Finally, an affordable CD Transport: the Shigaclone story

[Dr.H]

Hi guys, thanks for all the great work; my transport sounds fabulous in standard config.
A few questions:
1. What does C916, C906 and C952 decouple?
2. Why is C952 removed and not replaced?
3. Anyone tried Pete Goudreau's triplets in these positions?
4. Anyone tried OSCON's?
5. herewegoagain has posted pics showing that the spdif output is not rellay improved through reclocking, but that the use of a 300/100 ohm output squares it nicely. Is this consistent with listening tests?
6. Any other caps worth replacing?
7. Any thoughts on the best mechanical approach for the transport? I was going to do an over the top heavy base, but is that the best?
8. Any benefit in using ALW or Teddyregs?
9. Any benefit in using an accurate clock like Guido's etc?

Thanks for any pointers.
Ryan

[Peter Daniel]

You can find service manual here: http://www.ferdsaudio.com/RC-EZ31.pdf

The most critical mods have been described here: The CD Transport

I tried Goudreau triplets some 10years ago, but don't do that anymore as my priorities have changed: The mods never end, adding Goudreau's triplets

My CEC TL0 uses mostly Oscons and sounds great, so it might be good idea try them here as well.

I don't use reclocking any longer, critical listening tests indicated that reclocking was actually degrading sound (into more digitized character). I actually converted my TL0 and friend's TL1 from output reclocking into 300/100 output with positive results.

I tried ALW in some other circuit and wasn't impressed much, my preferred regulator for digital is presently this one: Finally, an affordable CD Transport: the Shigaclone story (courtesy of Bobken)

I tried Tent clock in both CEC TL0 and Shigaclone, and never liked it. I got similar results with two other transports whenever Tent clock was used. I still share Romy's opinion on clocks: GoodSoundClub - Romy the Cat's Audio Site - The clock upgrades: my proposals

[Pocoyo]

Hi Dr H

As shiga talk in the first time by okapi or PD
- removed caps cause it was found degrade the sound
- few builders were tried with oscon but the issue was
the brand of the capacitor here
- Okapi tell us to change bgn/x 47uf, 2x33uf, 2x10uf & 0.1uf
- Eric reported change bgnx 0.1uf to mundorf silver in oil 0.01uf
- PD reported just change bgn 47uf 50v has a good sound
- Eric said that ALWSR better than LM7808
- A few people reported that tricord no 4 was the best for shiga

It will be back to your taste and budget, best regards

Btw if you search for BGF 1000uf 35v I will sell it for US$ 20
I got nichicon fx too 1000uf 63v @ us$ 3

[Dr.H]

Excellent Peter, thanks!
Any comments on the best mechanical approach to the transport. I thought a very heavy base/enclosure would work?

[Peter Daniel]

This approach works very well for me:The CD Transport

It is heavy copper base, mechanism mounted on two standoffs only, wood trim and acrylic top for pleasing appearance mostly

[Dr.H]

Thanks Pocoyo, Daniel.

So C906 is the magic cap in the shigaclone. Has anyone tried to replace or remove its bypass, C908?

Also, is there any sound benefit in fitteing a seperate 5V regulator in additiopn to the 8V supply (i.e. seperate the supplies)?

[aparatusonitus]

Originally Posted by Peter Daniel

I tried ALW in some other circuit and wasn't impressed much, my preferred regulator for digital is presently this one: Finally, an affordable CD Transport: the Shigaclone story (courtesy of Bobken)

This is a very good super-shunt regulator, but you can improve it a bit by spliting 15R resistor in two (like 4R7 for the 1st +10R for the 2nd) in order to make it RCRC filter instead CRC. Also, put lower capacity, lower ESR (in case you use different caps for filtering) closer to diode bridge. You could use, lower noise, constant impedance (thru tens of MHz) 2V5 LED diode or better still 2 x IR diode for opamp voltage reference and BF24x or such J-fet wired as CCS.

[Peter Daniel]

Originally Posted by Dr.H

So C906 is the magic cap in the shigaclone. Has anyone tried to replace or remove its bypass, C908?

Also, is there any sound benefit in fitteing a seperate 5V regulator in additiopn to the 8V supply (i.e. seperate the supplies)?

906 is not a bypass for 906; it's a cap connected to a different pin for a different purpose.

There is certainly possibility of a gain with separate 5V regulator, although LM317 I tried wasn't an improvement.

I'm presently working on a different set of mods, including discreet 5V regulator. I should be able to test it soon.

[Dr.H]

oops, you're right on C908. what is the function of the pin that c906 is connected to?

[uncle_leon]

Peter, you never stop, do you?
You already have what is arguably one of the best CD transports in existence, but that doesn't stop you from trying to make an even better one... And best of all, after doing all the hard work, you come here and give the design for free to anyone who has sense enough to listen to your advice. It never ceases to amaze me.