Dr.Z For All

Tube or solid-state, this section goes to eleven!
User avatar
Barata
Information
Posts: 22
Joined: 24 Aug 2007, 16:20
Been thanked: 2 times

Post by Barata »

Hi,
I'm planning to build a MIni-Z amp what you would suggest for the PT and OT?
Thank you!

User avatar
klingo
Information
Posts: 11
Joined: 21 Mar 2008, 08:10

Post by klingo »

fluzo wrote:I have tried the Route 66 BASS + TREBLE eq in my EF86 amp and it doesn't suck tone.

Any ideas on how to make the treble control more "trebley"? The bass pot works fine but the treble pot is a bit dark to my ears...

Thanks for your help.
in mine the treble pot add highmid/treble (and distortion in these frequencies at the end) .not too dark for me, but you may prefer a smaller treble cap
you may try 470pf instead of 1000pf or use an "edgier" type of cap ( ceramic, polyprop ...) instead of mica.

User avatar
fluzo
Information
Posts: 18
Joined: 21 Sep 2007, 08:10

Post by fluzo »

Thank you klingo I'll try that.

I've experimented with the route 66 bass + treble config in my amp, which mounts an AC15 EF86 preamp in a Marshall 18W power amp, both stock circuits as in the schematics. I sounds good with lots of "balls" but has almost no headroom. The route 66 eq adds a lot of gain, specially the treble pot. Is there a way to reduce the gain of the circuit while keeping its character?

I've also tried the carmen ghia/stang ray tone control on the other channel, works backwards as expected and the range is fine but lacks the character of the route66 config.

In a AC15 power amp it sounds horrible, too fuzzy and not warm at all.

I think it would work better with a KT66 power amp as it has more headroom...

User avatar
skibum1999
Information
Posts: 10
Joined: 04 Jul 2008, 00:14
Been thanked: 1 time

Post by skibum1999 »

Barata wrote:Hi,
I'm planning to build a MIni-Z amp what you would suggest for the PT and OT?
Thank you!
I seem to remember reading that Dr.Z uses this MOJO OT http://www.mojomusicalsupply.com/item.a ... id=MOJO771

As for the PT, try this

http://www.mojomusicalsupply.com/item.a ... id=MOJO771

just suggestions

User avatar
Cow4prez
Resistor Ronker
Information
Posts: 269
Joined: 11 Jul 2008, 18:01
Been thanked: 6 times

Post by Cow4prez »

anyone built their carmen ghia yet? Which replacement transformers do you use?

User avatar
KHELSTROM
Solder Soldier
Information
Posts: 205
Joined: 06 Sep 2007, 15:30
Has thanked: 2 times
Been thanked: 6 times

Post by KHELSTROM »

Cow4prez wrote:anyone built their carmen ghia yet? Which replacement transformers do you use?
I built mine a while back by using a Hammond AO-35 amp just like the Dr. used to build originals. I had great results and after playing a real one I must say it's dead on.

User avatar
doug deeper
Breadboard Brother
Information
Posts: 95
Joined: 06 Dec 2007, 17:39
Been thanked: 101 times

Post by doug deeper »

anyone have any advice an transformers for the stangray?
maybe something in a weber????!?!?!?! :thumbsup

User avatar
Voozle
Information
Posts: 8
Joined: 15 Jun 2008, 17:23

Post by Voozle »

If you look at it, the Stangray is more or less a one-channel Ac30, so I guess you could use the ones that go with an AC30. If I'm wrong here, please correct me, but it makes sense to me at least :scratch:
Cheers
Voozle

User avatar
invalidcd
Breadboard Brother
Information
Posts: 72
Joined: 26 Jul 2007, 17:56
Location: Austin,TX
Been thanked: 14 times
Contact:

Post by invalidcd »

doug deeper wrote:anyone have any advice an transformers for the stangray?
maybe something in a weber????!?!?!?! :thumbsup
OT:4K@40W

PT:290-290 @350ma

since the OT was designed by ken fisher your best bet is to use the toneslut transformers , those guys are awesome and they wont charge you an arm and a leg (less than $200 for both)

But i have built this amp, the one thing i did that i should have put in the schematic was add a 6 position rotary for the coupling(freq)cap. this made a world of difference.

Im not that impressed by this amp as much as i am the carman ghia its one of my favorite amps that i've built ,it very clean and compressed its different.
And the Stang Ray is totally Tom Petty , which i love.

