Boss FA-1...TC dual parametric eq

Started by Music, January 02, 2007, 01:01:18 AM

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Music

Hi, anyone got the schematic of the Boss FA-1 fet amplifier and TC eletronics dual parametric eq?, im lookin some of The Edge's classic tone stuff..
Thanks and happy new year.

MartyMart

"Success is the ability to go from one failure to another with no loss of enthusiasm"
My Website www.martinlister.com

alfafalfa

A short time ago I found the TC Electronics Par eq manual:

Here you can see it:   http://www.esnips.com/web/avanluijt-Pictures

Alf

Music

#3
Thanks, anybody has built any of those circuits?
I've note that the layout for FA-1 it's incomplete, i found this schem http://www.schematicheaven.com/effects/boss_fa1_fet_amp.pdf, it seems to be complete, anybody?.
Bye.

Mark Hammer

You can also look here for some similar types of pre-amp/EQ circuits, for comparison purposes: http://experimentalistsanonymous.com/diy/

Look under the OOP Japanese Electronics Book directory.

ustompsteve

In what way is the layout incomplete?

--Steve

Mark Hammer

I think perhaps he means that, in relation to the more typical Boss pedal with all the switching circuitry, it just seems like kind of a conspicuously spartan schematic/circuit.  Of course, carve away all the switching and buffer stuff from a great many Boss and DOD pedals, and they can get pretty darn simple too.  I suppose if E-H had ever used FET switching for their early pedals, or if MXR had used it for the Dist+, we'd be looking at schematics of the "pared down" circuits and feeling a little uncomfortable with the seeming "incompleteness" of those circuits too. :icon_wink:

ustompsteve

The FA-1 was in the circuit all the time. It didn't have any switching except for the filter circuit.

I uploaded the schematic from the original Boss Service Manual. That is what I did my layout from.

I swapped a modern dual op-amp in place of the original in-line units. I don't think that should affect the tone at all.

In fact, in my opinion, this thing doesn't really have a tone of it's own. It is a very clean boost w/ tons of gain.

--steve

Mark Hammer

*I* knew that, and *you* knew that.  Not everyone does, though.  Indeed, there have been many things over the years that were always in-circuit and never switched out.  My old MXR 6-band had no bypassing of any kind whatsoever.

okgb

Can't see the dual eq schematic there ,
I had the whole manual which they had sent long ago ,
turned out the sanded off i,c, was a common quad
now all i can find here is the pcb layout !
anyone ?    gboboski at shaw dot ca