Dr ZWreck is basically an AC30 with a top notch Compressor

[bassman333]

I had the chance to demo back to back the Dr Z Wreck and a UK AC30 Top Boost with a Compressor pedal.

To my ears, and the store workers....it sounded 99 percent alike.

Now I'm not all into circuits and don't know much about anything regarding that, but is there a technical reason why this was my experience?

[Lonely Raven]

Z Wreck is based on the Trainwreck Rocket, which is based on the VOX circuits.

[dartanion]

Yup, based off the Rocket, but with a much different layout and component choice. From what I gather, it may also use a different primary Z on the OT than the Rocket's 4.3k. There also maybe a different selection of laminations as well, which can change the tone significantly. There is nothing wrong with this at all, but if you want an accurate Rocket style amp, the Z is slightly different.

[Cliff Schecht]

I would bet Z went with a 5.2k-ish primary, nicer grain oriented laminates (probably M6 not M4), maybe overrated the thing a bit more and perhaps even found a fancy interleaving method for the windings. All of these little upgrades, while making the OT more expensive, make for a helluva good sounding Rocket!

[rooster]

And I will add that it is typical for the Dr. to use an OT with screen taps. I haven't seen this particualr amp internally but this is always something to consider with the Dr.Z amps.

[M Fowler]

Not sure at all about the OT it looks a lot different in design. It is not UL.

I increased the choke DCR and mA from the Heyboer 158L we use in the Rocket. I used the HTS-159Q 7H 150mA/100DCR. Also the Hammond 159P gets close at 10H/125mA/155DCR

The filtering caps are very low value a softer supply to the preamp tubes and PI. It has the dual HT switching 280v and 260v like Ceriatone does with their Rockit. Speed/Comfort switching. The Zwreck differs from the Rocket layout in that Z adds an additional 220k as a voltage divider at the PI.

The power tubes are NOS Russian 6P14P-EV 7189 EL84 type.

Uses all MF resistors and a 25uf/25v cathode bypass cap on the second triode not found on the Rocket.

For PT and OT use:

PT use HTS-9144 280/250
OT HTS-8093-1 (A-470S) 4K3 or Dynaclone A470S

[crafty1]

[quote="M Fowler"]
I increased the choke DCR and mA from the Heyboer 158L we use in the Rocket. I used the HTS-159Q 7H 150mA/100DCR. Also the Hammond 159P gets close at 10H/125mA/155DCR[/quote]

Mark,

Just curious as to your choke selections for this amp. Both have lower H and DCR to the AC30 and Rocket values?

Rich

[M Fowler]

The henrys isn't as important as the DCR and mA so it can be any choke from 5H to 15H but with DCR as close as you can get to the choke Dr Z uses and has used in many other Z amps.

Mark

[M Fowler]

Hammond 158L 15H 75mA 411DCR

Hammond 159Q 7H 150mA 100DCR

Hammond 159P 10H 125mA 155DCR

I decided to go with higher mA lowering the DCR I know what the Z choke value is but that would require a custom build so I used what is readily available. But I maybe should have used the 159P or ordered a custom choke.

[topbrent]

Z-Wreck innards.

[M Fowler]

Here is mine.

Changed out picture the old one had my bypass caps backwards corrected a while ago. New photo added

Mark

[selloutrr]

I'm almost shocked how simple it is.

[Fischerman]

Nice looking build Mark!

I think I like the rectifier and OT placement better on the Z-wreck. Less 'right-heavy' and easier access to the tube. How much of a difference does the Speed/Comfort switch make? Anyone have a definite preference for Speed or Comfort?

Wonder if there is a specific reason for the ceramic blocking cap but mica treble cap?

[Weathered]

Wow - not a lot of filtering going on in there, is there?

[M Fowler]

No those are 8uf/450v on all three in the pre-amp.

The voltage switch doesn't do anything for me.

It is a good sounding amp. It was dark to begin with but I soon found out that the speakers or cabinet was the problem. I was using a Celestion Blue and 12GH in a very large Marshall closed back cabinet.

With Scum Back M75 or Celestion Vin. 30's the amp is right where I enjoy the brightness.

Mark