[wushuliu]

Quote:

Never listened to acetate cap. 
Would be nice to compare it with Russio PIO caps. Gonna order a pair =D


 

Let us know what you think. Never heard of them myself. I am a fan of the russian PETP (polyester) caps. May give those a try next w/ the Muse...
 

 

[eclein]

I'm getting one in the beginning of next month and I have the Parts Express Power Supply I'm using with my SB that will work with this Muse right??
Is there a visual diagram of some sort for us new, new guys so we can see what is what and be on the same page when we talk about "Output caps" etc.. I haven't soldered in awhile but I'm sure if I use linear PS that will help and any kind of mod I could do to easily make it better I'll gladly figure out and do I'm just not sure what can stay and what should go. We all had to start somewhere.....
 Ed

 

[wushuliu]

Quote:

I'm getting one in the beginning of next month and I have the Parts Express Power Supply I'm using with my SB that will work with this Muse right??
Is there a visual diagram of some sort for us new, new guys so we can see what is what and be on the same page when we talk about "Output caps" etc.. I haven't soldered in awhile but I'm sure if I use linear PS that will help and any kind of mod I could do to easily make it better I'll gladly figure out and do I'm just not sure what can stay and what should go. We all had to start somewhere.....
 Ed

Hi Ed, here is an earlier post with good photos and labels. 

 

[viatraco]

Which will be best choice for our Muse for output capacitors instead of Elna RBP2 10uF/50V ?
 
http://allegro.pl/mkp10-wima-10uf-250vdc-do-audio-super-cena-i1642154829.html
http://allegro.pl/mkp1839-10uf-160v-roe-vishay-osiowy-2-sztuki-i1615074962.html
http://cgi.ebay.pl/Black-Gate-STD-10uF-50V-capacitor-for-audio-/150607585085?pt=LH_DefaultDomain_212&hash=item2310e95f3d
 
Price is similar circa 5$ / pair
Sonic target : more highs smoothness and better bass control

 

[ETAHL]

 
Quote:

Which will be best choice for our Muse for output capacitors instead of Elna RBP2 10uF/50V ?
 
http://allegro.pl/mkp10-wima-10uf-250vdc-do-audio-super-cena-i1642154829.html
http://allegro.pl/mkp1839-10uf-160v-roe-vishay-osiowy-2-sztuki-i1615074962.html
http://cgi.ebay.pl/Black-Gate-STD-10uF-50V-capacitor-for-audio-/150607585085?pt=LH_DefaultDomain_212&hash=item2310e95f3d
 
Price is similar circa 5$ / pair
Sonic target : more highs smoothness and better bass control

 
Skip the output capacitors. Just use jumpers. They are free.

Most, if not all, amps have input coupling capacitors. You would just be removing an extra set of capacitors in the chain.

 
 

 

[ETAHL]

Just got my Muse DAC and burning it in after a few mods.

 
Most of the heat from the DAC is generated by the LM317T voltage regulator. It is cooking using a 12VDC power supply. I think that is the source of the overheat problem, especially in a small enclosure. Using a lower voltage power supply will definitely help significantly in reducing the heat given off by the LM317T. Also the tab of the LM317T is not solder to the PCB plate underneath. I applied some solder and it helps to distribute the heat to the other side of the PCB, away from the components.
The heat from the TDA1543s are minor in comparison. The stock heat sink and compound are not very effective. I mover the four 100nf capacitors to the other side of the PCB and replace the stock heat sink with a spare set of video RAM heat sinks, which work much better.
Added a couple of jumpers, shorting out the stock Silmic 10uf output capacitors.
The red power LED is replaced with a green one.
 

 

[mgburch]

 
Quote:

 
 
Skip the output capacitors. Just use jumpers. They are free.

Most, if not all, amps have input coupling capacitors. You would just be removing an extra set of capacitors in the chain.

 
 

Whoa! Not all preamps, amps, integrateds and receivers have coupling caps. Nelson Pass, for example, is fond of DC coupled amps and has designed quite a few. Some of his designs were used by Nakamichi and others. Don't blow up your headphones/speakers! Google "fully DC coupled amplifier" for more info.
 
While I do agree no cap is best, this isn't going to work for everybody, OK?
 

 

[wushuliu]

Quote:

 

Whoa! Not all preamps, amps, integrateds and receivers have coupling caps. Nelson Pass, for example, is fond of DC coupled amps and has designed quite a few. Some of his designs were used by Nakamichi and others. Don't blow up your headphones/speakers! Google "fully DC coupled amplifier" for more info.
 
While I do agree no cap is best, this isn't going to work for everybody, OK?
 

+1
 
I can't do it with my tube amp for instance. Some people might experience a nice big turn on thump(!) as well. Gotta be careful with blanket statements.
 