User avatar
madditch
Information
Posts: 9
Joined: 04 Apr 2008, 21:08

Post by madditch »

I'm building a Mazerati GT and wanted to know what the value of the resistor attached to V1 pin 7 is. It's not labeled in the schematic. Thanks.

User avatar
marshmellow
Cap Cooler
Information
Posts: 469
Joined: 16 Aug 2007, 07:31
Location: Germany
Has thanked: 20 times
Been thanked: 127 times

Post by marshmellow »

2,1k resistor

User avatar
telecaster
Resistor Ronker
Information
Posts: 444
Joined: 17 Jan 2009, 00:57
Has thanked: 162 times
Been thanked: 12 times

Post by telecaster »

Anyone have a layout for the mazerati?
KindaFuzzy - Looks like a blue nail polish and nutella sandwich.
Freekish - "Our originality is in the basement. Our business is in the toilet"
Guitarlcarl - I did take offence at being called an idiot by a moron.

User avatar
DougH
Transistor Tuner
Information
Posts: 1087
Joined: 18 Aug 2007, 04:53
Has thanked: 4 times
Been thanked: 23 times

Post by DougH »

There is an old ampeg tone stack circuit that is very similar to the Rt66 tone stack. I can't remember the model #. The mullard amp looks interesting. Just shows that all of this stuff comes from somewhere.

edit: re. mullard amp- Wow, ultralinear too. Amazing... I wonder how much personal credit these boutiquers take for coming up with this stuff?...
"You have just tubescreamered or fuzzfaced yourself " -polarbearfx

User avatar
Ben N
Cap Cooler
Information
Posts: 506
Joined: 12 Dec 2008, 03:34
my favorite amplifier: Ampeg J12D Jet
Location: Israel
Has thanked: 192 times
Been thanked: 53 times

Post by Ben N »

OK, let's be fair: Obviously Mike Z didn't invent EF86 input stages or UL outputs--it's all been around for a while (ever hear of Dynaco?). But using those things in a clean audio amp hardly makes their use in a guitar amp designed to compress and distort obvious. Some of us are old enough to remember Fender's effort at UL guitar amps in the 1970s, which were almost universally panned (except by pedal steelers) as sterile sounding. Dave West's amps (derived from Sunn, which were derived from Dynaco) were UL and were tonally better than the Fenders, but I recall hearing they had noise issues. Vox and Matchless used EF86s, but not with real tone stacks. Dr. Z didn't invent these things, but he applied them in an innovative way to make them into a really good sounding amp. This is not trivial.
Or, to put it another way, if it was all so obvious, how come no one (present company included) ever did it before?

User avatar
DougH
Transistor Tuner
Information
Posts: 1087
Joined: 18 Aug 2007, 04:53
Has thanked: 4 times
Been thanked: 23 times

Post by DougH »

Is that actually a "clean" hi-fi amp? With an EF86 driving (with no lossy tone stack) a long-tailed-pair and a pair of KT66's??? Yikes...

I don't really care where Dr. Z gets his ideas from or if he lifted it wholesale from that Mullard schem (which it appears he did, to me anyway, the topology is too close to be sheer coincidence). But just don't give me this stuff about how 'he uses a clean sheet of paper and his amps are not modifications of anything else' (paraphrased), which has been said about his stuff (maybe on his website? Don't remember).

Most if not all, guitar amps are based on circuits that are already and have been out there, probably for generations. There are a few new ideas popping up here and there but they are far and few between. Peace. That's the way the guitar amp biz works and I have no issue with that.

But if someone claims he is an innovator, or lets someone else claim for him that he's an innovator- then he better damn well be one. Otherwise, he's just a charlatan AFAIC. In some ways I think the boutique 3-ring circus makes a mockery of the great ideas that feed it.
"You have just tubescreamered or fuzzfaced yourself " -polarbearfx

User avatar
SpencerPedals
Solder Soldier
Information
Posts: 229
Joined: 23 Jan 2009, 21:56
Been thanked: 10 times

Post by SpencerPedals »

I'd also be interested in a layout for the Mazerati. The pic is really damn good for it, but I'm a super newbie when it comes to amps.

