Dr.Z For All

Tube or solid-state, this section goes to eleven!
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DougH
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Post by DougH »

I guess what happened, was originally when the amp came out I was really impressed with the sound of it. When I found out what was in it I mistakenly thought it was fairly unique, not the typical fenmarvox derivative. The reason I treated it gingerly (via not originally posting the Hwy89) was because I respected the builder and mistakenly assumed he designed it. I knew the builder didn't smile on schems being distributed so I respected his wishes, that's all there was to it.

I know now it's really convoluted to worry about a hobby pedal schematic that, except for some very high level building blocks, bears no relation whatsoever to this amp. I mean, what a stretch, give me a break, Doug... :roll: :oops: The amp was just an inspiration, but at the time I erred on the side of being anal with this 'ethics' stuff. Nowadays I realize that kind of "protectionism" is really ridiculous and none of it matters anyway. Everything comes from everything else and it's the perception of quality, bling, and mojo that sells musical equipment, esp boutique- not the electronic circuits inside or any design elegance. That was just a naive fantasy of the past. I'm not being cynical here, I'm truly being realistic. The electronic circuit designs that make up this stuff are just commodities. They are a dime a dozen, not even worth the price of a single resistor. That's actually true, it doesn't take a business wizard to see that.

I mean, they may be responsible for 99% of the tone, but that's not important compared to the kewl construction techniques, type of wire, having the "correct" mojo components, and the builder being able to talk the talk and shoot the sh*t with the proper buzzwords and fluff on his website, as well as having some kewl endorsements from some hip musicians. (Okay, now I am being a little cynical...)

Anyway, getting back to "protecting" the schematic- What was there to protect anyway? The amp was completely based on public domain information. It was all out there all along. Didn't have to reverse anything, break through any goop, have meaningless arguments about ethics of reversing in web forums- it was all out there already, just ready for the picking. Knowing what I know now, I would have posted the HWY89 on a web site from day one and not looked back. There was no reason to do otherwise.

It's interesting you brought up the hwy89. I completely forgot about it until right now. It had nothing to do with my orig post. I'm just weary of boutique hype and lost respect for another boutiquer, that is all.

I don't view this the same as dismissing any dual-opamp-with-clippers as TS clones. It's not that general of a case. It's this basic circuit topology, which is pretty complete minus the tone stack, that I mistakenly thought was unique. Sure he had to tune/tweak to get it to sound good for what he intended. But every amp builder has to do that. If they can't do that, they shouldn't be in the business. I don't view that as a special talent, unless it's done per customer, like HAD and KF.
"You have just tubescreamered or fuzzfaced yourself " -polarbearfx

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jaxx
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Post by jaxx »

hi guyz!!!


i watched schematics posted in dr z.zip

for example, in stang rxy files (''StangrayBOM.jpg''+''StangrayLayout1_1.jpg'') resistors and some caps are different if you look to the ''ac30-4ef.jpg''. :hmmm:


in stangrxy bom are explained five 1,5k res that does not exist in layout and in the other scheme. :scratch:


has anyone photos of a original stang layout???

thanxx

:popcorn:

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madditch
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Post by madditch »

The 1,5K resistors are the value of the grid stoppers in the AC30/4 the Z uses 7,5K. I have tried both in my build and have settled on the 1,5K which seem to add just a little edge to the tone, barely noticeable. I build it according to the values in the layout, and it sounds like it should, I would suggest using 1K screen resistors instead of the 100R ones, or what I did was add a shared 1K screen resistor into the 4 individual 100Rs. The rectifier should be a 5AR4 not the 5U4GB as shown in the layout.

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jaxx
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Post by jaxx »

thank you Madditch for response,

take a look to the R9 in the layout connected to C9, in stank-ray scheme there isn't like there is not send/return.


if you look also in layout R35 10k and R1 27k are in series, not in st-ray scheme.
in layout only R35 is connected to C2(F&T 50+50uF), in the other schematic either are connected to C2.


what's the right?

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schtaf
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Post by schtaf »

Hey Everybody first post here today.

I was wondering if anyone has seen or knows of the differences between this older combo and Z's new Mini head. The new one has built in attenuation and I was wondering if it would be as simple as adding an L-pad between the output and speaker, like a powersoak or whatever its called.