 

[mgburch]

 
Quote:

Just got my Muse DAC and burning it in after a few mods.

 
Most of the heat from the DAC is generated by the LM317T voltage regulator. It is cooking using a 12VDC power supply. I think that is the source of the overheat problem, especially in a small enclosure. Using a lower voltage power supply will definitely help significantly in reducing the heat given off by the LM317T. Also the tab of the LM317T is not solder to the PCB plate underneath. I applied some solder and it helps to distribute the heat to the other side of the PCB, away from the components.
The heat from the TDA1543s are minor in comparison. The stock heat sink and compound are not very effective. I mover the four 100nf capacitors to the other side of the PCB and replace the stock heat sink with a spare set of video RAM heat sinks, which work much better.
Added a couple of jumpers, shorting out the stock Silmic 10uf output capacitors.
The red power LED is replaced with a green one.
 

Good tip on the reg. Isn't it wired to output 8V? So how low can the power supply be? I think the LM317T needs to drop a couple of volts, right? I wonder if its possible to fit a heatsink on the 317?
 

 

[ETAHL]

 
Quote:

 

Good tip on the reg. Isn't it wired to output 8V? So how low can the power supply be? I think the LM317T needs to drop a couple of volts, right? I wonder if its possible to fit a heatsink on the 317?
 

That is correct, you need some voltage drop for the regulator to work. You need a minimum of 1.3 volt drop. If you can supply it with 10VDC instead of 12VDC, the heat output from the LM317 is cut in half.
 
Instead of a heatsink on the LM317, which will still dump heat inside the enclosure, I made a thermal bridge connecting it to the aluminum cover. I made an aluminum bar and sandwich it between the thermal pads that I recycled from under the stock TDA1543 heatsink. 
 

 
 
I also found a problem with the MUSE DAC. The DAC will clip and distort if you input line level optical and coax signal. The only way to have a clean output, I had to reduce the volume in software from a PC. You are SOL if you are using any hardware digital source such as CD, DVD, digital media player.

  Does any one also have the same problem?

 

[scottiebabie]

Quote:

Whoa! Not all preamps, amps, integrateds and receivers have coupling caps. Nelson Pass, for example, is fond of DC coupled amps and has designed quite a few. Some of his designs were used by Nakamichi and others. Don't blow up your headphones/speakers! Google "fully DC coupled amplifier" for more info.
 
While I do agree no cap is best, this isn't going to work for everybody, OK?
 

LOL i think posted way back when that this lil Muse Mini sucka pumps out somtin' like 3.7v DC sans coupling caps. so if one coupled this Muse to a DC coupled amp with a gain of...ooo say 16 (which is real low btw) the output at speakers could be as high as 59v DC.
 
sooo yaaaah i'd have to say 59v DC miiiite just be 'nuff to melt voice coils to say the least. beside checking the service manuals, DMM at speaker taps the best way to check if one has a true DC coupled amp. either feel the amp some DC mv or feed a short'd Muse (or whateva) & measure at amps output which happens to be the speaker outs/taps. 
 
btw @ETAHL nice heatsinks on em TDAs.
 

 

[wushuliu]

Why not just get rid of the 317 and use a  Teradak PS calibrated for 8v straight to the PCB? This is what I will do with the Salas PCB...

 

[ETAHL]

Quote:

Why not just get rid of the 317 and use a  Teradak PS calibrated for 8v straight to the PCB? This is what I will do with the Salas PCB...

Sure you can do that, just that it adds cost and bulk. I would leave the LM317 in and adjust the Teradak PS to 9.5VDC, this way you have two regulating stages.
Leaving the cover off lets a lot of heat out too.

 

[ETAHL]

Sure. Better to be safe than sorry. However, if you know the amp you are using has coupling capacitors, there should be no problems. All my headphone amps have them.
 
DC coupled power amps sounds scary. A big gamble that any upstream components are not faulty.

 
Quote:

 

Whoa! Not all preamps, amps, integrateds and receivers have coupling caps. Nelson Pass, for example, is fond of DC coupled amps and has designed quite a few. Some of his designs were used by Nakamichi and others. Don't blow up your headphones/speakers! Google "fully DC coupled amplifier" for more info.
 
While I do agree no cap is best, this isn't going to work for everybody, OK?
 

 

 

[wushuliu]

Quote:

Sure you can do that, just that it adds cost and bulk. I would leave the LM317 in and adjust the Teradak PS to 9.5VDC, this way you have two regulating stages.
Leaving the cover off lets a lot of heat out too.

 
I guess I'm thinking more of those who've gotten farther with modding, coupling caps and all - then the enclosure should just be tossed...
 
Ha! if you're DIY addict, then DC coupled everything is just a matter of time