I've started again.....Rocket

[norburybrook]

thanks Mike, couldn't have done it without you Hope yours turns out as good as mine I'm really pleased with the result.

I've missed Martin Manning's input on this build, however that can only mean I'm actually getting better




Marcus

[martin manning]

Hey, you seem to be doing just fine! In fact, I'm inspired to get back on my Rocket Reverb project! Good to hear the EH and JJ tubes worked out too.

[M Fowler]

Oh you guys and your Rockets

Nice job.

[stretch2011]

I've had the itch to build my first rocket for the last year. And this REALLY makes me want to scratch it!

Nice work and a beautiful cabinet!

[norburybrook]

thanks guys

been breaking it in today. It's paired with my dumble 2x 12 cab that now has vintage 1979 Celestion 12-65's in it which seem to suit the rocket well, I've a feeling alnico's would have more chime though.

It's got an amazing overdrive when you turn it up, really , really rich and JTM like . Maybe it's because my voltages are higher than a standard rocket and it's going though G12 65's

It doesn't have a lot of fully clean headroom but I'm a fan of that slight breakup sound anyway, and it's a sound that Dumble's don't seem to do very well. I suppose its a classic cathode biased, valve rectified , non master volume signature sound.


I wont need to put the heating on in the studio this winter, boy those EL84's pump out some heat



Marcus

[BLT]

Any chance you might post your voltages?

[M Fowler]

You can reduce the 220k plate resistor for 120k and have less gain, the amp still gets the gain but at about 1 o'clock instead of 3.

[norburybrook]

You can reduce the 220k plate resistor for 120k and have less gain, the amp still gets the gain but at about 1 o'clock instead of 3.

Mark....Isn't that more gain? 1 instead of 3?



Marcus

[M Fowler]

1 o'clock = 6 or 7 on dial verses 3 on the dial, sorry about the confusion.

[norburybrook]

no problem will the overall level stay the same though? I mean will it just give me more clean headroom or will it just be the same but the volume knob will be at a different position? if you see what I mean.


Marcus

[M Fowler]

One resistor give it a try. You could increase voltage slightly to that preamp tube along with the 120K plate for more headroom.

I rarely have 220k plate in my Rockets.

[guitarmike2107]

You would easily fit a small toggle switch to switch a 220k resistor in parallel with the existing one, that way you could have the best of both worlds.

[norburybrook]

Might be worth a try.

Just got back home this evening to a little package form the Ukraine.....


Russian Military spec valves



Marcus

[norburybrook]

Well, fitted the Russian Military valves...............................


I can't hear any difference Honestly , don't waste your money, just get JJ's they sound exactly the same at half the price.



Well at least I have a set of spares now.


Interesting note that the 100k carbon resistor in the middle of V2 went tits up today before I'd changed the valves. Never had a bad resistor before, anyway swapped it out for a metal film and all is well.

Marcus

[BLT]

They may make a difference down the line, although I have not built an EL84 amp that didn't like JJs.