I saw this on the Z Wreck

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Mark
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I saw this on the Z Wreck

Post by Mark »

I found this, I have no idea how accurate it is, but you have to start somewhere. :P
Z wreck Differences to the Rocket are,

1. V1 signal cap to volume pot is 470pf ceramic disc, Treble cap in tone stack is 47pf.
2. The 220k/220k voltage divider exiting the tone stack into the PI.
3. Long tail section - 976k R's instead of 1M, 47.5K R instead of 47K.
4. 250uf bias cap for power tubes.

5. B+ dropping string is paralleled from the output tube screen node to all stages and not in series as is the Rocket.
PI = 27k
CF = 22k
V1 = 27k

Input jack resistor to earth is also a 976k not 1M.
All signal resistors are 1/2w metal film.

The only other obvious difference is the way the CF stage is split between V2a and V2b, Not V1a and V2a.
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Mark Abbott
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Blackburn
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Re: I saw this on the Z Wreck

Post by Blackburn »

Here you go...
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randalp3000
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Re: I saw this on the Z Wreck

Post by randalp3000 »

wow, that looks familiar :wink:
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BLT
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Re: I saw this on the Z Wreck

Post by BLT »

I believe, in some builds, I have seen the other side of V1 grounded.
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BLT
Mark
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Re: I saw this on the Z Wreck

Post by Mark »

Much thanks for sharing those the pictures. They pretty much tell the whole story.

It has me wondering why Ken Fischer would dispense with the Vox power supply and adopt it in the ZWreck?

That does seem odd, as it is one of those decisions which is pretty absolute.
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rp
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Re: I saw this on the Z Wreck

Post by rp »

Looks like KF was trying to make a harder rocking AC30 and DrZ was trying to make a Voxier Rocket :?
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randalp3000
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Re: I saw this on the Z Wreck

Post by randalp3000 »

BLT wrote:I believe, in some builds, I have seen the other side of V1 grounded.
fyi, my original z wreck does not have the bass control grounded. v1 is grounded however also.
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Blackburn
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Re: I saw this on the Z Wreck

Post by Blackburn »

randalp3000 wrote:wow, that looks familiar :wink:
Yeah, some guy sent me that a while back. :P
Mark
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Re: I saw this on the Z Wreck

Post by Mark »

Any chance of a gut shot Randalp?

No is okay as I've heard the Dr-Z army gets a bit annoyed. Personally I think it is your amp and you call do what you like with it. Damned Commie bastards! :lol:
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rooster
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Re: I saw this on the Z Wreck

Post by rooster »

Cool, thanks for this post.

V2B uses a cathode cap, not a Vox thing, but then there's that 220K to ground that mimics the nonexistent Normal Channel.

All polypropolene caps, 715P all?
Most people stall out when fixing a mistake that they've made. Why?
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Blackburn
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Re: I saw this on the Z Wreck

Post by Blackburn »

rooster wrote:Cool, thanks for this post.

V2B uses a cathode cap, not a Vox thing, but then there's that 220K to ground that mimics the nonexistent Normal Channel.

All polypropolene caps, 715P all?
Not sure why you say it's not a Vox thing, having a bypass cap on V2's cathode. Check the Top Boost schem. Also not sure what you mean by the 220k to ground mimicking the Normal channel. From what I remember, that is a mod that Ken would occasionally mention as something available for the Rocket, in conjunction with the bypass cap on V2.

The .022uf pair are 6PS. Compare them to the PI caps.
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randalp3000
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Re: I saw this on the Z Wreck

Post by randalp3000 »

rooster wrote:Cool, thanks for this post.

V2B uses a cathode cap, not a Vox thing, but then there's that 220K to ground that mimics the nonexistent Normal Channel.

All polypropolene caps, 715P all?
Last I heard the good doc ran out of caps and lost his supply so he switched to 150's
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rooster
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Re: I saw this on the Z Wreck

Post by rooster »

Wow, 150s? The white ones are junk in my book.

Oh Blackburn, you are correct about the cathode cap. I have a switch for this on my AC30/Rocket clone and rarely use it - it's the Rocket that doesn't use it. I also have a switch to remove the Normal channel from the circuit - something that would mimic the stock Rocket before Ken suggested the 220k add switch idea to 2Tone. Eh, so I have so many options, I forget. Sorry. 8)

FWiW, I prefer the non-cap cathode on the 2nd stage and the 220K resistor (or Normal Channel) engaged. Which is to say neither the Z-Wreck or the Rocket are this. It's interesting to me that both circuits add gain differently: Ken at the PI, Dr.Z via the 2nd stage cathode cap - and I don't care for the added gain of either. And yes, I have two switches to add or take either way at will.

Have -BTW - you all seen the Derek Ferwerda YouTube video? https://m.youtube.com/watch?v=C1rPY8nLRwE

He says some very interesting things here about his Rocket and Rockets in general. His comments about the LP and the Rocket here: https://m.youtube.com/watch?v=4W48lTmFboM
are very interesting. Particularly his thoughts about an amp (any amp?) and setting it up for the neck or bridge pickup.

Anyway, nice guy, very real. There's even one where he demos something he apparently played for Ken - spontaneously - when he first picked his up from Ken. All interesting stuff.
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Cameron
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Re: I saw this on the Z Wreck

Post by Cameron »

Mark wrote:I found this, I have no idea how accurate it is, but you have to start somewhere. :P
Z wreck Differences to the Rocket are,

1. V1 signal cap to volume pot is 470pf ceramic disc, Treble cap in tone stack is 47pf.
2. The 220k/220k voltage divider exiting the tone stack into the PI.
3. Long tail section - 976k R's instead of 1M, 47.5K R instead of 47K.
4. 250uf bias cap for power tubes.



5. B+ dropping string is paralleled from the output tube screen node to all stages and not in series as is the Rocket.
PI = 27k
CF = 22k
V1 = 27k

Input jack resistor to earth is also a 976k not 1M.
All signal resistors are 1/2w metal film.

The only other obvious difference is the way the CF stage is split between V2a and V2b, Not V1a and V2a.
Whoever wrote that ....is reading the 1m. backwards,.....1m not 976k
Last edited by Cameron on Fri Feb 27, 2015 12:46 pm, edited 1 time in total.
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rp
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Re: I saw this on the Z Wreck

Post by rp »

rooster wrote:Wow, 150s? The white ones are junk in my book
So, you think there's a difference btwn the older yellow ones and the white ones?
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