My (very) mini review of the Singxer SU-1 DDC

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23 hours ago, T-Bone said:

When you're on a conference call, no one knows your disassembling an SU-1!  

 

Here's a few pix of my S1117 installation.  I'll apologize in advance for 2 things:  

(1) Crappy iPhone picture quality

(2) The fuzzy lint in some of the pix is from a cotton patch that I soaked with rubbing alcohol to remove rosin flux.  

 

Here's picture of the OEM voltage regulator.  Note the amount of "space" under the leads.  These are what you snip.  I have a "rework" station in my garage which includes a hot air gun.  I was able to easily heat up the chip and pop it off.

 

With the OEM regulator out of the way, we can see how much space we have to work with.

 

This isn't a very good pix, but you can see that I used a tiny pair of pliers to bend the two outer leads "backwards" towards the circuit board.  I bent the center lead in the opposite direction. 

 

Not my best soldering work, but this was kinda tricky.

 

...and I didn't brick it!    

 

Special thanks to @Energy, @elan120 and @pkane2001 
Your pix and instructions helped make this mod pretty straight forward!  

YES! My wife thinks I'm nuts that I've been taking all my meetings / conf. calls at my workbench! 

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Short of discrete voltage regulators I'd be hard pressed to think of any more needed changes for good power...

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9 hours ago, Energy said:

I'm glad you liked it. 

 

But why are your capacitors like that? Having long leads is not recommended especially for (and nearing) discrete voltage regulators. My best guess is that you were trying to use "audiophile" capacitors for a DIGITAL circuit and what looks like Nichicon KZ. 

 

Higher material composition capacitors work best in ANALOG circuitry. Digital circuits on the other hand work better with low ESR capacitors (such as solid type polymer) as it provides quicker charge/discharge, lower output ripple, stability for power control loops, etc. The circuit only calls for higher ESR in various concerns such as regulator stability but other than that, you're more likely degrading more than upgrading your unit. From a technical standpoint I reckon the stock Panasonic FC would perform better in this circuit than the current KZ for two reasons.

 

1. The Panasonic FC should already have lower ESR than the KZ

2. Adding additional length to leads increases resistance (ESR) 

 

Σ₪ergψ 

 

Σ₪ergψ

This is truth... Digital circuitry is super sensitive to parasitic capacitance, lead inductance and voltage losses (of course rfi/emi as well). I'd say in place of electrolytics for bypass/decoupling in digital use, try SMD caps if you can. ESR is almost a non-issue at this point. However, to be more practical in tweaking- in place of KZ, FC etc I would recommend TDK MLCC - C0G (NP0) dielectric (http://www.mouser.com/Search/ProductDetail.aspx?R=FK20C0G1H104Jvirtualkey52130000virtualkey810-FK20C0G1H104J) . These are quite stable across temps and great for this scale of circuit.

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34 minutes ago, T-Bone said:

I just got done replacing mine; and you are right.  It's a pain in the *ss.    ....at least it was for someone with my "neophyte" soldering skills.  I'm sure a more skilled tech would have blazed through the job.

 

...but at least I didn't "brick" my SU-1.  It's back in my system now and I'm giving it a listen.  

Since there's no way to listen to the changes back-to-back any listening impression would be based purely on memory.  So I can't say whether new caps make an audible difference or not.  

(unlike the regulator swap whose improvements were very apparent)  

It certainly doesn't sound any worse and I enjoyed the challenge.    

 

This is a good point. I've had similar experiences replacing things like voltage regulators with massive improvement. Think of how much even the top of the line regs cost versus some top of the line caps or even worse, cables.

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Agreed- I went through the same decision making process and realized that putting my $ into a nice IIS bridge (SU-1) is the next best move after getting a mrendu.