D'Lite mid control and extra cap

[dogears]

I know that you want the lows. I think you may find the smoothing of the highs by adding NFB has the effect of warmimng those lows and making them more pronounced. Let me know what you think. Also, make sure you have a 25K presence pot.

I am on the 8 Ohm tab(transformer only has an 8 ohm tab)I`ll give that 68K a try first thing tomorrow morning but i`m still confused.
180-380 herz is low?Where does the mids begin then?
Structo;this Dlite has the bluesmaster PI.
Thanks again,Ed

[Ed de Jager]

Well the 6.2k in a standard Dlite PI.

[dogears]

Ed,

What exactly is in your amp? Is it full blown BM? Please post a pic.

Thanks!

[Ed de Jager]

I don`t have a digital camera but will ask around.
I was answering structo`s question btw.

Ed

[Pete]

I think it is:
4k7 -norm/most common (usually recommended on 4 ohm tap w/100w amp)
6K2 -original D'Lite value (IIRC) (other tweaks here have been suggested)
100k -BM
all variations of the same place in a specified circuit, depending on the amp ... hope I'm not adding to any confusion, including mine. (just trying to follow this also)

OK, so which resistor are we talking about?

[Ed de Jager]

The pictures taken with my wife`s digital camera are much too dark.
Will try again in daylight tomorrow.

Ed

[Structo]

I guess I don't understand what makes a particular PI a bluesmaster.
They all seem to use the same long tail pair. 1M/820R/1M
The only significant difference I have noticed is the way the NFB is configured.

[heisthl]

1M/820/1M are not really the components that make up of what designates an inverter as a long tail pair. The 1m are grid resistors. The 820 is the cathode resistor and the 24K is the tail resistor. In the "Blues master" design the 820 becomes 510 and the 24k becomes 9k1. replace the 390 with a 4k7, the 2k pot with 25k, the 1uf to a .1uf cap, the 4k7 feedback with 100k and add a 47pf across the 2 junctions of Plates to coupling caps to convert.

[Structo]

OK, thanks for clearing that up.

[Ed de Jager]

Here are the pictures.A little blurry,sorry for that.
I was playing yesterday and a guy comes up and askes if i like Pete Townsend because i sound just like him.
Watched a video from an eighties Rockpalast show where he was using telecasters from Sheckter and Hiwatt amps and cabs and indeed; the sounds are very much alike.Strange huh?
I really like this sound though.

Ed

[heisthl]

I would definitly get rid of the siver mica between the plates. Whatever cap you use in that position does not really affect tone it just gets rid of "super highs" that could oscillate. The mica caps are notoriously leaky and prone to going towards shorted, put a ceramic disc there instead. NJMHO.

[Ed de Jager]

Whatever cap,do you mean value?Would a 270pF do?That`s the lowest i`ve got ceramic 1000V.
I really thought silvermica was top quality.That was what i was told.
Thanks anyway,Ed

[Structo]

If you are talking about the snubbers on V2, guys are liking 330pf for that to help with the high end sizzle.
I can't look at the pictures because it wants me to download something for a slide show.......

[heisthl]

Whatever cap,do you mean value?Would a 270pF do?That`s the lowest i`ve got ceramic 1000V.
I really thought silvermica was top quality.That was what i was told.
Thanks anyway,Ed

Maybe I'm loohing at the picture wrong - I'm talking about a 47pf between the PI plates.
Silver Micas are "top quality" if you're talking pristine tone. The reason Dumble didn't use them in his builds was to get the "grainyness" character the ceramic discs have. Many builders/modders like the silver mica caps in the preamp (especially in Fender amps). I use them in my Reverb circuits. It's just that the 47pf at the output of the BluesMaster PI is probably the one place where you really don't want one for reliability issues. If it's your personal amp don't worry about it - I just wouldn't do it if you're making the amp for someone else.

[Ed de Jager]

I understand that but i have no 47pF ceramic.The lowest value i have is 270pF.Can i put that in?
To get a 47pF ceramic i would have to order one and as i don`t need anything else at the moment it would become a very expensive one.
I`d rather postpone ordering untill i need a few other items.

Ed