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Old 22nd February 2014, 11:00 PM   #51
mach1 is offline mach1  Australia
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Quote:
. New Year Special Offer:
APPJ PA0901A amp + Gold Lion (Genalex) Re-issue ECC83(Made in Russia) + Shuguang EL84 =USD190 + shipping cost
Black and Silver colors are available.

*** The special offer is valid until 31st, Jan., 2014.
Do you have any of these left?
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Old 26th February 2014, 04:07 PM   #52
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Hello,

Yes, only one set left.

Thanks,
Tony.
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Do you have any of these left?
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Old 22nd March 2014, 09:26 PM   #53
0mr is offline 0mr  Romania
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Default about components

Hello,
Can anybody tell me please if the received product appj is like the initial released version miniwatt n3? I'm talking about the pcb quality and components. The capacitors used are from nichicon and rifa? Who is the manufacturer of the output transformers? Thank you and best wishes!
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Old 25th March 2014, 04:52 PM   #54
0mr is offline 0mr  Romania
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Originally Posted by Musik007 View Post
Hello,

Yes, only one set left.

Thanks,
Tony.
Hello,

Is it still available?
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Old 6th April 2014, 07:59 AM   #55
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Originally Posted by 0mr View Post
Hello,
Can anybody tell me please if the received product appj is like the initial released version miniwatt n3? I'm talking about the pcb quality and components. The capacitors used are from nichicon and rifa? Who is the manufacturer of the output transformers? Thank you and best wishes!
Yes, the capacitors are "from" Nichicon and Rifa. This is what they are branded as, but are actually fakes. They still do their job, though.

My amp died. Symptoms were: tubes didn't light up, but the power supply light did. No sound, obviously. The cause: The primary psu capacitor (270F/400V) had ever-so-slightly swelled up and lost its ability to hold a charge. After replacement, the amp worked as new again.

It would seem that others have had this same problem. I suggest everyone replace this capacitor asap instead of waiting for it to die. The type is snap-in, 10mm pitch, dimensions are 25 mm diameter, 40 mm lenght. There is absolutely no space for bigger caps, and the value in question may be hard to find at this size. I went with 100F/400V instead, which has worked perfectly. The original capacitor, given its shoddy quality, could probably never actually store 270F.
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Old 8th April 2014, 10:58 PM   #56
0mr is offline 0mr  Romania
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Thank you for your answer. Are you sure that the caps are fake????? I didn't even know that chinese would make fake discrete components of well known brands. Nichicon are not even so expensive. I just had a doubt that they use rifa and nichicon in mass production at that price point, as advertised and in pictures. I also heared that the potentiometer is a mess, even if it's alps. I'm thinking to buy one and change all the caps and potentiometer. If there is no space for a bigger cap i can fit one outside the case. I also want to use a socket saver to protect the board and the smd res/caps that are around the sockets from excessive heat.
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Old 11th April 2014, 07:19 PM   #57
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Are you kidding? Every single component from any sort or reputable brand is being faked these days. Nichicon in particular has had a counterfeit warning on the front page of their website for years.

While trying to figure out the faults in this, I compared all the components in this amp to real parts from the various manufacturers and they all looked suspicious and not the same quality as the real thing. The easiest way to tell is usually the printing, which can be faded, off-center, wrong font, etc. Also sizes and even shapes differ.

The amp is really brilliant, and there is no need to modify it. Out of the box, it's the best amp I've ever used. And I've used quite a few. Properly sized caps are widely available and fitting one outside of the chassis will be greatly detrimental to the functionality of the circuit. You may even render it unusable. It uses an SMPS and you don't screw around with those.

There's nothing wrong with the potentiometer. It does its job well. It may be somewhat uneven at the start, but that's normal and usually not a big deal (it takes a LOT of unevenness between channels to be audible). A different potentiometer will definitely not fit in here, and resorting to bypassing it and instead using an external pre-amp is criminal - aesthetically speaking. This tiny amp works really well on its own, and the main reason for its appeal is its way of making uglier, bigger stereo systems a thing of the past.

The thing runs hot, but it's a tube amp - that's normal. The SMD components are in no danger here. The only thing that needs sorting out are the electrolytic capacitors. I've put hundreds of hours into this thing, and it has shown no sign of dying (apart from literally dying... but that was just once! Knock on wood.).

If you want DIY, I recommend looking elsewhere. This is not an amp for basement dwelling Frankenstein creators, it's more of a WAF-optimized thing: it even comes in pink! (ps: which I deeply regret not getting.)
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Old 12th April 2014, 06:15 PM   #58
0mr is offline 0mr  Romania
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Thank you for the information! I asked about the Nichicon because it doesn't worth to manufacture a fake cap if the original one costs about 20-50 cents. It like manufacturing fake Q&Q low cost watches instead of a 10-50k watch.
About the SMPS i was thinking to bypass it and put a real PS outside the chassis .
I think i'll buy one and just change the caps. I'll also buy a pair of Pioneer SB-B22. I'd rather buy full range speakers but i couldn't find a pair for 150-200$.
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