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I have some 7.5k and 8.25k stepup loading resistors - however ideally I would like a pair with values slap bang in the middle (7.9K). High quality is desired.

I also require two pairs of dc blocking caps that are small enough to fit between underside of pcb and the case - likewise of good quality.

Any suggestions?
 
brizonbiovizier said:
I have some 7.5k and 8.25k stepup loading resistors - however ideally I would like a pair with values slap bang in the middle (7.9K). High quality is desired.

I also require two pairs of dc blocking caps that are small enough to fit between underside of pcb and the case - likewise of good quality.

Any suggestions?
Click to expand...

Black gate NX-HiQ for the cap. Measure the voltage and if you only have a couple of volts the tiny 6.3v version might suit.

For the resistors, Id just order some 1% metal films from RS. Personaly I'm not convinced of audible differences between resistors, though there is with caps.

The Wad phono stage you heard has the Black Gates in circuit and throughout the PSU.
 
Its for the 2nd stage and o/p of a phono stage with 2v o/p so will the tiny 6.3v version be ok? If so - where do I get them from?

Will the resistors fit inside the phono plugs I have attached to the stepup?

Thanks!
 
brizonbiovizier said:
Its for the 2nd stage and o/p of a phono stage with 2v o/p so will the tiny 6.3v version be ok? If so - where do I get them from?

Will the resistors fit inside the phono plugs I have attached to the stepup?

Thanks!
Click to expand...

I've used these Nick:

http://www.hificollective.co.uk/components/black_gate_n_type.html

The 6.3v should be fine if you only have 2 volts there. But, do you mean that the stage has a nominal 2v output (like CD) or that there is 2v dc sitting on the output?
The latter figure is the important one and for a 6.3v cap you'd not want dc above 4-5v IMO to give some margin.
If you have dc present, do I take it that you have dissabled the servos in the phono stage?

0.25w metal film resistors will go into a phono plug.

These look just the ticket and are as near to 7.9k as you'll get:

http://rswww.com/cgi-bin/bv/rswww/s...cckaddigjdijjfcefeceefdffhdgmn.0&cacheID=ukie
 
Nominal 2v o/p like cd

I will put caps after the first and second gain stages so there shouldnt be too much dc at the final stage.

Just about to disable the servos and load up the stepups
 
brizonbiovizier said:
Nominal 2v o/p like cd

I will put caps after the first and second gain stages so there shouldnt be too much dc at the final stage.

Just about to disable the servos and load up the stepups
Click to expand...

Measure the dc voltages at the output of the first and second stages. If it's 5v or less the 6.3 caps will work fine.
You could go up to the 10v parts but they are fatter and will be difficult to fit into a cramped space.
 
I only really need small ones for the 1st stage now I think about it - so 6.3v will be fine.
 
I had pretty good results changing the R's in the filter of my phono from RS 1% to the 0.1% they do (welwyn I think). Take that as you will :)
They do bump the price up a fair bit though and I had to do some fiddling to get the exact values I needed, the upside being I didn't need to use any wires inside for point to point.
 
I'll give the part number instead:

RS Stock no. 166-627

+/- 0.1% - nice :)
 
I'd not use blackgate ........but I never feel the break in and if the kit is left powered down, ime, you start all over again. I've had fantastic liquid [fluid] sounds from paper in oils or not as good [but better than blackgates] stacked wima 1uf foils. If you you want a few to try pm me.
 
I'm in agreement with Pete here, having used b/g for many years, I found they simply 'stuff the music', whilst I know they do improve many areas of the presentation, you will NOT FIND ANY in the work the we perform.
 
......any suggestions ? I'm always trying different caps but there are only a few I've found really help the sound in this application.
 
zanash said:
I'd not use blackgate ........but I never feel the break in and if the kit is left powered down, ime, you start all over again. I've had fantastic liquid [fluid] sounds from paper in oils or not as good [but better than blackgates] stacked wima 1uf foils. If you you want a few to try pm me.
Click to expand...

Pete, I agree that PIO can be better, but as I read it Nick needs them so sit under his pcb in his shallow case which is why the BG-n 6.3v are suitable - they are tiny.
 
BBV: Do you have to mount the caps under the PCB? What about running flying leads from the caps to the pcb holes and sticking the caps elsewhere in the case if you have room.
 
What about running flying leads from the caps to the pcb holes and sticking the caps elsewhere in the case if you have room.
Click to expand...
In general this isn't a good idea if the cap preceedes a fairly high-gain stage; the additional loop area can pick- up enough RFI to be a problem.
 
I'd have thought DC blockers would be on the output. Are they even necessary anyway?
 
Hmm thats an option ... I have ordered some smaller resistors and caps from robs suggestion and will see what I can do with the originals - I dont want to get half way through and have to stop to wait for parts!
 

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