Cow Tipper Clone

[jon]

Thought I would post some shots of my recently completed Tipper. It really sounds amazing. Really nice cleans till about 11 o'clock on the dial then nice drive into crunch. I used a Scavenged Stromberg Carlson PT our of an AU-57 and the OT is a Dynaclone A470.

[IMG:800:600]http://i82.photobucket.com/albums/j250/Jhtjon/Amps%20and%20Stuff/IMG_2431_zps2f5fa0fb.jpg[/img]

[IMG:800:600]http://i82.photobucket.com/albums/j250/Jhtjon/Amps%20and%20Stuff/IMG_2430_zps9110c344.jpg[/img]

Now all I need are some good tubes for it as I am currently running my shop beaters.

Any suggestions. on power tubes.

[dcribbs1412]

Congrats Jon
nice looking build.
not sure what circuit is the Tipper based on?
Bassman?

Darin

[jon]

Super Reverb

[Leo_Gnardo]

Any suggestions. on power tubes.

RCA 6L6GC Blackplate, good used ones even (NOS you'll have to sell your car to afford) always sweet and robust.

If your B+ is say 450 max, might think KT66 if they'll fit in the box. Big bulbs. Even the China made ones are good. I wouldn't press too much B+ on any of 'em though.

[LeftyStrat]

If you're looking for new tubes, you might want to try the JJ 6CA7. It's sort of a cross between an EL34 and 6L6.

I noticed you did the coiled wire thing like the originals. Have you ABed that with straight wire. I'm just trying to understand what the purpose of that is.

[jon]

If you're looking for new tubes, you might want to try the JJ 6CA7. It's sort of a cross between an EL34 and 6L6.

I noticed you did the coiled wire thing like the originals. Have you ABed that with straight wire. I'm just trying to understand what the purpose of that is.

HMMMMM

Interesting. I am going to try a pair of KT66's in there since I have them I also will prob. try a set of 6550's as I have enough juice to run them.

[Leo_Gnardo]

I am going to try a pair of KT66's in there since I have them I also will prob. try a set of 6550's as I have enough juice to run them.

Despite their huge bottle, KT66 tend to turn out low power figures. But the tone is glorious.

6550 draw @ twice the filament current of the 6L6 tube family. If your PT can handle it - worth a go.

6CA7 may require pin 1 to be grounded similar to EL34. If there's a G3 suppressor grid, and it isn't addressed properly, tube life will be very short. Go ahead ask me how I found out... yes the hard way. With some very nice Siemens EL34 @ 1990. Don't want anyone else to wreck perfectly good tubes by accident.

Also 6CA7/EL34 draw about 50% more filament current than 6L6. Whether you're trying them or 6550, monitor your filament voltage and if it drops much below 6.3V you may want to rule those tubes out. OTOH I've put EL34 into lots of old Fender amps and haven't had a PT melt down yet. Usually get a power increase and a dab of Marshall like tone.

What is the B+ in your Cowtipper?

[Colossal]

That's a beauty John! Even better than the real thing.

[vibratoking]

Jon, that's a great looking build! Congrats. Care to post the schematic that you built from? I have an original 65 SR. Quite a few years ago I swapped out the blue molded caps for orange drops thinking it might make an improvement. It didn't. I tried 715s and 6PS...Good thing I saved the original caps. They are back in there and the amp sounds great.

I am wondering why the Tipper sounds good with orange drops? That's the reason that I am asking for the schematic. I'd like to get a better understanding of how that circuit is designed. Or is it exactly a SR?

[jon]

I am going to try a pair of KT66's in there since I have them I also will prob. try a set of 6550's as I have enough juice to run them.

Despite their huge bottle, KT66 tend to turn out low power figures. But the tone is glorious.

6550 draw @ twice the filament current of the 6L6 tube family. If your PT can handle it - worth a go.

6CA7 may require pin 1 to be grounded similar to EL34. If there's a G3 suppressor grid, and it isn't addressed properly, tube life will be very short. Go ahead ask me how I found out... yes the hard way. With some very nice Siemens EL34 @ 1990. Don't want anyone else to wreck perfectly good tubes by accident.

Also 6CA7/EL34 draw about 50% more filament current than 6L6. Whether you're trying them or 6550, monitor your filament voltage and if it drops much below 6.3V you may want to rule those tubes out. OTOH I've put EL34 into lots of old Fender amps and haven't had a PT melt down yet. Usually get a power increase and a dab of Marshall like tone.

What is the B+ in your Cowtipper?

My B+ with a SS plug is around 460V, an 415V with a 5U4GB.

As far as 6CA7/EL34's I usually install a Raw Bias supply to help prolong tube life. Look at an old Traynor for reference.

As far a filament current goes I should be fine the Stromberg Carlson AU-57 which donated the PT had a whole slew of 12AX7 tubes so I've got some extra room. Additionally, I've got a second 6.3V line should I need it.

[jon]

That's a beauty John! Even better than the real thing.

Thanks!

I was actually going to add some hot glue and silicone to complete the look of an original.....


NOT!

[Leo_Gnardo]

What is the B+ in your Cowtipper?

My B+ with a SS plug is around 460V, an 415V with a 5U4GB.

As far as 6CA7/EL34's I usually install a Raw Bias supply to help prolong tube life. Look at an old Traynor for reference.

As far a filament current goes I should be fine the Stromberg Carlson AU-57 which donated the PT had a whole slew of 12AX7 tubes so I've got some extra room. Additionally, I've got a second 6.3V line should I need it.

KT66 will love working with a 5U4 I'll bet!

Traynor ran the G3 suppressor to the negative bias voltage - seen that, never done it, will have to give it a go.

Good to have all that extra filament current. No worries - looking forward to your review of various output tubes with the Cowtipper.

[jon]

What is the B+ in your Cowtipper?

My B+ with a SS plug is around 460V, an 415V with a 5U4GB.

As far as 6CA7/EL34's I usually install a Raw Bias supply to help prolong tube life. Look at an old Traynor for reference.

As far a filament current goes I should be fine the Stromberg Carlson AU-57 which donated the PT had a whole slew of 12AX7 tubes so I've got some extra room. Additionally, I've got a second 6.3V line should I need it.

KT66 will love working with a 5U4 I'll bet!

Traynor ran the G3 suppressor to the negative bias voltage - seen that, never done it, will have to give it a go.

Good to have all that extra filament current. No worries - looking forward to your review of various output tubes with the Cowtipper.

When you do it you will need to re-Bias. It changes the operation of the tube considerably.

[Reeltarded]

That's a beauty John! Even better than the real thing.

Thanks!

I was actually going to add some hot glue and silicone to complete the look of an original.....


NOT!

LOL

Looks great!!

[Leo_Gnardo]

As far as 6CA7/EL34's I usually install a Raw Bias supply to help prolong tube life. Look at an old Traynor for reference.

Traynor ran the G3 suppressor to the negative bias voltage - seen that, never done it, will have to give it a go.

When you do it you will need to re-Bias. It changes the operation of the tube considerably.

Thanks jon I did not know that. Good tip, from a Cowtipper builder!

Just fixed up a MkII Traynor YBA-1A with KT88. Had to dial the G2 down a lot to keep the screen grids happy. Came out pretty dam' well. Hope the customer likes it as much as I do. Traynors were built tough as a brick outhouse back then.