J Rockett - The Dude (gut Shots)

rafikian · Post by **rafikian** » 04 Nov 2016, 14:43

My friend has juste lent me his Fantabulous J Rockett The Dude, this peadl is AWESOME !!
Did take some pictures

this is a double sided PCB with 3 x 4558 smd IC
Pots are
Lvl = B50K
Ratio= A250K
Treble=B10K
Deep=C25K
I ll put the values of the Rs and Cs when possible.
Cheers
Rafik.

MGaburriJazzDude · Post by **MGaburriJazzDude** » 23 Dec 2016, 15:16

It's just me, or there are too many OP Amps in there?

induction · Post by **induction** » 23 Dec 2016, 15:55

Too many for what?

alexradium · Post by **alexradium** » 23 Dec 2016, 16:01

induction wrote:Too many for what?

for a chicken brain...

MoonWatcher · Post by **MoonWatcher** » 23 Dec 2016, 20:27

MGaburriJazzDude wrote:It's just me, or there are too many OP Amps in there?

If it's mostly copied from an existing design, then 3 op amps would be 'just right.'

MGaburriJazzDude · Post by **MGaburriJazzDude** » 23 Dec 2016, 23:39

I mean, aren't 6 op amps a lot for a traditional overdrive?
Are we in front of a totally new overdrive topology?

But, thinking about it a bit, it could be that they've used multiple gain stagesin series or something like that. I don't know, i will be amazed if someone told that finaly a boutique manufacture came up with a completely new overdrive design... It would be amazing, wouldn't it?

(Excuse my rough english...)

alexradium · Post by **alexradium** » 24 Dec 2016, 12:39

MGaburriJazzDude wrote:I mean, aren't 6 op amps a lot for a traditional overdrive?
Are we in front of a totally new overdrive topology?

But, thinking about it a bit, it could be that they've used multiple gain stagesin series or something like that. I don't know, i will be amazed if someone told that finaly a boutique manufacture came up with a completely new overdrive design... It would be amazing, wouldn't it?

(Excuse my rough english...)

opamp or transistors are used for many different tasks,buffering,clipping,mixing,recovery,high,low or bandpass filters,differential,servo dc....
it could be one for input and output buffers,one for clipping,one for tone,one for a gyrator,who knows...anyway there are several pedals that use a lot of opamps,Blakstar and Tech21 most notably.

MGaburriJazzDude · Post by **MGaburriJazzDude** » 24 Dec 2016, 14:21

alexradium wrote:
MGaburriJazzDude wrote:I mean, aren't 6 op amps a lot for a traditional overdrive?
Are we in front of a totally new overdrive topology?

But, thinking about it a bit, it could be that they've used multiple gain stagesin series or something like that. I don't know, i will be amazed if someone told that finaly a boutique manufacture came up with a completely new overdrive design... It would be amazing, wouldn't it?

(Excuse my rough english...)
opamp or transistors are used for many different tasks,buffering,clipping,mixing,recovery,high,low or bandpass filters,differential,servo dc....
it could be one for input and output buffers,one for clipping,one for tone,one for a gyrator,who knows...anyway there are several pedals that use a lot of opamps,Blakstar and Tech21 most notably.

You're right, i didn't think about it that way...

By the way, is there any clue of whats going on in that lil' black box?

Post by **Saruman** » 27 Dec 2016, 07:44

schematic?

1oldsidewinder · Post by **1oldsidewinder** » 31 Dec 2016, 20:50

Not all the op-amp stages may be in use. IIRC, the Blue Note only used half of a 4558. Another possibility might be a charge pump. Also the Dude's "ratio" control is supposed to be a clean blend. I guess a dual gang pot might be a clue. Just a guess but Rockett has had a lot of success with their Klones.

matt239 · Post by **matt239** » 20 Jan 2018, 06:15

Any idea how the thing works?

Oloorin · Post by **Oloorin** » 25 Mar 2020, 09:45

J.Rockett The Dude schematic from PedalPCB.

Interesting design, has a lot of tone shaping.
So "Ratio" knob is just a regular "Drive"/"Gain", not an actual clean blend as the manufacturer says.
It has a combination of soft and hard clipping.
Active tone shaping with 2N3904 gyrator circuit.
Another soft clipping stage with low frequency control "Deep" is after the volume knob, which is quite strange? So with more volume there is more overdrive.
passive tone "Treble" control on the output.

cbriere · Post by **cbriere** » 25 Mar 2020, 12:44

the output is just like the 45 special.

culturejam · Post by **culturejam** » 25 Mar 2020, 14:37

Oloorin wrote:Interesting design, has a lot of tone shaping.

Sort of reminds me of several of the DOD drive circuits with the gyrator and other filtering going on.

Dr.Detroit · Post by **Dr.Detroit** » 25 Mar 2020, 19:48

From the beginning part up to the volume control is very close to the Nobels ODR-1 with a fixed "Spectrum" control.

Oloorin · Post by **Oloorin** » 25 Mar 2020, 21:35

So, it's just Nobels ODR-1 with and Rockett 45 stacked