Building a point to point Phono II

[RobHolt]

Would you believe it - I've just scoured Farnell and filled out the online order form for just about everything except a couple of high grade caps and the damned thing timed out and reset......Argggggggg

[RobHolt]

Right, all parts now ordered.

I heeded the warning that tants can drift so went for Welwyn metal films (1%) for the resistors, silver mica caps for the RIAA stage and Russian teflons for the 2.2 and 0.1uf caps.
Chassis mount B9A bases from JJ.

I'm now waiting eagerly for it all to arrive

Rob.

PS: How critical is the choice 10uf 450v cap to performance. I have a couple of standard cheap electolytics in my spares box but is it worth using something better?

[NickG]

I would not loose sleep over that cap myself.

[RobHolt]

Confession time:
I've shelved the hard wring idea for now, mainly because I think shoehorning it into the case will be difficult without shorting something.

Now the good news:

I've fitted the upgraded parts onto the Phono II pcb and even after one hours use the improvement is startling!
More depth, better clarity, sweeter top and much,much better solidity and body to the music. The results far exceed what I'd expected - so much so that I'd urge WD to supply the upgraded parts as standard and add £30-40 to the price.

The only problem proved to be the fragility of the pcb. Rather than keep heat applied for long periods and clean out the holes I used a fine 1mm drill bit and drilled them clean using a small craft drill. It helps prevent lifting tracks.

Here are before and after pics:




Rob.

[Black Stuart]

Hi Rob,
so you went for the Russian caps - they are good are'nt they AND they don't cost a fortune either AND they are closer toleranced as well.

Have to agree about the PCBs from WAD.

Do have a think about using Pearl Coolers or the 'rubber bands' from M.Percy in the States - they do help enormously to damp out microphonics.

I bought Pearl Coolers to start with but now use the carbon fibre jackets that came with the Pearls in combo with the 'rubber bands'.

Black Stuart

[Black Stuart]

PS. Rob,
think of something better than using the grey Maplin wire.

Black Stuart

Originally Posted by Black Stuart

PS. Rob,
think of something better than using the grey Maplin wire.

ABSOLUTELY!

The floppy, grey, shielded, twin-core stuff that WAD supplied is not fit to be used as gardening twine! It sounds as soggy and lifeless as it looks.

I replaced mine with IPL IC2 (~£5/m) to great effect.

[colin.hepburn]

Hi All
Whats the best chose of caps for C10/11 C12/13 C18/19

Colin,

Choice of any component is always a matter of taste and opinion, 'best' is very subjective and nobody can tell you what is best for you (*).
I've used Polypropylene types for the bigger value capacitors, and my opinion of the wire is clearly given above! But I do know that many will prefer a different presentation to the one I have got.

There are some more opinions in the recent Phono II Tweaks thread.

* But there does seem to be some consensus that at least two pairs of the smaller value capacitors should be 'Silver Mica' types!

Note that it is probably better to refer to the values of the capacitors in Phono II, as the component numbering changed.

[RobHolt]

Thanks guys,

I have some VDH D501 left over from an arm cable I made recently so perhaps I'll try that. I'm not a cable 'believer' as a rule but it costs nothing to try it as I have the cable.

Such was the change in depth and soundstage width that I had to check that I'd not wired a channel out of phase!

Although I'd been advised that C10 isn't critical I changed it for a higher voltage, closer matched part. A film cap would have been nice but I'd never get the lid back on the case

Next step will be to do the shunt mod to the Pre 2 followed by some bypass trick that Thoresten Loech showed me at the weekend. When I fully understand the schematic he drew I'll say some more

PS: Russian caps were from Anthony Welsh and the S mica and electrolytics from RS and Farnell