Rocket w/ EF86 channel worthy, or just a DC30.

[chopstuck]

I have had an epiphany with the Sting/Stang Ray. Very nice sounding amp with a Tele. It stays on the "edge" and gets some good "grit" with a single Celestion alnico Gold. Now I love my 15w Lightning and Spitfire clones as well as Dart's ef86 lite, but I want to combine the "Rocket with the Ray" into one amp. Kind of a DC30 morph.
Could the hybrid still sound removed enough from the Matchless to make it a worthy build ? Could it still retain each amps identity/ voice since the power sections are so similar ? I plan to use a TS PT and Hammond choke and possibly a Dynaclone or TS OT.
Any opinions ? The EF preamp seems quite compact and space shouldn't be an issue.

[dave g]

Does the Rocket sound far removed enough from an AC30 to make it a worthy build?

I'd say go for it. You'll probably like it. Keep in mind, though, that the amp will probably have less gain than either a Rocket or a Stang Ray due to the tonestack loss. You could bias the phase inverter a bit hotter to make up for the lost gain.

[chopstuck]

When combining the preamps with their own tone stacks, EF86-Zodiac and 12ax7-Treb & Bass, Do you lose gain as the active channel gets loaded down by the unused channel ? or lost in the mixing resistors ?

Ideally I wouldn't want to have to hard switch between channels but I would if it was the only way to preserve the character of each preamp.

[dave g]

Whoops, didn't see the part about the multiple channels. I thought it was just an EF86 front end.

The loading is all going to depend on how you tie the two channels together. How were you planning on doing it?

[chopstuck]

That was was going to be my question. Simple would be best- mixing resistors, but would it isolate the channels well enough ?

[M Fowler]

Chopstuck,

I also love my Stangray for its clean with the open back 212 blues. I also like my Spitfire clone for its chimey yet has an ability to get great crunch in an amp called 15 watts but with my 18 watt trannies I think it is putting out more watts.

I have been reviewing the Stangray layout and schematic as well as ceriatones layouts trying to figure out exactly what I want. I notice that most are using the EF86 with 12ax7 and I think I should run another 12ax7 (three tube preamps) for more gain. But I still want it to be able to have a clean head room before kicking in the crunch. So maybe just add a VVR and be done. Otherwise will be running the vol knob all night.

Mark

[chopstuck]

Well I just finished a budget special- a half strength St*ng ray. My Pinto-ray.
I cobbled together an old Zenith extension cabinet chassis and a big Bogen 7868 OT. It sounds great, (after I remembered the conjugate filter). Totally different from my Spit, Lightning and my EF86 powered 18 watt lite. The PT is too hot at 350-0-350 but I cathode biased the el84s with a shared 300 ohm Rk. I hope to do a little voltage reduction soon. I tried a few OTs and the Bogen just spanked all the rivals. Big frame unit.

It sparkles without the hash. Stays clean up to 1:00-2:00 and just a little bit edgy after that. I suppose I could change the PI but I love the clean sound so much more than a Spit. Much more character.
I think I like prototype enough to go for a full on 30 watter with proper Heyboer iron.

I'm going ahead with the Rocket-Ray idea. The way I see it, it adds maybe $10 worth of parts, some head scratching..... and $25 tube.

[M Fowler]

Chopstuck,

Keep us posted on the Rocket-Ray. I haven't started yet too busy buttoning things up on another build.

Mark

[chopstuck]

Well I opened up the Pinto-Ray and changed the 7.5k grid stoppers for 1.5K and... what a difference. I guess it was biased cold with the 300 ohm Kr but the increased drive helped warm it up a lot.
I have also finished my 4 holer in a Layfayette chassis and am very happy. It gets a little weird and bass farty on breakup but I attribute that to old power tubes and/or inadequate filtering. Should be easy enough to remedy.

[M Fowler]

You may need to go with adjustable bias instead of cathode unless it is working fine now.

Glad you got the amp together.

Mark