Wanting to build another Rocket: Rocket or ZWreck?

Express, Liverpool, Rocket, Dirty Little Monster, etc.

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fish22
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Wanting to build another Rocket: Rocket or ZWreck?

Post by fish22 »

Hey everyone, Im new around here. I'm still a noob at amp building so forgive me for sounding as such...
Thanks to this greart forum I just finished up an RJ rocket and am really please with it, as is the friend I built it for. I would like to build another for myself now. The Zwreck has been at the top of my list for awhile now and realizing that it is basically a Rocket, it has got me thinking... should I do a Rocket or Zwreck?

Tone wise, I really like the rocket, but things I MIGHT change would be:
-a little less bass (.022uF coupling caps?)
-maybe a little less gain (or more headroom?)
-more sparkle
-maybe a little more chime (a la vox clean, although I realize the Rocket can chime)

So... should I start with a Rocket board, build it with Zwreck values and compare my 2 amps? Should I just use different values on the Rocket to tailor it to what I want?

I'm also curious what people hear to be different between the two from people who have built or own both. :D

Any thoughts or advice would be greatly appreciated.
Cheers

Wyatt
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JoeCon
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Re: Wanting to build another Rocket: Rocket or ZWreck?

Post by JoeCon »

Fish

After my Rocket I went with the ROCKSTER the octal brother to the Rocket and WOW what a great amp.
And I believe RJ can help out with that build too.
I went with KT66 tubes and really like it...

HTH...
In theory, theory is the same as practice. In practice it's different.
Zippy
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Re: Wanting to build another Rocket: Rocket or ZWreck?

Post by Zippy »

Path 1: Build the KT66 Rockster. Like the Rocket, it's a great amp -only MORE. Don't forget to add the MID knob.

Path 2: Build the Rocket and make incremental changes after you finish it. That way you'll learn the effects of your changes and be less the noob when you're done.

RJ has accumulated a book o' tweaks from all his builds on the Rocket platform. I've never heard a bad one, only some that sounded better than others.

Enjoy!
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JoeCon
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Re: Wanting to build another Rocket: Rocket or ZWreck?

Post by JoeCon »

Zippy,

You got that right about tweaking the Rocket. And most of those also work great on the Rockster.

One thing I really like about the Rockster is the octal socket gives you a variety of output tubes to choose from and find the type that gives you the sound you want. For me KT66's just sing in that amp, but I'd like to build another tailored more for EL34's.

You can't go wrong with these builds...
In theory, theory is the same as practice. In practice it's different.
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RJ Guitars
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Re: Wanting to build another Rocket: Rocket or ZWreck?

Post by RJ Guitars »

Zippy wrote:Path 1: Build the KT66 Rockster. Like the Rocket... only MORE.
JoeCon wrote:... For me KT66's just sing in that amp...
IMHO - The KT-66 Rockster is really the ultimate Rocket amp... also I did build one with a set of 5881's that sounded quite nice!

However, for the addiction to run it's full course, you'll need to build an Express just so you can say "Wow, that thing is really loud... and the band will tell you how distinctly it brings out every mistake you make. There is no hiding using one of these amps!

After that then build the Liverpool so you'll know what everybody means when they say " this one has really got an attitude" and yes - it's also very loud!

If your really feeling like the complete set you can do the Songwriter, but I don't think that one is for everybody.

After that you've got your reverb and lower power options... unless you want to press the issue and do the 80 watt versions.
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JoeCon
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Re: Wanting to build another Rocket: Rocket or ZWreck?

Post by JoeCon »

RJ

Getting outta control!! LOL...
Sir, I did build a 2 EL84 Liverpool that's a great lead amp and way loud. So I think an Express is not for me. But I'd like a cathode biased EL34 type amp so as I said a Rockster with a few tweaks of course.

And proof that the Rockster with KT66's is a nice amp, our keyboard player came up to me after a set and said.." man, your amp sound great." And I've been thru Mesa's and Marshall's and modeling amps and never a word till now!!
That amp's a keeper!
In theory, theory is the same as practice. In practice it's different.
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M Fowler
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Re: Wanting to build another Rocket: Rocket or ZWreck?

Post by M Fowler »

I gigged many years with my reverb rocket head with either el34's or 6550's through a 412 with Celestion vintage 30's.

Not a very attractive looking amp but sure makes up for it in tone and fun factor. Red Dr Z Route 66 cab, foot switch boost, sharpie faceplate. Such a pedal friendly amp.
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JoeCon
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Re: Wanting to build another Rocket: Rocket or ZWreck?

