F5Turbo Illustrated Build Guide

Question for 6L6

6L6
I have most of my parts assembled but I need to know if I should run two speakers protection boards, to stay true dual mono. I am running dual inrush boards, one per channel. The build is a dual mono F5T with twin 1000VA trannies and 264,000uf per channel. Is it necessary for two speaker protect boards or will one do the trick? I will be putting these on riser panels attached to the front panel as I am running out of room on the chassis floor. I also need to fit in two more 80VA transformers to run the auxiliary boards.

Thanks
 

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Thank you Zen Mod

I will order the parts. I already have the boards.

I also may have to beef up the bottom panel as the weight of the 4 transformers alone is 40 lbs. Anyone have ideas on how to do this? I was thinking of running two pcs of 1/2 angled aluminum across the bottom, one under the trannies and one under the power supply boards to stiffen things up a bit. There are extra holes on the bottom panel to bolt into the stringer.
 

6L6

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Alex, sorry, I just now saw these questions...

Not yet...:). It is behaving very nice, so far.
No oscillations observed, but I use Toshiba MOSFETs.

If it oscillates you'd know as it burns up the output devices instantly. :hot:

Can you please describe again (or direct me to the relevant thread) all confederations behind usage of cascoded JFETs?

Advantages are that you can run higher voltage rails, and get more power, without harming the Jfets. The Cascode keeps the total Jfet voltage within their safe range.
 
Alex, sorry, I just now saw these questions...


If it oscillates you'd know as it burns up the output devices instantly. :hot:


Advantages are that you can run higher voltage rails, and get more power, without harming the Jfets. The Cascode keeps the total Jfet voltage within their safe range.



Hi Jim,
Thank you a lot.
Yep, no oscillations and all is great.
I targeted for 32VDC for PSU and replaced transformer for 25V instead of previously used 24V. Same Antek, but 25VDC out. Unfortunately, I did not get targeted 32VDC. Have about 28-29VDC depend to main fluctuations during day time. My line also a bit sagging when both mono locks and the rest of gear are on. Main is drops to 116-117VAC from 119-120.
Have question about speaker protection devices that guys were talking here. I have stereotype (I thing as read some articles in the past about this subject) that all types of active speaker protection staff is degrading SQ. So, use CL-60 only for inrush and nothing else. Does it make sense to try some more protection for speakers against short? Any advice for specific one? Or not to wary about that at all? Thank you again.
 
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