AudioSector-chip amp kits, dacs, chassis

[Peter Daniel]

8414 vs. 8412

I listened some more and CS8414 indeed seem to have more powerfull bass. The chip is not that bad actually, but it has some edginess that is a bit bothering.

 

[Destroyer OS]

On the panasonic FC capacitors the unmarked side is positive, the long lead side correct, for both big and small ones in the 3875 kit?

Any one? I just want to make sure....

 

[Peter Daniel]

For all electrolytics, the long lead is always "+" ( as the unmarked side).

 

[Destroyer OS]

I just wanted to double check. It has been some time since I worked on electronic stuff.

Thanks Peter.

 

[taj]

PCB renovations

Hi Peter,

Do you know of an easy way to cleanly cut apart the 4780 PCBs at the score lines -- after it has been assembled? I've decided to rethink my assembly plans and mount the boards separately, rather than all in-one as I originally planned. Except now it's populated and a little more fragile to muck with.

Any advice?

Thanks,
Todd J.

 

[Peter Daniel]

Just break it off, the score line is pretty deep and it shouldn't be a problem.

Peter

 

[jleaman]

I use a exacto Knife along the lines that you will be breaking it helps a little and keeps them a little cleaner. And help's when snapping them.

j'

 

[Peter Daniel]

You don't need to use knife on GC boards, they break off perfectly.

 

[hayena]

DAC maximum sample rate

Hi Peter,
you already mentioned the DAC works only for red book CD standard. Would it be posible to mod to allow other sampling rate like 48kHz, or 96kHz? Or is it totally different device? Sorry, just not experienced at digital audio at all...

 

[karma]

peter if you get the chance can you post a pic of your dac with the
wood and plexyglass. your right it sounds better without the case. i wana try your idea.


thanks.

 

[wdavis009]

Peter,

I just noticed Digikey is no longer stocking the MUR860's. What do you suggest as a replacement? For some reason I keep killing diodes every time I modify the power supply.

 

[Peter Daniel]

Maybe MUR820, but I can't think of any replacement yet, as long as they are available. There are places where you can still get them and presently I have 3K in stock. Digi key will carry lead free version in April.

You can get MUR860 directly from me as well.

 

[Peter Daniel]

peter if you get the chance can you post a pic of your dac with the
wood and plexyglass. your right it sounds better without the case. i wana try your idea.

That enclosure was posted here: http://www.diyaudio.com/forums/showthread.php?postid=736473#post736473 The acrylic top is mostly decorative and you don't really need it. Don't tighten the screws either.

 

[Peter Daniel]

Re: DAC maximum sample rate

Hi Peter,
you already mentioned the DAC works only for red book CD standard. Would it be posible to mod to allow other sampling rate like 48kHz, or 96kHz? Or is it totally different device? Sorry, just not experienced at digital audio at all...

The DAC uses old technology and it will not work with 96kHz.

 

[patriz]

Why do you need the 4,7mf on the dac output? Maybe to prevent to much offset?

 

[Peter Daniel]

The offset from the DAC chip is approx. 3.5V, you need that cap.

 

[karma]

thanks for the pic. this should work not sure how the tube buffer
got in there but i tryed it sounds good. doh

now to finish the base and wire it up nice

 

[sdedalus]

Peter, Thanks for the quick delivery on the dac kit. Got it today, tossed it together this evening, and plugged it in about an hour ago. Sounds great. Now I just have to wait for the buffer kits.

 

[markgall]

Hey Karma,

What circuit are you using for the tube buffer? Which tube? Do you have a schematic? Are you using another transformer for the tube buffer or powering it from the dac transformer? I've decided I'm going to get one of Peter's DAC's and was thinking I may like to add a tube buffer also.

Thanks,
Mark

 

[Peter Daniel]

Peter, Thanks for the quick delivery on the dac kit. Got it today, tossed it together this evening, and plugged it in about an hour ago. Sounds great. Now I just have to wait for the buffer kits.

The buffer kits are almost ready. I got the boards already, all semis, and I'm only waiting for Dale resistors now.

Also, the Integrated Amp chassis should be available in two weeks or so.

Yesterday, I implemented the Patek circuit in that chassis and it came out really nice. Also, it will be possible to use that chassis for a preamp, using either AD815 (it mounts exactly same way as LM3875) or the buffer boards.

The toggle switch on the bottom disconects potentiometer from a signal ground allowing to use one set of RCAs as direct amp input (Integrated becomes power amp then)