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Connected again for a fourth try at producing music. It lights up, but no sound.

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Buttoned up again for a trip back to China.

I'll report again when the replacement arrives. I fully expect it to operate.

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Neil,

You may want to mention that there is an empty spot on your PCB next to the blue Rubycon electrolytic power tank cap. On my SA-S1, there is a blue box-shaped cap that populates that spot. I'm not at home where I can tell you the exact value of this cap. There are a couple other smaller blue box caps in the output filter network next to the speaker binding post connections a that are also missing. Again, there are two empty spots there. I checked a photo of my T-amp that I had taken some time ago and noticed this anomaly. I'm sorry, but I cannot recall how to post photos on this forum for you to see exactly what I am pointing out, but you may want to bring this up to SMSL.

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Rich-

That's a great catch. I should have noticed those 4 empty spots, especially in comparison to the photo in the eBay listing. I've attached an annotated photo as a pdf showing 4 empty spaces. An annotated photo from SMSL's eBay listing wil be attached as a pdf to the next post.

I'll definitely bring this to the attention of SMSL-China, although the tracking indicates they already shipped a replacement.

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A photo (attached as a pdf) taken from SMSL's eBay listing clearly shows 4 blue components where empty spaces exist on the board in the amp they sent to me (shown in the pdf attached to the post above).

I'm eager to get their reaction to your sleuthing, Rich.

Thanks.

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To get around the need to click on the pdfs, I've taken a photo of the 2 pdfs and attached it to this post.

I also sent it to SMSL-China.

Your discovery, Rich, might explain why I received no folksy reply to the email I sent yesterday with the same photos. If 4 components were missing, as they appear to be, SMSL-China was probably embarrassed by seeing that and at a loss to reply.

I might be naive (no, I am naive) but I feel they are sincere about resolving the problem, embarrassed, but sincere.

I genuinely believe they'll send a fully functioning amp . . . . eventually.

After re-reading Rich's post above, it's clear a fifth component is missing. Another component is missing near the power switch and the blue Rubycon cap.

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The photos sent to SMSL-China prompted a further exchange of emails. The Sales Department expressed frustration with the Engineering Department for making "minor" engineering changes without alerting Sales. They asked if I could again send photos.

I next heard that Engineering explained the 4 missing parts are "auxiliary" resistors for "aesthetic" purposes only.

I replied with photos of the amp shown on their site. The four "1n5J 630- EVOX PFR" components between the output and input terminals (they're the small blue components in the upper left with writing on them) are absent in my amp.

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The "27nJ630" (missing from my amp) must have been the deal breaker.

I advised SMSL-China their Engineering Department is blowing smoke at them and at me. Why would adding or subtracting 4 "auxiliary" resistors affect the "aesthetics" of the amp when they should never be seen by the customer. More important, my amp was missing 5 components. Most important, IT DOES NOT WORK.

The ability of an amp to produce sound is not "auxiliary" or a matter of aesthetics," it's a necessity.

My amp and the one shown on the site indicate, "VER: 05." I must have gotten version 06. [;)]

Despite everything, I'm still confident they'll make it right.

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May I add another SMSL contender? Their SA-50 is by far the most musical chip amp I have ever owned. The tweaks mentioned above referring to the Lepai apply here as well (partly at least): better two input caps, new coils and better caps after the chip - we are talking here about 4-6 caps. Like this the amp I find in no way inferior to my rebuild MC30s.

Wolfram

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Wolfram-

Thanks for the input.

As it stands now, SMSL has shipped a replacement SA-S1. I must say, the response from SMSL has been immediate and phenomenal. Whoever I have exchanged emails with seems sincerely mortified and eager to do the right thing. He/she said SMSL would stop selling the SA-S1 until issues are resolved. I'm still confident they'll make it right. I hope the replacement works.

Before your recommendation of the SA-50, I was looking at some other SMSL amps. If the resolution goes as promised and expected, I might try another SMSL amp.

While, based upon my experience, I would encourage others to deal with SMSL, I would discourage purchasing the SA-S1 at this time.

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To their credit, SMSL-China has advised waiting to purchase any of their amps. They go on vacation next week (wasn't it just Chinese New Year?). When they return, they will revisit changes made to several amps.

By then, the replacement SA-S1 will have arrived. I'll post the verdict when the replacement arrives and when they give the green light to purchase again.

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The replacement arrived today. It looks good and works well.

After a brief listen, it sounds good. It seems better than the Lepai amps.

I notified SMSL-China of the arrival of the replacement amp. They might still be "conducting vacation" this week. When they give me the OK, I'll break the seal, open the case and photograph the insides to compare to the defective amp and the photos in the eBay listing.

I'm also waiting for the OK to purchase an SA-50.

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After some extended listening, I'm more impressed. The bass is better than the Lepai amps, and the highs are not strident like the Lepai amps.

This amp also lacks the off/on thumps of the Lepai amps. Even with it plugged into the switched outlet on the Dynaco FM-5, and turning it off without lowering the volume control on the amp, there is just the smallest "tick" from the speakers at turn-off.

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Glad to hear that SMSL sent you a working unit. Give it more time to break in and you'll really be treated to a fine sounding amp.

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And most of these chip amps can be made to sound even better if one carefully implements different parts. In my SA-50 I use new coils, different input caps and all the caps between chip out and speaker terminals. It took me some time to find the 'correct' parts (in terms of tonality), but I am pretty happy with the amp right now. Oh, and removing the volume pot didn't do any harm either....[:D].

Wolfram

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And most of these chip amps can be made to sound even better if one carefully implements different parts. In my SA-50 I use new coils, different input caps and all the caps between chip out and speaker terminals. It took me some time to find the 'correct' parts (in terms of tonality), but I am pretty happy with the amp right now. Oh, and removing the volume pot didn't do any harm either....Big Smile.

Wolfram

Can you share what specific changes and parts you installed in your amp to improve the sound quality? I found an interesting Web page on modifying STM chip-based amplifiers:

http://www.trevormarshall.com/class-d-tutorial/

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I continue to enjoy the sound of the replacement amp. SMSL-China's service is beyond reproach.

In the photos attached to this post and the posts that follow, the defective amp is #1 on the left; the replacement amp is #2 on the right. The new amp looks like #1, they do not look like the photos in the eBay listing (see pdf attached several posts back). It's missing the same 4 resistors between the input and output terminals and the air core inductors as #1. It's also missing the larger blue resistor near the power switch and the Rubycon can cap shown in the photos in the eBay listing.

While it sounds fine, I must admit I'd feel more comfortable without the blank spaces on the board. It would be more reassuring if it looked like the amp shown in the eBay listing.

SMSL-China should understand the market for these amps is do it yourself (DIY) audio hobbyists. Most will open their amps and be unpleasantly surprised if they lack parts shown in the eBay listings.

I welcome explanations from those more knowledgeable regarding chip amps than yours truly (which excludes almost no one) about the missing parts and the effect that has on performance.

I'm also interested in suggestions and guidance regarding modifications to this and/or the Lepai TA2020.

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