Mad Professor - Royal Blue Overdrive

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Mad Professor - Royal Blue Overdrive

Postby pamaz » 02 Jan 2014, 09:31

hello all.
Somebody out there has any info that is willing to share?
Thanks

Paolo
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Re: royal blue od - mad professor

Postby miter53 » 08 Jun 2014, 19:22

bump
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Re: royal blue od - mad professor

Postby Dingleberry » 25 Sep 2015, 11:39

Found a gut shot from a Japanese site. Not much but at least something.
You do not have the required permissions to view the files attached to this post.
Simplify before you amplify.

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Re: royal blue od - mad professor

Postby BJF » 27 Jul 2016, 15:44

Hi there,
Right, well what do you want to know?

At your sincere service
BJ

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Re: royal blue od - mad professor

Postby jamesdlow » 30 Sep 2016, 17:36

BJF wrote:Hi there,
Right, well what do you want to know?

At your sincere service
BJ


Not the original poster but I have a few questions.

1) Looks like a bufferless TS style circuit with passive tone right?

2) I know you often use extended feedback loops around the opamps. Any of these at work here?

3) What frequency ranges are your tone and bass pots working at?
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Re: Mad Professor - Royal Blue Overdrive

Postby BJF » 03 Oct 2016, 03:22

Hi There James,
1) if you wish- actually using limiting diodes in the feedback loop is much older than that ;)
2) yes and that one is to limit the HiFi treble-sadly at my age or from rocking too hard in my leathers as it says on the internetz I no longer hear these super sonic frequencies but I know they are there and I can count on them from memory of better hearing days. The way the filter works here is that it feeds back a portion of the highest frequencies and nulls them at the inverting input. The whole point being to have some of the treble present but restricting treble a little.

3) Treble makes boost and cut at about 2KHz but boost is made milder by allowing some upper mids by the aid of the 3-dB filter; Bass makes near symmetrical boost cut at about 100Hz while high pass occours in the circuit at about 70Hz bending the boost downwards at lowest frequencies. The notch created at full boost is centered at about 750Hz and that also makes the peak when in full cut.

At your service
BJ

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Re: Mad Professor - Royal Blue Overdrive

Postby Skreddy » 09 Oct 2016, 02:20

Blah blah blah Where's the perfboard layout, Bjorn!?! :lol:

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Re: Mad Professor - Royal Blue Overdrive

Postby BJF » 10 Oct 2016, 22:22

Hi there,

Actually I was wondering about the correct spelling of blah for the press release of my latest Fuzz:
It sounds like blah and behaves like blah, when you blah it. :hmmm:

Oh I'd be sure someone will do the honours with perfboard :thumbsup

Have fun
BJ
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Re: Mad Professor - Royal Blue Overdrive

Postby HamishR » 27 Jun 2017, 11:51

I have one of these and would be interested in the circuit so I can build an "inspired by the Royal Blue overdrive" pedal. I'm not very good at drawing schematics but I can list all of the components and give and indication where they join if that helps? I tend not to like LEDs as clipping diodes, so they would be the first thing I would change. I think it's actually a very cool pedal. I like having bass and treble controls much better than nature knobs. :-)

Is anyone else interested in how this thing ticks?
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Re: Mad Professor - Royal Blue Overdrive

Postby HamishR » 28 Jun 2017, 12:34

Today I swapped the LEDs out for 1N4148 diodes and I like it a lot better. I'm also sure that a lot of guys would prefer the LEDs! I like the 4148s because they make the sound a bit crisper. They seem to have made the pedal a bit more "rock" to me. Really good overdrive.
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Re: Mad Professor - Royal Blue Overdrive

Postby modman » 30 Jun 2017, 18:38

HamishR wrote:Today I swapped the LEDs out for 1N4148 diodes and I like it a lot better. I'm also sure that a lot of guys would prefer the LEDs! I like the 4148s because they make the sound a bit crisper. They seem to have made the pedal a bit more "rock" to me. Really good overdrive.

Thanks so much for those pictures!
"The whole point of diy is diy. It's not dsoiyathodtr - do some of it yourself and then have others do the rest" (paulc)
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