Aengus graphic EQ (thumbwheel) information sought--any leads?

GroupDIY Audio Forum

Help Support GroupDIY Audio Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
56SDP30-01PAJS is $13.91 at the 25-piece price, and $12.10 at the 100-piece price.

Not too bad.

Around a ~$100 switch budget per channel doesn't seem like a total deal-breaker to me. Originals are so expensive and hard-to-find that even a several-hundred-dollar build isn't out of the question.
 
Ah, I see.

What would be the consequence of using a BBM switch in this application? Pops on switching?

Yes the amps will produce a small dc offset in mV causing a pop when switching. This can be reduced by using bipolar caps to resistor to ground to shunt the dc. A basic RC HPF typically 47uf & 10k resistor. MBB may cause band interaction for split second while switching. This can be simulated in LT spice with the dc analysis function.
 
Last edited:
I’ll take a stab at this circuit when I get some time. Love 560 on snare kick guitars and bass. I’ll Draw something up in kiCad when I finish another project. Sylvia Massey uses the Anegus on kick and bass I believe. Would be a good compliment of frequencies in series with the 560.
 
Bourns makes s-curve slider pot but they are special order.
What value are you looking at using? The Aengus uses a sum of slightly over 2Meg
A different value would require other changes to the circuit I think.
Take a look at this project. I'm curious how close a 560b would sound simply modifying the CCRR in the gyrators for the frequency points.
 
Getting the q correct is the main thing changing values is not a big issue. I don’t buy into being a circuit purist. That balanced differential input Jensen output would work for me.
 
This was the prototype that we made about 5 years ago (I think).

http://www.audiomaintenance.com/downloads/ez404_prototype.jpg
The top PCB used 741's and had no input transformer.. the lower PCB used some modern IC (not taking it to bits to find out what) and had an input transformer.

Worked fine I believe..... and sounded like the original... they are supposed to be excellent for electric guitar.

Colin.
 
Output amp card schematic. Someone check my work, seems strange (edit, fixed a mistake)
Can't be right. There's nothing driving the output. And the 1K6 doesn't make sense. And there's no way you're going to get 66dB of gain out of a 741. It doesn't have the bandwidth.
 
Can't be right. There's nothing driving the output. And the 1K6 doesn't make sense. And there's no way you're going to get 66dB of gain out of a 741. It doesn't have the bandwidth.
Sorry, that is my mistake, the resistor is actually 3K6 not 1K6.
 
Back
Top