Silent Circuit questions

[roburado]

1. Is there a place where I can read more about the Silent Circuit beyond getting a statement saying that it retains single coil sound but keeps things quiet.

2. Is it "active" in the sense that EMGs are "active?"

 

[Spudmurphy]

It uses a battery so I guess that means it's active although of course my Seymour Duncans SSS are not active pickups on my AL.

 

[candid_x]

I'm not knowledgeable regarding electronics, but I believe the Silent Circuit acts to reverse ground the neck pickup (on SSH), which effectively eliminates the 60 cycle single coil hum, but the guitar functions without the 9v battery so I wouldn't call the SC 'active', per se. The SC is engaged whenever the guitar cord is plugged into the guitar, though I’m told the current draw is minimal.

I also have a question about Silent Circuit: It seems that without the battery installed there's a slightly hotter and defined signal. Is this just my imagination, or is the Silent Circuit function truly transparent?

Bruce

 

[beej]

1. Is there a place where I can read more about the Silent Circuit beyond getting a statement saying that it retains single coil sound but keeps things quiet.

You can check EBMM's patent.

I've never taken one apart, however the approach of using a "dummy" coil for noise cancellation has been done a few different ways. EBMM's approach works really well, as do some noiseless pickups that have dummy coils built into them (Bill Lawrence, etc.)

2. Is it "active" in the sense that EMGs are "active?"

No, not in the same sense- the impedance is still the same as other passive pickups. In otherwords, though it's powered, it doesn't act as a preamp.

 

[hepkat]

I've often wondered about the signal being "hotter" with the battery out on my MM90... To my ears (and they are old & tired) they sound more like the "traditional" P-90 sound I'm used to without the silent circuit. Just an observation. I'm sure alot of it has to do with they type of wood in the guitar, etc. When playing clean country style I love the silent circuit... Noise Free...

 

[candid_x]

Hep, yup, that describes it well. But then my ears are also old, and I have fooled myself before with differences I have heard in small gear adjustments. But I do think you sum it well regarding the “clean up” working to an advantage aside from just eliminating or reducing hum, especially when playing clean. For crunch and gain, I “think” I detect some signal hotness lost. At present, both of mine are sans batteries. But if I went into the studio tomorrow to lay down a clean track, I’d drop one in. It’s a nice option to have at any rate.

 

[hepkat]

If I keep my axis MM90 I wonder if I could consider a switch to activate/deactivate the silent circuit? A push/pull pot maybe. Haven't had the battery in for several months while playing gigs.

For blues I would play without a battery. Country or clean pop, or in studio I always pop in a 9 volt.

 

[roburado]

Thanks guys!