Thanks!

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madditch
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Post by madditch »

jaxx, the schematic is not correct for the stang, it looks like a cross between the AC30/4 and the Mazerati GT. Just follow the layout, that is correct, I left the effects loop out, it sucks anyway. You can leave the R11 grid stopper in or just connect the wiper to C9.

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SPeter
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Post by SPeter »

Hi,
The link for the ZIP file of schematics does not work!Could someone of you if possesses it to be so kind to send it to my E-mail address:peterdavidoff@hotmail.com

Many thanks in advance!

Peter

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jaxx
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Post by jaxx »

hi guys,


madditch, how sound your stang clone? it's like the original?
if it is, i found my new project!!!


for power and output tranforsformer is not a problem to find a good ones, but for choke, how many henries are the stang one?

i know that dr. z transformers are made by cintran.


thanxx

:thumbsup

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madditch
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Post by madditch »

jaxx wrote:hi guys,


madditch, how sound your stang clone? it's like the original?
if it is, i found my new project!!!


for power and output tranforsformer is not a problem to find a good ones, but for choke, how many henries are the stang one?

i know that dr. z transformers are made by cintran.


thanxx

:thumbsup
I haven't compared them side by side, but from the samples I've heard it sounds pretty close. Just use the VOX AC30 transformer set and choke.

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schtaf
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Post by schtaf »

So has anyone built a Mini Z here? Any comments, build reports, words of advice, cab/speaker suggestions? Thanks!

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invalidcd
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Post by invalidcd »

schtaf wrote:So has anyone built a Mini Z here? Any comments, build reports, words of advice, cab/speaker suggestions? Thanks!
I have built the mini z , i use a one 12" speaker or a two twelve speaker" cabinet , to me its the loudest single ended amp i've ever heard, it sounds like early ZZ Top not the cheesy 80's ZZ Top but the 70's ZZ Top.
I would recommend this build its super easy. One thing i will say is, it is a gainy amp so to achieve a nice clean you have to use your guitar's volume knob. Hope this helps

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Duke Lion
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Post by Duke Lion »

Is there any chance of getting a Maz-18 junior NR layout? :P
I see that there's a schematic for the reverb version and there's pictures of both amps' guts, so wouldn't it be possible for someone to whip up a layout for the NR version?

The amp looks very simple to me, and I'm 100% sure I could put one together if I had a layout :)

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jaxx
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Post by jaxx »

take this gift guys,


http://images.google.it/imgres?imgurl=h ... G%26um%3D1


here you can find a lot of Maz 18 photos, look also at the dr.z.zip files and try to do a layout.


i'm a lot interested to do a Maz Nr, i'm also tring to get a true layout from these files,
later we can compare our to be sure that we have done is correct!!!



:thumbsup

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jaxx
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Post by jaxx »

are you sure that resistors 10K and 27k in mazerati gt power section are correct?


looking to that photo i'm not sure that colors are correct for 10K and 27k values...
10K may be correct but not 27k..


madditch do you also build mazerati amp? what do you think about?
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MazeratiGTUnten.jpg

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jaxx
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Post by jaxx »

Look at this picture
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MazeratiGTUnten modded.JPG

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madditch
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Post by madditch »

jaxx wrote:Look at this picture
10K goes to the preamp, 27K to the phase inverter.
I built an 18watt version, but didn't like it, too fuzzy. Ended up changing the power section and preamp till I got the tone I was after. I'm sure it probably would sound better at 38 watts with 4 el84s then 2.

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jaxx
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Post by jaxx »

thankyou very much Madd,


phase inverter power resistor couldn't be a less value like 4,7 o 5,7K???


first two colour seem green/yellow and the second one look like blue or violet... :hmmm:


lookin at the posted photos, these two resistors are not perfectly clear to read...




thanx




Jaxx

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madditch
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Post by madditch »

Looks like White, Blue, Red to preamp. Red, Blue, Orange to PI. 9,6K and 26K.

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SPeter
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Post by SPeter »


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schtaf
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Post by schtaf »

Hey again,

Does anyone know a source for 290-0-290 PTs, a la Carmen Ghia? Hammond has 280 and 300, are either of these acceptable?

Thanks

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