My ACF pre.

pre65 · Post by **pre65** » Mon Sep 02, 2013 10:06 am

David wrote:
I look forward to your impressions!
David

So do I.

Good thing is that, apart from the resistors I've ordered, this has cost me bugger all.

Ali Tait · Post by **Ali Tait** » Mon Sep 02, 2013 12:05 pm

David wrote:IMHO, Kiwame's are very good, with no real vices. The Vishays/Charcrofts are better still but at silly prices from HFC at least. I don't know Takmans. But I'm just using the stock resistors-carbon film-and my only upgrade so far is a Mundorf input cap, I moved from my Pre3, and it sounds darn, darn good!

I look forward to your impressions!
David

Takman well worth a go IMHO, cheap too!

IslandPink · Post by **IslandPink** » Mon Sep 02, 2013 6:40 pm

Other good resistors :
Dale non-inductive wirewound 2w and 5W
Mills non-inductive wirewound 5W and 12W
Russian non-inductive wirewound from EBay.
BI Industries Planar film resistors ( 5W and 10W ) from RS .

The latter are the best performance/price power resistors I've found so far, just a bit fiddly to use as the leads are short and intended for through-hole PCB mounting .

I wonder if we could club together somehow before next Owston & buy some of these Russian ones, which tend to come in 10's or more, eg. boxes of 50 or 100 . Then we could divide out say 10 each for our 'stores' . The different values come in dribs and drabs, though .

pre65 · Post by **pre65** » Mon Sep 02, 2013 10:59 pm

Are x caps classified as film caps ?

pre65 · Post by **pre65** » Tue Sep 03, 2013 2:49 pm

My resistors came about 13:30, and I've just finished populating the tagboard for one channel.

I used x caps for decoupling and Clarity caps for in/out.

Having a cup of tea and a rest now.

Toppsy · Post by **Toppsy** » Tue Sep 03, 2013 4:59 pm

David says of his ACF pre -- "vocal articulation to die for "

What you mean the gurgling strained sound when someone is being strangled. Hee Hee

You'll soon have to move house Phil or find more floor space. When ya gonna start to put all your breadboards in nice neat boxes? Or does that sorta defeat the object?

Fast work there our Phil and ignore the snide remarks about the size of your PS.

pre65 · Post by **pre65** » Tue Sep 03, 2013 5:02 pm

Toppsy wrote: Fast work there our Phil and ignore the snide remarks about the size of your PS.

I'm sure you meant to use another word rather than "snide" Colin ?

I think of it as good humoured banter.

pre65 · Post by **pre65** » Tue Sep 03, 2013 11:03 pm

I'm still sat here soldering !

I'm on the last job now, wiring up the Tocos volume pot.

It will have to wait till tomorrow for the final inspection and initial test. Looking forward to that.

pre65 · Post by **pre65** » Tue Sep 03, 2013 11:33 pm

The days work has finished.

Here is the (I hope) fully wired up ACF pre.

Cressy Snr · Post by **Cressy Snr** » Wed Sep 04, 2013 7:57 am

Does it go?

pre65 · Post by **pre65** » Wed Sep 04, 2013 8:14 am

SteveTheShadow wrote:Does it go?

After the photo was posted I went to bed.

It's a new day now (rather autumnal

) so when I've gone through my morning routine I'll be back on the case.

I hope to have more news before lunch.

pre65 · Post by **pre65** » Wed Sep 04, 2013 9:47 am

OK, testing time.

It seems the circuit is not drawing any current.

So now I'm going through all my wiring up to find out why. Initial inspections can't find any problems.

Ho hum.

pre65 · Post by **pre65** » Wed Sep 04, 2013 11:26 am

I found a ground wire on the wrong tag.

So I've sorted that out, added a bleed resistor onto the last PSU cap and re-sized the HT drop resistor. Should that drop resister be decoupled with a cap ? If so what size ?

So now it looks good for a sound test.

I'm off out shortly for a lunchtime concert (choral today

) so no more till I get back.

Mike H · Post by **Mike H** » Wed Sep 04, 2013 11:40 am

Still don't know what an "ACF pre" is or what's special about it, any chance of a schematic?

Dave the bass · Post by **Dave the bass** » Wed Sep 04, 2013 11:42 am

Akido Cathode Follower I think Mike.

DTB

audio-talk

My ACF pre.

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