audio-talk

Ah right, thanks Mike. So no grid leak but any of previous stage output resistance, any of the vol pot in series and any gridstopper and in series so accumulative. Right? Well, no, the grid leak is in parallel with the lower half of the volume pot, the top half is also in parallel via the source, S...

Ah right, thanks Mike. So no grid leak but any of previous stage output resistance, any of the vol pot in series and any gridstopper and in series so accumulative. Right?

Hmmm, right. Presumably then grid leak resistor, volume pot and previous stage ouput resistance should all be in parallel to give R?

I've been thinking about the affect of Miller Cap on high frequency cut off. Miller cap = (gain+1) x Cag plus a few strays and f-3 = 1 / (2 x pi x C x R) C is Miller cap, but what is the appropriate value to use for R? Morgan Jones talks about the output resistance of the previous stage, but what if...

Good as they are, the maximum current rating the seller gives is woefully over optimistic. When I tried them on GM-70 filament supply at 3.5A they got "Bloody Hot" :shock: I still use them on other projects but would suggest 2A was a realistic maximum. Would agree with that Phil. They run...

How much current does the Pre 3 draw? Perhaps drop the voltage with a couple of VR tubes and has the added benefit of shunt regulation?

Yes, very impressive indeed.

12GN7 would be great

It would look rather odd if I now deleted my post...

I wasn't sure what an SSR was (solid state relay!) is so I looked it up on Wikipedia and got a list of possibles, including scrotum self-repair. WTF I thought, I clicked on it and it doesn't get any better... http://en.wikipedia.org/wiki/Self-surgery

That's interesting Ray, I hadn't thought about the filter module being a problem in OBs. Steve uses his in his baffles but currently only over a relatively narrow band. His previous OBs were pretty much full range though and sounded pretty good to me. I wonder what Lowther might charge for exchangin...

Steve,

How far down do you reckon your EX4s reach? Or to put it another way if I wanted to cross them over with a bass helper in OB where would be a good place to do it?

Simon.

So you're a princess our Andrew?

thomas wrote:Is it this critical, anyway?!

Dunno, I haven't tried ultrapath yet. IIRC Broskie talks about parallelling caps to fine tune capacitance and null the noise. But whether you can hear it I don't know.

Ultrapath cap Thomas? If so it's based the valve's mu. http://www.tubecad.com/2008/08/blog0147.htm

Monster. Come on Mark, spill the beans .