158
jjne is offline jjne  United Kingdom
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Here's the thing though -- I also did the capacitor upgrade/tone bypass on my 2020B, and although the sound quality is now very good, there is a noticable roll-off in frequency response at the bass end. In simple terms -- the amp is now lean, and lacking in bass.

I have not upgraded the power capacitor, but I am unconvinced that that would make a substantial difference. I now find the amp displeasing to listen to, and am tempted to revert the changes and sell it on in all honesty.
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Old 10th May 2012, 10:31 AM   #1159
Franfj is offline Franfj  Spain
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If the leds dim when the bass kicks, you should do the power capacitor mod, if not, the problem is in other place…
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Old 10th May 2012, 08:32 PM   #1160
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I recently got a Lepai ta2020, paired it with some bs1000 Sony Bookshelfs and pretty impressed with the sound and power this little thing puts out.

However are you guys just leaving the case as is? I've been searching and trying to see if there were custom enclosures, metal, wood etc, or at least instructions to put one together but can't find anything as it's a bit ugly looking stock lol. Or even with the more powerful kits like amp6 .... are there any enclosures or anything? I've seen a few pics of ones made with copper etc but that seems way outta my league lol
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