Mu follower, headphone amp?

[alk]

Hi,

Would someone care to tell me if this preamp is suitable also for headphones?

http://haute.fidelite.com.online.fr/c-DIY.html

The main reason for choosing this schematic is that i have already the valves and transformer. Don't need to be perfect, i don't have the perfect headphones either. Just wanted to know if it would sound ok with headphones, mine are 26 Ohms.


Thanks,

Alk

[fdegrove]

Ola,

Would someone care to tell me if this preamp is suitable also for headphones?

No.

Certainly not with 26 Ohm impedance cans.

You could still use the ECL86s though to make a small amp with the Penthode part of the ECL86 (that's a EL84) in triode mode configured as a Cathode Follower cap coupled into the cans but 26 Ohm would still be a mismatch.

Here's what I would do if I had 4 ECL86s and wanted to build a headphone amp with them:

Triodes (ECC83) in SRPP to drive a White cathode follower consisting of a pair of penthodes in enhanced triode mode (EL84) per channel.
That should work if I'm not mistaken.

Ciao,

[alk]

Hi,

No.

Good to know. Project discarted.

Triodes (ECC83) in SRPP to drive a White cathode follower consisting of a pair of penthodes in enhanced triode mode (EL84) per channel.

About the white cathode follower i was just reading in Tube Cad and i thought, too much trouble to drive my headphones ---best to buy better. I am yet too noobie to implement this idea so.... i'll wait or read more. Thanks for stopping me in what would have been a waste of time. I believe that with a 2V input i don't need a pre, so this would have been for headphones use only.

Cheers.

Saving up for the Lilliput A pity 6080's don't look as good as 300b's though.

[fdegrove]

Hi,

Saving up for the Lilliput A pity 6080's don't look as good as 300b's though.

The 6AS7G is an equivalent of the 6080 and uses a shoulder shape glass:

Cheers,

[alk]

Hi,

That JAN 6080 looks cool....the one in the kit is a GE 6080, which one is better?

The Svelatna looks great also...umm... i have two choices....i'll have both.

Happy to know,

Cheers.

[fdegrove]

Hi,

That JAN 6080 looks cool....the one in the kit is a GE 6080, which one is better?

The JAN should be the more rugged of the two. Whether there would be an audible difference with such a low mu tube I don't know.

The USSR ones may sound different though.

BTW, why don't you use the Lilliput to drive the headphones?
Just use a volumecontrol on the input of the amp and you're done.

QED, the British company reknowned for their range of accessories may still make a switchbox allowing you to hook-up two headphonesets and a set of loudspeakers allowing instantaneous switching between phones and speaker output.

Cheers,

[runeight]

It is my opinion that a WCF makes for a much better OTL tube headphone output stage. It is effectively push-pull, doubling the output current for a given idle current (compared to a follower), gives a very low Zo, and uses a minimum of parts to get more power output than any other type of stage (for a headphone amp).

Check out Headwize for some articles and threads on this type of amp.