SNAXO2-4 Nirvana...?

[jonnoshore]

As I now have a SNAXO power supply I was considering doing the equivalent as MR. Tibbs has done with his Traco DC-DC things.

Question: Does anyone know what the pin outs are on the SNAXO 2-4 19 pin socket. I have found a picture of the 52 socket which is powered by a Supercap so will have the same. I assume the ch1/ch2/earth will be the same but not all of the 24vs are needed...

What I was thinking of doing was making a small plastic box which has to house the Traco's and the 6(?) regs in that would be external to the main SNAXO2-4 but would literally sit on the back of the Supercap socket.

This little box would need:

a socket for signal in from 102
a socket for +24v dc in from Hicap to Traco (earthing separate from above)
2 Tracos linking to...
regulators linking to the 24v outputs on the
a 19pin plug output for the SNAXO2-4

The wired from the 'box' to the rails would not be too long ~200mm if the box was right on the socket... I was thinking this way I could leave the SNAXO unmodded...

Thoughts...

Mr. Tibbs could this work? Is the cable length critical or would the small length from the back of the box to the circuit be an issue.

 

[Jiiim]

John,

Quickest way to find out would be to take the lid off and trace it out.

Been meaning to ask you over for a bottle of wine or five for a while now,
bring the snaxo with you and I'll help out. (before the wine...)

Jim.

 

[laverda]

Its been some time since I played with the snaxo's but I'll have a look and post if I can find what your asking for. re: pin in/out, for sure the grd and signal pins are as your drg above IIRC for any snaxo.

Graham

 

[Mr Tibbs]

The wired from the 'box' to the rails would not be too long ~200mm if the box was right on the socket... I was thinking this way I could leave the SNAXO unmodded...

Hmm... that might lose you much of the advantage of the DC converters TBH.

The whole idea of using them in this application is to try to create a 'perfect' 0V point in the preamp (or naxo in this case), where there is no current flowing in a common 0V wire (or wires) back to a power supply.

What about your 102? You should Traco it first before touching the snaxo, that way you'll get a feel for the results this can bring before going at the snaxo.

Mr Tibbs

 

[jonnoshore]

Jiiim,
Yes Wine would be good I have been meaning to do the same... We have some catching up to do... I would sooner drink the wine first ;-) that is my problem...

Mr. Tibbs,
Half the reason for doing it to the SNAXO was the untampered effect... if 200mm is going to wreck the effect I can mod my NAXO 2-4 and slot it in when fininshed...

I have 4 super regs... 2 for Pre, 2 for prefix.
Would 3 1086s be better than a star-SR per Traco??

 

[Mr Tibbs]

Half the reason for doing it to the SNAXO was the untampered effect... if 200mm is going to wreck the effect I can mod my NAXO 2-4 and slot it in when fininshed...

Unless you intend to copy what I have done (Traco's with multiple local 1086's) you should put in place whatever local reg's you want to use (SR's, TPR's etc), and make sure everything is working well first. Only then should you introduce the converters, but they must be fitted very near the star 0V point to do their thing.

I have 4 super regs... 2 for Pre, 2 for prefix. Would 3 1086s be better than a star-SR per Traco??

All I can say is that a DC converter per channel, plus as many 1086's as necessary to cover all of the various circuit feeds (TA filter/buffer/gain/phono/etc), works very well indeed. I haven't tried any other arrangement with the Traco's, so cannot say for sure what might be better or worse. Sorry!

Mr Tibbs

 

[jonnoshore]

Just been rummaging in my box of parts and I have found regulation circuits that I bought of Mr. 'Norton' LP12 power supply man when he had a clear out... I have 7 1086's and numerous capacitors 35v Silmic 22uF in this one box... some desoldering should sort this out...

 

[jonnoshore]

Just taken a look at my NAXO 2-4 (not SNAXO2-4) and the earth point is at the rear of the circuit board near the socket... MMmmmm... If the SNAXO is like that then... the box externally idea should be ok I assume with the bonus of having separate power feeds to the inputs.

Mr Tibbs:
Are the 27 ohm resistors at the 24v feedpoints still needed?

 

[Mr Tibbs]

Just taken a look at my NAXO 2-4 (not SNAXO2-4) and the earth point is at the rear of the circuit board near the socket... MMmmmm...

Fair enough, no harm in giving it a try.

Are the 27 ohm resistors at the 24v feedpoints still needed?

Get them out - much of the improvement on the +Ve side is due to the removal of these resistors. I don't use them at all, though a very small amount of R (a couple of ohms) may have some benefit. Since you have to 'go in' to do this, why not bung the Traco's inside at the same time

Mr Tibbs