Fully Loaded Rocket

[Jackie Treehorn]

Whooo! Home alone and the perfect time to do something stupid like record myself noodling through the EF86 and top boost channels dimed!

All quick and dirty with a strat. My dog became very frightened at the ferocity of the SPL's, so I had to keep it short; would have liked to do a few more takes and a couple with the Les Paul Special but that would be inhumane.

Dimed EF86 improv</a>

Dimed Top Boost Improv

That file has got a comparison of some crunch chords at the end, and the clean-up-ability...

EF86 Rockin' Me

http://www.theinside.net/FLR/Dimed Top ... in' Me.wav

well...can't get those links workin'

[Colossal]

Hey JT,

Haven't seen you around in a while. I always enjoy your clips! So wonderfully elastic.

[Jackie Treehorn]

Thanks, Colossal!

Yes, I fell off the grid for a number of months due to moving and a new day job, unfortunately. Hopefully will be warming up the soldering iron and getting my flux fix again....

[Colossal]

Yes, I fell off the grid for a number of months due to moving and a new day job, unfortunately. Hopefully will be warming up the soldering iron and getting my flux fix again....

I know the feeling man. It is a constant push! I'm going to be moving myself soon. I'm working on four amps right now. Trying to get that done, upgrades to a house, moving the wife who is starting a new job, keeping up with chops...never enough hours

[dvnator]

Sounds good Jackie!

[Mark]

Jackie what prompted the resistor choice?

There are quite a few types in the amp.

[hans-jörg]

Hello,
does a schematic exist from your amp, in the kind you have it now?

Hans-Jörg

[Jackie Treehorn]

Yes, I fell off the grid for a number of months due to moving and a new day job, unfortunately. Hopefully will be warming up the soldering iron and getting my flux fix again....

I know the feeling man. It is a constant push! I'm going to be moving myself soon. I'm working on four amps right now. Trying to get that done, upgrades to a house, moving the wife who is starting a new job, keeping up with chops...never enough hours

Well, best of luck with the move! It is critical to try and keep the balance. I stopped playing for quite awhile, no band, etc. and now I realize that's a mistake; it keeps you sane!

Sounds good Jackie!

Thanks, dvnator! Feb 2009, glad to see you finally posting! Hope to be seeing and hearing some of your amps on the forum!

Jackie what prompted the resistor choice?

There are quite a few types in the amp.

Hey, Mark! Hope you're doing well. It's kind of a long story. There was that clip of a real Rocket on youtube, and it's probably a bad example, but I wasn't really blown away by it. So, I wanted to go more in an ac30 direction, so I went with much lower filtering and a few, hopefully, well placed carbon comps, on the preamp plates of all but v1 of the top boost and EF86 where I used Riken Ohms. The Riken Ohms sound almost as fat as a carbon comp, but they've got no noise which I felt would be advantageous at the start of the signal path. I really like carbon comps in guitar amps, as it's one of the few parts that softens the top without losing detail. They also are somewhat inconsistent, so if I trim out a value with a pot, I can usually find some combination of resistors which will give me the odd value I need. I did that with the mids resistor: it's 11k or so.

I know the polyester caps are more popular with builders trying to cut some top than carbon comps, but having listened to them in a hifi situation, I don't think they do it in a good way; too much smearing of mids and bass. The Mallory PVC's are some of the best sounding polyesters, though. They're pretty clear with just some top end roll off. I would actually say the 716P sounds closer to a Mallory PVC than a Mallory 150 when you listen to them side by side. 716P sounding still a bit better.

So, I was trying to work in a bit of carbon comp fatness, with the Mallory PVC's in the tone stack to get a bit of the polyester thickness in the mids, and basically 716P's and polystyrenes everywhere else. There was a really good electronics salvage/surplus store that had a lot of NOS AB carbon comps, so I did use those in some places, not because I thought they'd have a big tonal impact, but because I think they're good resistors in the particular value required. I tried the Takman carbon comps in some places. They don't sound like the Riken Ohms, though. They don't have the fatness, although they're really consistent. The places with metal film, I think, are just the tremolo. The 33k grid stoppers on the first preamp tubes are the regular carbon films. I think you get a bit more of a complex sound mixing components up, too.

I also ended up bypassing the electrolytics on the cathodes of the power tubes and v1 of the TB preamp with film caps for more clarity. I used the Nichicon Muse series on the cathodes, and they sound really nice. Elna has some kind of audiophile low voltage electrolytic that I tried, but it wasn't so spectacular. The PIO caps, I've done some more experimentation in another amp, are also a good way to soften the top without losing detail.

Hello,
does a schematic exist from your amp, in the kind you have it now?

Hans-Jörg

Hello, Hans! No, I didn't really keep track of it all. This thread is the closest, although I do have layouts and such, for the chassis and boards on graph paper. The switching was kind of complex, both in the relays and in the footswitch. I've got a four button footswitch with three multicolor LED's to go with the amp. I might have drawn something for those parts. Let me know if you're interested in anything in particular and I'll see what I can dig up.

Thanks!

[jul059]

This will somewhat answer the question as to how much can fit into the standard size chassis!

Seems like you were able to fit a lot! My question is : what are the dimensions of a standard size chassis? I am shopping for parts for my first amp and would like to know what is the standard size and what you might think is the minimum for a Rocket single channel.

[Jackie Treehorn]

This will somewhat answer the question as to how much can fit into the standard size chassis!

Seems like you were able to fit a lot! My question is : what are the dimensions of a standard size chassis? I am shopping for parts for my first amp and would like to know what is the standard size and what you might think is the minimum for a Rocket single channel.

17x8x2 is the standard. I got that one from RJ. You could probably go smaller using can caps for the power supply. I like to lay the amp out on graph paper, taking into account the dimensions of the parts, etc. and try a few variations to decide on the layout. You could probably get it smaller if that's your goal.

[njwrecks]

Great looking build- !!!