trinityamps.com

Looking for some feedback on this. Anybody done it yet? willowhaus??

As a start, I would take the setting for 6L6 and use the 2.5K primary tap on the OT.

Then calculate the power dissipation.

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Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

My kit has been waiting for me to have some time... I actually may have some now, though.

I was leaning towards the KT66, since it's gotten so many raves around here. Would be cool to make it switchable though - I believe we'd talked about that when I ordered the kit?

Anyway, I'm going to be off work for awhile so I might just have the time to get started.

you should be able to switch between KT66 & EL34 cathode resistors pretty easily. but you will need to also switch the OT impedance for EL34 to the 2.5K

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Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Will have to give that some thought...

If you use a DPDT switch, you can use one gang to switch the cathode resistor value, and the other gang of the switch to change the OT primary tapping. And remember never to flip the switch when the amp is powered up.

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Great tones come in small glass jars!

A mini-toggle with a locking lever might be a good idea for these tube swappable amps, crunch/munch switching, etc. Anything you don't want to switch by mistake with the amp on.
With this type you need to pull the lever up to actuate it...
http://parts.digikey.ca/1/1/473276-sw-t ... l206n.html

We used to use a C&K version.

Joe G

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Some assembly required,
Brain sold separately...

Forgot you'd mentioned this, I posted another thread about it...good idea! I believe I can do this...

willowhaus did you accomplish the el34 mod?
what resistor value?

In process - I have an EL34 tube en route (I have a KT66 and a 6V6 right now). If no one's worked it out yet I'll test & see what I come up with. I believe zaphod said that the 6L6 value should be pretty close...

It is close enough that I had no issues with running an el34
KT88 I am using another 750r in parallel for 375r
Works not bad but probably could use some tweaking.

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Fantasy Noise is what my shop of dreams is called and was the only way to beat my addiction, like many here I suffer from G.A.S.


Tele's make the best noise

Got my tube today, a Russian Tung-Sol EL34B. I calculated the following with the stock 6L6 setup, only switching the OT tap:

cathode volts: 25.8
screen grid voltage: 3.25
plate volts: 329

cathode current: 0.080625
screen grid current: 0.00325
anode current: 0.0774

watts: 25.46

I believe that's pretty darn close, yes?

Incidentally...this little beast sounds SWEET with the EL34! The KT66 has more of that American-type "edge" to it, but this...this is smooooth. Me likey!

changed the 1 meg resistor
and then the el34 and WOW!
BIG change with the el34
maybe its the red wine, but it is sweet with my G&L ASAT and single 12" WGS Veteran 30!
I'll try a 60's Mullard el34 next but not sure how much more improved it can get.
m

Awesome!!!

I love EL34s in this amp.

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Great tones come in small glass jars!