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6V6 line preamp

diyAudio Chief Moderator
Joined 2002
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I have used much club stuff on it and it was vigorous, just referred to what I did stick there lately when I was re-testing. Here is the FFT I just took again BTW. Its with a 100K Black beauty pot at half way with 0dBu input. (65536 FFT 48K SR Blackman3 window no smoothing).
 

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Triode cathode followers is a mess but small signal pentodes is promising. Please Salas, whirl up the dudes to make a decent EF86 CF or something. We really need it.

Staffan

They are a mess only if you don't know how to implement them. The classic example is a 12AX7 as cathode follower in guitar amplifiers. When implemeted properly, they are indispensable at the output side of a line pre. EF86 in that role is unsuitable due to low anode current.
 
They are a mess only if you don't know how to implement them. The classic example is a 12AX7 as cathode follower in guitar amplifiers. When implemeted properly, they are indispensable at the output side of a line pre. EF86 in that role is unsuitable due to low anode current.

12AX7 indispensable at the output side of a line pre, hear hear. Give us the fax in fidelity plz.

Staffan
 
Hi Salas,

It's nice preamp.

I really like 6V6's sound, especially GT with smoke glass. I have some questions for you:

- What is your latest version of schema ? in first page ?
- Did you compare sound quality between 6V6 and DHT, like 26, 31, 71A, 01A, 45... ?
- So far are you still listening this Pre ?

Tks,

QA.
 
I dug up some C3g and C3n. I love those little neaties when removing the cap. They are made for Deutche Post with aditional caps and high specs. Can make a nice follower with 250 on anode and 150 regulated on G2 maybe.



Then I also found some also lovely 6G6G that can be a candidate in the same setup as the 6V6 anode follower. Somewhat lower current but they have a lovely sound.



Staffan
 
I've been reading the whole thread over the last couple of days, and I'm going to have a bash at building one of these.:)

I recently built a preamp designed for a 2A3, with a 6V6 as the anode load. My version used a Russian 6S4S or a 6B4-g which is the 6.3v octal version.

This pre sounds really good, but suffers from a degree of self noise which is annoying.

My plan is to build a prototype on breadboard using an anode CCS for the 6V6 and a slightly modified PSU from the pre I've just built. That should give me a flavour of what it can do.

If all goes well then a PSU with two shunt regulators (one per channel) using an EL34 and an 0D3 will be built and a resistor load for the 6V6. I've got 95% of the bit's needed to build this, so I will start tomorrow and update here on how I'm progressing.

Happy new year to you all.:D