6V6 ODS...

[Bob-I]

Bob

Did you use the Bassman OT straight up with the 6V6s? No impedence adjustment at the speakers?

No, I'm using the 4 ohm tap on an ohm speaker.

How many ohms speaker, Bob?

oops, my bad.... 8 ohms

[glasman]

I built a 20W 6V6 for a local player. It uses deluxe reverb replacement iron from CE. I think it came out pretty good. I am trying to get Harry back to house to make a few good clips of him and the amp.

Here is a video of Harry using the 20 watter at a local club. Sorry about the crummy audio quality, first video with a new camera

Harry is a blues rocker so don't look for Robben tones in the way he has the amp set.

http://glaswerks.com/video/harry.wmv

Gary

[glasman]

Forgot to mention, the 20 watt amp uses a 5AR4 rectifier and produces 440 volts. Measured output at clipping was 21.5 watts.

The circuitry was straight D-clone Hybrid_A with obvious tweaking in the power supply (first dropping resistor) and changing the feedback resistor from 4.7K to 5.6K.

Here is picture of Harry's amp. I would have kept if for myself, I really liked this amp. May have to build another.



Gary

[caglej]

Would the Hybrid A bias circuit need to be modified for 6V6's? I was just staring at the deluxe reverb schematics wondering which route to take. I'm definitely using 6v6's, but I'm debating whether to use fixed or cathode bias. If I decide on fixed bias what, if anything, will I need to change?

[Normster]

Wow, Gary! That amp looks and sounds incredible!!!

[glasman]

Would the Hybrid A bias circuit need to be modified for 6V6's? I was just staring at the deluxe reverb schematics wondering which route to take. I'm definitely using 6v6's, but I'm debating whether to use fixed or cathode bias. If I decide on fixed bias what, if anything, will I need to change?

With the 6V6's you will probably have to decrease the first resistor a little to get more range. As I recall 6V6 require about 10 more volts of range. I usually set my bias circuits with of -25 to -70 volts or so, that way I can accomodate virtually any tube. I also use a 15 turn trimmer for the bias adjustment. Take a look at the bias circuit for a Deluxe Reverb, this will get you in the ballpark.

Gary

[glasman]

Wow, Gary! That amp looks and sounds incredible!!!

Thanks Norm, now if I could just play like Harry


Gary

[caglej]

Thanks Gary..........BTW that amp sounds awesome!

[tonelab2]

Gary, Thanks for posting clip and photo.
Great looking and sounding amp. Top quality.

[Darkbluemurder]

My non-HRM modded Deluxe Reverb II uses 6V6s. I like it but I still have not got it to the final stage.

[Normster]

Wow, thanks for bringing this thread to page 1 again! I've been wrestling with building a 6V6 Dumble w/tube rectifier and many of my questions just got answered.

Anyone know what size filter caps I should use with a 5AR4 and 6V6's? I ordered a JJ 32/32 uF can but I want to make sure this isn't going to be too much (with a 64uF first stage). I read in several places that too much filtering and burn up the rectifier tube.

[Smitty]

Norm,

You can run 60uF. I run 50uf (100/100) on all my amps including the ones with 6V6s.

Smitty

[Normster]

Norm,

You can run 60uF. I run 50uf (100/100) on all my amps including the ones with 6V6s.

Smitty

Thanks, Smitty. Looks like I'll have to scrap the cap can idea. Since the 5AR4 is looking for 50uF max, I think 64uf would really shorten the life of the tube. Also, running 2 x 32uF at 500V still only gives me 500V surge protection which is probably not enough. I think I'll just use a couple of 100uF's (or maybe 80uF's) in series to be safe.