Parametric Equalizer

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Meat&Beer
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Parametric Equalizer

Post by Meat&Beer »

Hey guys!

I'm gearing up for a new build, (Hoping...) It's just going to be a preamp.

In the works now is a 50w that's slowly going through the debugging process. I have lots of ideas for the next thing, but I really want it to have a 2 or maybe 3 band parametric.

I've done a bunch of searching... and I've found some... stuff. No real leads to a ckt that is seemingly worth breadboarding yet.

From what I have found and read, though, is an indication that this is a serious pita.

Does anyone here have any experience with this type of EQ they'd like to lend advice about?

I have "limited" knowledge in the tube realm, I'm working on it every day. Transistor stuff, I'd rather not get too technical in if at all possible.

Any and all advice/help/criticism is great!
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Leo_Gnardo
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Re: Parametric Equalizer

Post by Leo_Gnardo »

I have run across just one schematic for a tube parametric, in an old circuits book from 1951. Yes, very complicated, just for a single band. And you want 2 or 3 bands. I'd suggest, take an amp with an FX loop and plug in an old Furman or newer Rane solid snake parametric. Try that combination & see if it's really necessary before you commit to such a complex build.
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NickC
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Re: Parametric Equalizer

Post by NickC »

Leo_Gnardo wrote:......... take an amp with an FX loop and plug in an old ........ solid snake parametric ............

Won't that introduce hiss?

:wink:
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Cantplay
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Re: Parametric Equalizer

Post by Cantplay »

I use a Marchand XM 26S in my home stereo.

Q, and crossover points are adjustable by plug in cards, but you could substitute selectors for the board values.

http://marchandelec.com/xm26.html

The schematic is http://marchandelec.com/ftp/xm26man.pdf

John
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Meat&Beer
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Re: Parametric Equalizer

Post by Meat&Beer »

Leo,

I'm sure it's the same one I saw also, not sure which forum it was. They were analyzing it, and came to the conclusion it was unfit for their application, or antiquated, or some reason. But nothing ever solidified with it.

I have a Rane peq, I do not have an absolute need for it to be in an existing amp or mine/I'm not trying to 'fix' something with one... I just love the flexibility of them, my favorite eq by far.

Nothin but time.

Nick,

Thats exactly what went through my head when I read that! Haha! What part of NY are you from? I'm as upstate as you get, Plattsburgh.

Cantplay,

I love it, thank you so much for the info!

I'm moving at the end of the month, so most of my stuff is in boxes. It's so great. :roll:

Just looking to get some stuff in a row so I can try out some fun ckt's when I get re-settled. I'll be sure to post findings (most likely questions) when I get something rolling.

Thanks so much guys, it's very much appreciated!

Very cool forum ya'll have here too. I like it a lot!
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NickC
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Re: Parametric Equalizer

Post by NickC »

Meat&Beer wrote: .......

Nick,

Thats exactly what went through my head when I read that! Haha! What part of NY are you from? I'm as upstate as you get, Plattsburgh.

..................

Greetings!

I've been to Plattsburgh many times. I'm in the Syracuse metro area, but I'm a transplant from Georgia. Ya'll probably get a few degrees colder up there, but we get more snow.

Welcome to TAG! :)
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Leo_Gnardo
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Re: Parametric Equalizer

Post by Leo_Gnardo »

NickC wrote:
Leo_Gnardo wrote:......... take an amp with an FX loop and plug in an old ........ solid snake parametric ............

Won't that introduce hiss?

:wink:
Could do, yes. And if it rattles, run away!

Hm forgot to mention one of my fave para's, Moog.
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JazzGuitarGimp
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Re: Parametric Equalizer

Post by JazzGuitarGimp »

Leo_Gnardo wrote:
NickC wrote:
Leo_Gnardo wrote:......... take an amp with an FX loop and plug in an old ........ solid snake parametric ............

Won't that introduce hiss?

:wink:
Could do, yes. And if it rattles, run away!

Hm forgot to mention one of my fave para's, Moog.
+1 on the Moog: Back in the day, when I was schlepping a stereo, 18-space Anvil flight rack, two Fender Tone Masters, and a pair of MB TL806's, I had two of the Moog 3-band eq's in the rack. I wish I still had them.
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Leo_Gnardo
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Re: Parametric Equalizer

Post by Leo_Gnardo »

JazzGuitarGimp wrote:+1 on the Moog: Back in the day, when I was schlepping a stereo, 18-space Anvil flight rack, two Fender Tone Masters, and a pair of MB TL806's, I had two of the Moog 3-band eq's in the rack. I wish I still had them.
You bet! When mixing I used to insert Moog Parametric + dbx160 compressor on kick drum channel. Powerful stuff. Heavy & takes up a lot of space but nothin' like it. Works a charm on bass too.
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jazbo8
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Re: Parametric Equalizer

Post by jazbo8 »

Meat&Beer wrote:Hey guys!
From what I have found and read, though, is an indication that this is a serious pita.

Does anyone here have any experience with this type of EQ they'd like to lend advice about?
Hi there,

Good to see you here, taking a break from the premap, eh?! :D I helped GoneCat with a PEQ design awhile back, you can read about it here. You need to parallel 3 gyrator sections (the part with the IC) to get your 3-band parametric EQ.

Jaz
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Meat&Beer
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Re: Parametric Equalizer

Post by Meat&Beer »

Jaz!

Hey pal! I didn't recognize you without the flying tube icon. Kind of reminds me of the Rad-Tel logo for some reason.

No, I'll never take a break from the amp you're helping me with over at the other place. It kind of owns me... Ask my girlfriend. :oops:

Great looking info on the parametric, thanks very much! I'm just looking for a little something to do on the side after I get all my stuff unpacked at the new place. Something to poke around at when I'm getting too frustrated with that insanity build I'm at.

I was trying to keep it all analogue, no chips/transistors, but it looks like that is definitely the majority of circuits out there for them. I'll probably end up ordering some of the little black chicklets that will be needed and have em for when I get to it.

As always, thanks!!!
:D
xk49w
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Re: Parametric Equalizer

Post by xk49w »

This might be a tube parametric. I found it here. Listed as a Blonder-Tounge "Audio Baton" (tube graphic equalizer).
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Reeltarded
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Re: Parametric Equalizer

Post by Reeltarded »

omg last thing you guys want is a tube eq.

The Rane 15 and 17 are fine. Move on!
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jazbo8
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Re: Parametric Equalizer

Post by jazbo8 »

+1

As much as we all like tube gear, tube EQ is probably not the best application for it, especially if you want a high Q factor.
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Meat&Beer
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Re: Parametric Equalizer

Post by Meat&Beer »

Holy crap there's a lot of tubes in that thing!!!

So chip is the way to go. It'll be a lot cheaper, that's for sure.

There's also this one that I came across today;

http://www.sabrotone.com/?p=578

A few to choose from now, when some time frees up it'll be review, digestion and order some pahts.
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