Post by JoeCon »

Mark

Ok so I want to build one any tips to make the EL34's work good?? Change the PI values for more output to those tubes?

On my Rockster I upped the first coupling cap to .001uF and the PI coupling caps went to .022. Sounds great...

Thanks...
In theory, theory is the same as practice. In practice it's different.
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M Fowler
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Re: Wanting to build another Rocket: Rocket or ZWreck?

Post by M Fowler »

I've built them with both .1uf/600v coupling caps and .047uf/600v coupling caps either one works well.

I'm sure the above amp use .047uf OD
joeboo88
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Re: Wanting to build another Rocket: Rocket or ZWreck?

Post by joeboo88 »

Hi Mark, what type of trannies did you use? That amp looks great
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rp
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Re: Wanting to build another Rocket: Rocket or ZWreck?

Post by rp »

Tone wise, I really like the rocket, but things I MIGHT change would be:
-a little less bass (.022uF coupling caps?) -maybe a little less gain (or more headroom?) -more sparkle -maybe a little more chime (a la vox clean, although I realize the Rocket can chime)


Maybe lowering the filtering to Vox style for the first. Maybe a proper Vox OT (maybe Mercury) for the chime. Sparkle can often be just a few pfs somewhere.

Is the Rockster just a tube swap on a Rocket? I'm curious too if the PI is changed. Are KT66 easier to drive than EL34s or 6L6s? Maybe that's the reason for the synergy?
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M Fowler
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Re: Wanting to build another Rocket: Rocket or ZWreck?

Post by M Fowler »

joeboo88 wrote:Hi Mark, what type of trannies did you use? That amp looks great
Thanks used:
Heyboer HTS-5199 300mA 300-0-300
Heyboer HTS-5200 5K2 OT 4/8/16 50w rating
Hammond 158L choke
Fender reverb driver

I've also built this amp with Marshall JCM800 transformer set and with Fender 50w Bassman set too.

For increased wattage use 325-0-325 or 350-0-350 transformers change the dropping string to suit preamp voltage needs. The stock Rocket is lower voltage in V1 & V2 then say a Dumble ODS or typical Fender blackface.

Also, go with fixed bias rather then cathode bias. I've built Rockets from 18w to 100w with no change to board values but experimenting would be a good idea.
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JoeCon
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Re: Wanting to build another Rocket: Rocket or ZWreck?

Post by JoeCon »

rp

Looks like the PI is the same for the Rocket and Rockster.

Also I used NO choke on mine, 285-0-285 200mA Edcor PT and a 5K 30 watt Edcor OT 4/8/16. Also SS rectification.
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Re: Wanting to build another Rocket: Rocket or ZWreck?

Post by RJ Guitars »

rp wrote:...Is the Rockster just a tube swap on a Rocket? I'm curious too if the PI is changed. Are KT66 easier to drive than EL34s or 6L6s? Maybe that's the reason for the synergy?
On the first Rockster I initially planned it to use 6V6GT's. I was aware of "Normsters" 6V6GT Reverb Rocket (he did that before me) and although didn't really follow his build I also didn't avoid looking at along the way.

When I was finished with the amp it sounded good but maybe not as good as my EL-84 Rocket. Soon afterward began to experiment with other output tubes and found the KT-66's sounded a lot like the EL-84's but they seemed to have a little "More" of everything (including volume). I didn't do much to optimize that configuration and most builders since have not changed it much either.

With the octal output tube there are a ton of options. I did try EL-34's but did nothing special to optimize them. Because the typical Rockster uses cathode biasing it would likely need some tweaking to be ideal - I think there is a matchless circuit out there as well as a Vox that might serve as a guide.

I'll also mention again one of Zippy's early observations as we built the original Rockster - that circuit starts to look like an old Bassman once you get the octals in there.

As far as transformers I'd say you have a big set of options in both PT's and OT's. It's never gonna be a high gain amp like an Express but it is still pretty loud. To get useable distortion in small venues it will either take an attenuator or a pedal... these are very pedal friendly. For the OT I'd tend to suggest the 7-layer Dynaco winds to add a little more flavor to the sound.

With a higher voltage PT, Stiff power supply, and some 6550's or KT-88's this might not be a bad bass amp?
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M Fowler
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Re: Wanting to build another Rocket: Rocket or ZWreck?

Post by M Fowler »

The rj Reverb Rockster combo I built supplied by rjguitars with Edcor transformers sounds great and I found no difference in tone from my Normster.

I would get a kit from rjguitars and build a nice octal Rocket with or without reverb and you will have a great practise or gigging amp.
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