Calling DougH Firefly and Mini amps discovered a new tube

[Ansil]

i have been playing with this nice little beast for about a week or two now and i love it.

http://hereford.ampr.org/cgi-bin/tube?tube=6cg7

4watts per triode i belive off the top of my head

Maximum Ratings (Design Center Values)
Each Triode
Plate Voltage ................................. 330 Volts
Plate Dissipation ............................. 4.0 Watts
Characteristics and Typical Operation
Class A Amplifier
Plate Voltage ................................. 250 Volts
Grid No. 1 Voltage ............................ -8 Volts
Amplification Factor .......................... 20
Plate Resistance (approx) ..................... 7700 Ohms
Transconductance .............................. 2600 MicroMhos
Plate Current (Zero Signal) ................... 9 Ma.
Class A Amplifier
Plate Voltage ................................. 250 Volts
Grid No. 1 Voltage ............................ -12.5 Volts
Plate Current (Zero Signal) ................... 1.3 Ma.
Class A Amplifier
Plate Voltage ................................. 90 Volts
Grid No. 1 Voltage ............................ 0 Volts
Plate Resistance (approx) ..................... 6700 Ohms
Transconductance .............................. 3000 MicroMhos
Plate Current (Zero Signal) ................... 10 Ma.


info taken from above link in partial.

i used this in a plug and play replacement for the 12au7 in my beast and love the sound of htis thing. as it will saturate the little fender output transformer real quick.   thought i would pass this along. i guess its similar to the 12hb7

[Doug_H]

;lkj

[beans_amps]

The 6CG7 is a 6SN7 in a 9 pin bottle.

Sean

[Ansil]

coo good to know bean thanks.  

[Johan]

if small powertubes are your thing, you might want to look for EL95..tiny 7pin powerpentod giving about 3watts max and sounding close to EL84...

Johan

[Doug_H]

;lkj

[csj]

I've had really good luck with the 6BM8...it's a triode/pentode. As I recall about 7 watts in push/pull. Good clean sound... a different breakup sound from the EL84. I can't really define it though...it's just different.

[Transmogrifox]

That almost looks like a Heathkit typical wiring job.  I'll bet it sounds like heaven though.

I just got some 7-pin pentodes (4BZ6) and am anxious to find some time to build something with them.

Do any of you have a good recommendation for a solid power supply of about 200 to 300V ? These are very low power tubes, so I am thinking about using them to make a stompbox.

[csj]

It can get uglier...



When I'm finished with this one it will be (hopefully) two amps in one.
2 6L6's on one side and 4 6V6's on the other. Dual rectified. 2 OT's (the other one is an X mount on the top side). Reverb on the 6V6 side. Tremolo on the 6L6 side. The loads will be dumped into a 4 X12" cab with a pair of 12s dedicated to each side. Switching will be a simple A/B box like Doug plans on doing with the Firefly/Herzog. Both amps will be on at the same time and I hope to just toggle between the two. The controls will be separated from it like an old style Premier. That is, if I ever get to it.

IMHO you just can't beat Hammond for cheap good iron. Check their 263_x and 269_x series for the one you need.

[Doug_H]

;lkj

[Regan]

I like p/p myself but I think the next build is going to be like a standard eyelet board, but using circuit board stock so I can etch a ground rail and some simple connections on it without having so many jumper wires(I'm horrible at laying stuff out)
Regan

[csj]

Transmogorifox...
It can get even uglier.  :lol:

I prefer PTP too... it's easier for me to read the circuit and troubleshoot it.  

I promise... no more pics from me on this thread.
Apologize for going OT.

[Peter Snowberg]

:twisted: That's a beautiful pile of chassis there csj.

The 6BM8/ECL82/7591 is a WONDERFUL tube and it's still being made I believe. One 6BM8 and one 12AX7 makes for a smoking little amp with two tubes.

[csj]

Peter,
Yeah, it's amazing how such an ugly tangled pile can be so appealing. Remember when Zvex posted that pic of his breadboard...actually it was about 5 breadboards pieced together. I was staring at that thing so long that I must have lost track of time and my wife came over to check on me because she thought something was wrong with me (maybe there is...I'm starting to worry myself).

The clean sounds on my 6BM8 builds are excellent. The overdriven sound is different... I can't liken it to anything else that I've heard or know of. I don't know quite how to describe it either. I like it alot though. I usually play it without pedals so I'm not sure which pedals would compliment it. You are right though... it is a great tube to work with and yes they are still being made... old stock can be gotten pretty cheaply too. I'm in the planning stages of a quad setup for them right now. I'll let you know how that goes if you're interested. With the triodes built in I won't need any preamp tubes. I'm planning one gain stage, a tone stack driver and a schmitt type splitter into the 4 pentodes. Vox style for the R and C voicing values most likely.


Take care,
Clay