Ceriatone Forum

Ceriatone => Overtone => Topic started by: billy11 on February 08, 2008, 09:22:58 PM



Title: 6v6's in the Overtone?
Post by: billy11 on February 08, 2008, 09:22:58 PM
HI,

Have any of the Overtone owners tried 6v6's instead of the 6l6's and if so, what do think?

Thanks.


Title: Re: 6v6's in the Overtone?
Post by: ChrisL on February 12, 2008, 12:01:00 AM
No, I haven't tried them in this amp.  But, I did go back and forth between the original 6V6's and 6L6's in my Brownnote D'Lite.  In that case, I was going from a 6V6 optomized circuit to 6L6. 

Just a heads-up (for everyone thinking of trying this) about swapping.  I haven't taken a close look at Nik's OT for the Overtone but I'm guessing it doesn't have dual Primaries....I'll check when I get home.  The pair of 6L6's want to see a primary impedance of around 5K and conversely a pair of 6V6's...8K.  Therefore, it isn't a simple case of re-bias and play.  You have an impedance mismatch BUT because there are 4,8, and 16 ohm secondary taps there is leeway to better approximate the correct primary impedance. 

On the D'lite you have an 8K Pri OT  (6V6) that you want to "knock down" to 4 or 5K for 6L6's.  To do so just re-label the secondaries as 2, 4 and 8 ohms instead of 4,8, and 16.  I'm certainly no EE so correct me if my logic is wrong but 6L6 to 6V6 should be the opposite....8, 16, and 32 ohm instead of 4, 8, and 16.   All this being said, a 100% impedance mis-match can sound great and the OT should be able to handle it. 

Discuss.... 


Title: Re: 6v6's in the Overtone?
Post by: max on February 13, 2008, 11:57:32 PM
I have no expertise but would be interested in how to do this if possible, I know you can go between 6l6 and el34 if I am correct but to be able to use 6v6 would be awesome. Not knowing much can you use kt66 in the overtone.
And a tip of my hat to you tech guys who build them yourselves.
Thx
Burnie


Title: Re: 6v6's in the Overtone?
Post by: DrBluzeman59 on March 12, 2008, 12:10:02 AM
 I am wondering if Nik could build this for 6V6, maybe using the OT/ PT from a Blackface or 5E3 Deluxe ?


Title: Re: 6v6's in the Overtone?
Post by: wyatt on March 13, 2008, 11:26:05 PM
Just make sure the plate voltage isn't much more than 425VDC, which is the maximum for most 6V6's, and actually too much for many (the JJ's might handle more, their really small-bottle 6L6's). 


Title: Re: 6v6's in the Overtone?
Post by: johnnymac on May 20, 2008, 09:47:34 PM
You can swap 6v6s for 6L6s as long as you adjust the bias. The impedance mismatch doesn't amount to much. I use 6v6s in my ots with switched/ fixed cathode bias (500ohms/10 watts) and it sounds great. I've done this swap with Bassmans, Twins, Bandmasters, a Blues Deluxe, and I've even run them in my Super Twin. As long as you get the bias half way close you'll be fine. Try it! Use good quality tubes that can handle the voltage. My Deluxe Reverb runs the plates at about 420 volts DC. you don't want to go much higher than that so I hear. i've run 6v6s (JJs) at 440v all night however, and nothing happened.