Brown Note D'Lite 44 Schematic ??

[M Fowler]

Here is the info for the Brown Note transformers.

BrownNoteHTS-8816EX.jpg

650EX_15WIRE_PT.jpg

BN_OT_01 (2).jpg

[samrock55]

The very last layout I'm try to 100% verify this is the 44 watt job and not the 22 watt model?? Does anyone know for certain? Thanks for anyone's input to this question

[samrock55]

Thanks for demystify the transformer question

[samrock55]

I have feeling the multi impedance output transformer was for the 22/33 and the 44 was the 6L6 / El34 conversion?? Because that would make the B+ voltages a little more manageable IMHO?

[pompeiisneaks]

Just quickly looking at datasheets, the 6V6 want's 8500 ohms load resistance at 315 VDC, and the 6L6 wants about 4500 ohms at 300 VDC, so basically yes that's an impedance mismatch. EL34's want about 3800 ohms at 350 VDC. the 6L6 and EL34 are much closer and thus why they work fine for a swap out, but they do need different negative bias, so you'd have to make sure that any amp designed to support both has enough negative bias range via either a pot or some kind of switch to add/remove extra resistance in the bias circuit to swap between the two...

~Phil

[samrock55]

Thanks Phil!

[samrock55]

Would anyone know a simple switch Bias circuit to switch between the 6l6 and El34 did anyone lift anything from another design maybe? Thanks

[samrock55]

I know Boogie has something and the old Crate turbo valve 50 was fully automatic with no switch!

[S a m]

Would anyone know a simple switch Bias circuit to switch between the 6l6 and El34 did anyone lift anything from another design maybe? Thanks

a> Build it with the switch physically in place but out of the circuit
b> Bias for 6L6, measure the bias pot
c> Swap in EL34, measure the bias pot
d> Install the switch using resistors to insert the difference

[pompeiisneaks]

Would anyone know a simple switch Bias circuit to switch between the 6l6 and El34 did anyone lift anything from another design maybe? Thanks

a> Build it with the switch physically in place but out of the circuit
b> Bias for 6L6, measure the bias pot
c> Swap in EL34, measure the bias pot
d> Install the switch using resistors to insert the difference

yeah this is a great way. Basically record what bias resistor you need 'with' the bias pot, to get it in range in either case, and then have the switch switch between resistor a and b. (or just add the difference between a and b with a switch).

~Phil

[samrock55]

Thank you Phil it's a differential bias switch then cool!

[samrock55]

I'm using an old Crate 60 watt iron from an old turbo valve from 1997 here is a autobias circuit that looks pretty promising I think I will try this auto bias circuit it was designed to power either set of power tubes 6l6 or EL34s

[samrock55]

-62 negative bias should get it done

[samrock55]

This circuit I am leaning towards though more precision and you can use unbalanced sets of tubes and have optimal biasing thanks Rob Robinette for this one wherever you are

[samrock55]

I wonder if anyone can tell me the difference in to between the skyline D'lite and non with just pab and bright switches?? I'm trying to decide which ONE to build for tonality?? I like a big punchy amp.... If anyone has input I'm willing to try and build a few