F6 Illustrated Build Guide

[zman01]

lhquam,

Does the Wayne BA 2018 Linestage fit the bill?

The Salas DCG-3 and the AKSA-Lender Preamp are two other projects that come to mind.

 

[lhquam]

lhquam,

Does the Wayne BA 2018 Linestage fit the bill?

The Salas DCG-3 and the AKSA-Lender Preamp are two other projects that come to mind.

I considered Wayne BA 2018 Linestage, but it seems like overkill. I haven't recently looked at the others.

I might consider a 1:2 step-up transformer if the F6 wasn't already using transformers which limit then bandwidth and introduce their distortions.

 

[angrypat]

BA3 pre has more gain than Wayne's I believe.

 

[ColinA123]

I use a BA3-pre with my F6 and am very pleased.
I suppose the "ultimate" if you want a step up system would be Zenmod's Iron pumpkin / turtle.
There are some nice looking step up transformers on E-bay, but no idea of real world performance.

 

[Monk55]

Been running F6 with various pre’s for I’d say 20 cycles @ 4 hours a cycle. I checked bias it was .330 both sides & offset was under .005. Why does the bias drop?? I warmed it up considerably when first built with all sheet metal/case enclosed. I set bias @ .6. Ive reset and staying hooked up to see what transpires. Any thoughts are welcome.

 

[Cooler King]

I asked earlier about some parts and values that I've ordered. I didn't ask about this one, the safety capacitor - https://www.mouser.co.uk/ProductDetail/81-DE2E3SA332MA3BY2F/
It's already on it's way, is it ok for 230v? If not I'll have to find another from somewhere.. If so, which one would you recommend please?

Thanks in advance for you help!

 

[Dennis Hui]

Looks fine.

 

[Cooler King]

Looks fine.

Thanks Dennis

 

[hayenc]

Completed my F6 build today. Got caught on the LED polarity being different on the two boards and also had to follow the change of R7 & R8 to 3.3K and use 6.8 volt zeners. One channel seems more stable on bias than the other, even after an hour so will monitor it. Chassis is one I bought over 10 years ago, EBay I think.

 

[angrypat]

Looks great, put some music through it, it'll make you smile!

 

[hayenc]

Music is flowing. Using B1 Korg NuTube preamp which does mate very well with it. Such detail. I had forgotten how good Class A sounds after having to stop using my Aleph 2's in the Phoenix summer.

 

[jameshillj]

You might like to add some holes in the bottom plate (and maybe top plate, too) to get some internal air circulation going to keep temperature down.

 

[Zen Mod]

some spacers, at least 5mm long, between bottom plate and mounting circumference of box, could help

same applies to top

longer screws and 5mm long sleeves, all solved, without need to dismantle everything for making holes

 

[hayenc]

Thanks. Put in the spacers top and bottom for now. Will look at longer term solutions.

 

[Yaho]

Using B1 Korg NuTube preamp which does mate very well with it.

I have the same match up. They do sound good together. I just finished building the Pearl 2. And she sings beautifully with B1 and F6.

Congratulations!

 

[ChrisM91]

What's the current consensus on the best resistor (R7/R8) and Zener combo for biasing the IRFP240s?

Does the Zener rating matter? I thought I was reading earlier in the thread that lower power rating offer better noise performance.

 

[Bare]

I thought the F6 transformers serve as Buffers ??
If so? is there any purpose in using a B1 ?

 

[Zen Mod]

input JFet pair is serving Buffer role, while xformer is serving as phase spliter** thingy

good one and funny one

** stage which is transforming one SE signal in two opposite ones

 

[angrypat]

Stupid question here, is that what makes this amp a push pull, or am I being stupid.

 

[angrypat]

Would love to build another, Pico style, to compare!