I got mine from Hotrox and I asked them for a well balanced one. Not fitted it yet so we'll see whether it is or not. I do hope to generate some of that 'bloom' that I hear in other OTS's

I have long thought my OTS doesn't exhibit that 'bloom' you hear on good ones and I do know my PI is not very well balanced, when I set the trimmer I couldn't get it to closer than 12volts. I now have a Sovtek 12ax7LPS, sold as balanced so I need to do this again.

It seems setting it by DC voltage is not the right way to do it. AC voltage on the PI plates is what Andy Fuchs was suggesting. Others suggest that is the right way to get it in the ballpark then do it by ear. The information about maximising the second harmonic was very useful and it should be easy to set by feeding a signal tone into the PI and checking the output using a spectrum analyser (my hotplate will suffice for this, a dummy load and a line out).

I've just  found this one

http://www.sillanumsoft.org/prod01.htm

and run it on my laptop and it works fine. I already had a 440Hz sample file on my laptop (for fooling my Canon 7D into not using the AGC  whilst videoing) and I got a nice clean spike at 440 a smaller one at 880 and a similar one at 1320. I'm not sure whether thats the right frequency to use but I might also try 1000Hz.

a coupling cap between treble cap and slope R?

I have used cooking foil (weak and will need replacing regularly if you take the chassis out regularly) , adhesive copper foil (better, and the adhesive reacts to heat so place it and warm it with a hot air gun) and nothing. Nothing works great!

You'll have DC on that pot.

Very nice indeed. Who made the cab?

Would you do me a favour? Have a look inside to see how the front baffle is constructed. Is it two pieces with tolex applied to the top piece and grille cloth/white piping to the bottom piece and then held together with brackets? or is it one piece with the the materials meeting at a slot?

Many thanks

Hywel Harris

Yes, expose about 20mm of the braid, unwind it, twist it together and solder a piece of wire to it. Cover the  solder joint  and the exposed braid with heatshrink. If you have two adjacent shields to do twist them both together and use heatshrink to hold both wires together.

At the other end cut the shield off flush with the insulator and cover with heatshrink. (it isn't connected)

Tip: when twisting the heater wires in a drill chuck before you release run a hot air gun over the wire to warm up the insulation. When it cools it won't unwind.

This company

http://mec-pickups.de/modules/products/product.php?katID=15049&cl=EN

makes dual/triple/switch combination pots so theoretically you could moun the HRM on the fron fascia using the existing holes. Two downsides as I see it, they are expensive and you wouldn't be able to use chicken head knobs. I am undecided whether to do this for my next build or not. First off I need an excuse to get another amp!!

Glad you enjoyed it chaps. I've never seen him play a bad gig yet.

And don't forget the delay is a big part of his sound.

He's not been using the TR CRS for quite a while. He's got a custom single channel, dual valve rectifier 50 watter now. Coming out as a signature model possibly. Talk to him at the show and he'll give you the latest details.

Tell him Hywel (pronounced 'howell' ) sent you !!

He's in your vicinity this week

http://www.mattschofield.net/shows.html

+- the signal amplitude.

How is that being done? Putting a big coupling cap before it? or using a switch capable of 500v DC? I've though about it, but would like to do it with a mini toggle and I don't believe they are rated high enough unles I am mistaken.