Thanks Ian,
Am ready to go on your version of the ecl86 huey!
Think I will just breadboard one channel and try to get an understanding of the cicuit, I will be aiming for a B+ of approx 300V so I assume I don't need to 60uf 900V cap?
And I am using 0 - 3ohm - 15ohm output trannies so I am going to try and forego the gnfb as I do not know how to use it, I will be driving tannoy monitor golds so I may just connect onto the 3ohm tap, do you have suggestions on this?
cheers stuart
Am ready to go on your version of the ecl86 huey!
Think I will just breadboard one channel and try to get an understanding of the cicuit, I will be aiming for a B+ of approx 300V so I assume I don't need to 60uf 900V cap?
And I am using 0 - 3ohm - 15ohm output trannies so I am going to try and forego the gnfb as I do not know how to use it, I will be driving tannoy monitor golds so I may just connect onto the 3ohm tap, do you have suggestions on this?
cheers stuart
No you don't need the 60uF/900V capacitors. I was experimenting with an all polypropylene capacitor power supply (no electrolytics) to see if it gave noticeable benefits and they were the only larg'ish polyproplylene capacitors In had in my parts bin.
In recent years, electrolytic capacitors have improved dramatically, due mostly to the demands imposed on them when used in switchmode power supplies. I would just use electrolytic capacitors.
What is the nominal impedance of the Tannoys, If 16 Ohms use the 15 Ohm tap, if 4 or 8 Ohms use the 3 Ohm tap.
Cheers,
Ian
In recent years, electrolytic capacitors have improved dramatically, due mostly to the demands imposed on them when used in switchmode power supplies. I would just use electrolytic capacitors.
What is the nominal impedance of the Tannoys, If 16 Ohms use the 15 Ohm tap, if 4 or 8 Ohms use the 3 Ohm tap.
Cheers,
Ian
They are 8ohms I believe, should I just try and build the circuit below without the gnfb and using a 60uf 400V cap in place of yours?
I could then maybe try an learn the bennefits of the gnfb afterwards? I don't believe it is necessary to get a good initial sound from this circuit?
I am going to an infamous fair called the audiojumble in kent UK this sunday - I'm sure i can pick up some nice caps for my PSU there... bit far for you to travle though but I'm sure you'd have enjoyed it!
cheers Stuart
I could then maybe try an learn the bennefits of the gnfb afterwards? I don't believe it is necessary to get a good initial sound from this circuit?
I am going to an infamous fair called the audiojumble in kent UK this sunday - I'm sure i can pick up some nice caps for my PSU there... bit far for you to travle though but I'm sure you'd have enjoyed it!
cheers Stuart
Use 100uF in either 400 or 450V rating, what ever you can get.
You can forgo the 1K and 470R balance "network" although it does help get that last 5% of performance if the triode sections of the 6GW8s are not well matched.
One thing - electrolytic caps are the one component where I would NEVER use second hand or previously used items or items which have been on the shelf for 10 or more years, buy new ones.
Cheers,
Ian
You can forgo the 1K and 470R balance "network" although it does help get that last 5% of performance if the triode sections of the 6GW8s are not well matched.
One thing - electrolytic caps are the one component where I would NEVER use second hand or previously used items or items which have been on the shelf for 10 or more years, buy new ones.
Cheers,
Ian
Thanks Ian, yes new is what I will be buying, lots of audiodealers selling old and new, I was planning on new electrolytics,
If you don't mind I may get in touch with you again once the build is up to try and get an idea of how to 'match' up the triode sections with the 100k pot pan
5% sounds like something I'd like to try once its up and running!
STuart
If you don't mind I may get in touch with you again once the build is up to try and get an idea of how to 'match' up the triode sections with the 100k pot pan
5% sounds like something I'd like to try once its up and running!
STuart
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