User avatar
Ben N
Cap Cooler
Information
Posts: 506
Joined: 12 Dec 2008, 03:34
my favorite amplifier: Ampeg J12D Jet
Location: Israel
Has thanked: 192 times
Been thanked: 53 times

Post by Ben N »

DougH wrote:Is that actually a "clean" hi-fi amp? With an EF86 driving (with no lossy tone stack) a long-tailed-pair and a pair of KT66's??? Yikes...
Well, intended to be, anyway. :)
DougH wrote: I don't really care where Dr. Z gets his ideas from or if he lifted it wholesale from that Mullard schem (which it appears he did, to me anyway, the topology is too close to be sheer coincidence). But just don't give me this stuff about how 'he uses a clean sheet of paper and his amps are not modifications of anything else' (paraphrased), which has been said about his stuff (maybe on his website? Don't remember).

Most if not all, guitar amps are based on circuits that are already and have been out there, probably for generations. There are a few new ideas popping up here and there but they are far and few between. Peace. That's the way the guitar amp biz works and I have no issue with that.

But if someone claims he is an innovator, or lets someone else claim for him that he's an innovator- then he better damn well be one. Otherwise, he's just a charlatan AFAIC. In some ways I think the boutique 3-ring circus makes a mockery of the great ideas that feed it.
I'm not familiar with whatever marketing/fan hocum has been spread about here--I tend to ignore that stuff, so it doesn't really make an impression. My point is that one doesn't have to "uses a clean sheet of paper" or make stuff that is "not a modification of anything else" in order to be an innovator. Otherwise, what was so special about a '59 Bassman, really, that wasn't covered in Western Electric theater amps 30 years earlier? Still, there aren't many of us who would accuse Leo of having been a "charlatan" for using familiar bits to create something undeniably special. Regardless of the puffery, to my mind the Rt.66 is indeed an innovation (if only an incremental one, as you correctly point out), and not less so because the circuitry is familiar from other contexts.

User avatar
DougH
Transistor Tuner
Information
Posts: 1087
Joined: 18 Aug 2007, 04:53
Has thanked: 4 times
Been thanked: 23 times

Post by DougH »

Ben N wrote:
I'm not familiar with whatever marketing/fan hocum has been spread about here--I tend to ignore that stuff, so it doesn't really make an impression. My point is that one doesn't have to "uses a clean sheet of paper" or make stuff that is "not a modification of anything else" in order to be an innovator. Otherwise, what was so special about a '59 Bassman, really, that wasn't covered in Western Electric theater amps 30 years earlier? Still, there aren't many of us who would accuse Leo of having been a "charlatan" for using familiar bits to create something undeniably special. Regardless of the puffery, to my mind the Rt.66 is indeed an innovation (if only an incremental one, as you correctly point out), and not less so because the circuitry is familiar from other contexts.
IMO there's a big difference between using "familiar bits" (or even converting a bassman to a jtm45) and taking an existing schematic, re-implementing >95% of it and kinda sorta letting everyone believe it's something you did all by yourself. And that BTW, is reinforced both by web site marketing fluff and the fact that this builder has a well established rep for angrily rebuking anyone who dares to reverse or share what's inside "his" work. What is he trying to protect anyway? The 1-5% of the changes he made?

Again, it has the appearance of yet another boutiquer who doesn't want to be "found out". And this same old scene plays out once more. I apologize if it seems like I've overreacted to this. It's really not a big deal. It's just a disappointment, that's all.
"You have just tubescreamered or fuzzfaced yourself " -polarbearfx

User avatar
Ben N
Cap Cooler
Information
Posts: 506
Joined: 12 Dec 2008, 03:34
my favorite amplifier: Ampeg J12D Jet
Location: Israel
Has thanked: 192 times
Been thanked: 53 times

Post by Ben N »

OK, I understand your feeling about the hype and the attitude. Doesn't change the merits of the amp, though. Still, just taking an EF86 input (without a tone stack), an LTPI and a UL push-pull output (different biasing, by the way) does not give you a successful guitar amp. Even recognizing that as a potentially successful formula is pretty creative in my book. It's that last 5%, picking up on the form, tweaking it til the form meets the intended function, that gets you there.

User avatar
Ben N
Cap Cooler
Information
Posts: 506
Joined: 12 Dec 2008, 03:34
my favorite amplifier: Ampeg J12D Jet
Location: Israel
Has thanked: 192 times
Been thanked: 53 times

Post by Ben N »

Sorry, too late to edit, I guess. Doug, what happened since your more deferential tone to Mike Z at the time you released, ever so gingerly, the Highway 89? Just curious. Honestly, I have no personal stake in this. But isn't boutiquers' claiming just a bit too much originality for recycled topologies just the mirror image of DIY-wannabe-critics dismissing any dual-opamp-with-clippers as just another TS-clone?

Post Reply