Topic: Question about Church CA-9100 preamp switch

[Carrera2]

Hey there. I know I've seen this on the board somewhere, but I searched and searched and skimmed and skimmed and couldn't find the answer.

My CA-9100 has a small blue switch next to the volume knob. If I remember correctly, when it is not depressed, the "4.7Kohm resistor mod" is not engaged. Or said differently, when the switch is pushed in, the 4.7Kohm resistor is engaged.

Is that correct?

[fmaderjr]

I think so, but you can tell how it works by plugging your mics into the preamp and recorder. Put the recorder in record pause and talk into the mics with the switch both in and out. When the 4.7 mod is engaged the levels will be 10-11 dB lower. It should be simple to tell which setting is on and which is off this way.

[Church-Audio]

I think so, but you can tell how it works by plugging your mics into the preamp and recorder. Put the recorder in record pause and talk into the mics with the switch both in and out. When the 4.7 mod is engaged the levels will be 10-11 dB lower. I should be simple to tell which setting is on and which is off this way.

That is correct. With the 4.7k mod off you get +12 db more gain giving you 32 db gain total for acoustic shows.

[sunjan]

Thanks for the clarification, Chris.
I'm pairing my pre with AT853s (3-wire), it looks identical to the OP, except for my switch being cylindrical black. IIUC it has the same functionality.

And the advantage of engaging the 4.7k mod is less distortion or brickwalling, is that right?

[TimeBandit]

good thread for my question:

i´ve got also an ca9100 Pre now, in the battery case is an switch for HPF filter - ok it´s function is clear for me

and another switch with "PIP On/Off (??)" also hand written there stands "New on V3.4" or something like that- what means that?

[fmaderjr]

Plug in power on/off. Great feature in case someone wants to use the ST-9100 to attenuate the signal from a soundboard, etc. Didn't know Chris was doing that.

[Church-Audio]

Plug in power on/off. Great feature in case someone wants to use the ST-9100 to attenuate the signal from a soundboard, etc. Didn't know Chris was doing that.

There are lots of options for the 9100 That I never talk about.

Chris

[dorrcoq]

Plug in power on/off. Great feature in case someone wants to use the ST-9100 to attenuate the signal from a soundboard, etc. Didn't know Chris was doing that.

There are lots of options for the 9100 That I never talk about.

Chris

Why not?  Don't you want customers and potential customers to know everything your product does? 

[fmaderjr]

Plug in power on/off. Great feature in case someone wants to use the ST-9100 to attenuate the signal from a soundboard, etc. Didn't know Chris was doing that.

There are lots of options for the 9100 That I never talk about.

Chris

Why not?  Don't you want customers and potential customers to know everything your product does? 

I certainly agree with that. And Chris said it was an option (as opposed to a standard feature). Obviously unless we know what the options are, we won't have a chance to order them.

[Church-Audio]

Plug in power on/off. Great feature in case someone wants to use the ST-9100 to attenuate the signal from a soundboard, etc. Didn't know Chris was doing that.

There are lots of options for the 9100 That I never talk about.

Chris

Why not?  Don't you want customers and potential customers to know everything your product does? 

Well nobody ever asked me Honestly there are only a few options for the 9100..

9100 three wire with 4.7k mod
9100 with plug in power switch
9100 stock with 3.5 mm input and output with high pass filter.

[fandelive]

And the advantage of engaging the 4.7k mod is less distortion or brickwalling, is that right?

[fmaderjr]

And the advantage of engaging the 4.7k mod is less distortion or brickwalling, is that right?

Should be no distortion (at least none caused by mics) when turned on. When off your mics are 12 dB more sensitive (12 dB less gain required from preamp) so leave it off when recording stuff that isn't very loud.

[Semayat]

Tks for this thread because I have 2 noob questions :

- How can a -12db (apparently the result of that mod) will result in a non distorted recording?

- In the CA v3.2, there's also a bass R/O function = If I put on that function what is the impact on the recording? I mean compared to a SPSB bass roll off function, for exemple, how can I compare (107hz, 95hz, etc.)??

Tks for any inputs on my questions guys!!

[SmokinJoe]

Tks for this thread because I have 2 noob questions :

- How can a -12db (apparently the result of that mod) will result in a non distorted recording?

- In the CA v3.2, there's also a bass R/O function = If I put on that function what is the impact on the recording? I mean compared to a SPSB bass roll off function, for exemple, how can I compare (107hz, 95hz, etc.)??

Tks for any inputs on my questions guys!!

The 4.7k mod changes the way the mics work, reducing the likelihood of overloading when it gets loud (read up on that elsewhere).  It just happens to result in a 12db difference in output from the preamp, and you can use this difference to tell which mode you are in.  It's not simply a 12db pad which is applied after the fact.

The roll off is to reduce boominess.   Maybe Chris will chime in with frequency and decay is.   If you are using omnis and loud boomy music, you might need it, although a lot of people prefer to leave it off, and roll-off any excess bass in post.  If you are using Cards or Hyper caps, you almost surely don't need it.

[Semayat]

Tks for this thread because I have 2 noob questions :

- How can a -12db (apparently the result of that mod) will result in a non distorted recording?

- In the CA v3.2, there's also a bass R/O function = If I put on that function what is the impact on the recording? I mean compared to a SPSB bass roll off function, for exemple, how can I compare (107hz, 95hz, etc.)??

Tks for any inputs on my questions guys!!

The 4.7k mod changes the way the mics work, reducing the likelihood of overloading when it gets loud (read up on that elsewhere).  It just happens to result in a 12db difference in output from the preamp, and you can use this difference to tell which mode you are in.  It's not simply a 12db pad which is applied after the fact.

The roll off is to reduce boominess.   Maybe Chris will chime in with frequency and decay is.   If you are using omnis and loud boomy music, you might need it, although a lot of people prefer to leave it off, and roll-off any excess bass in post.  If you are using Cards or Hyper caps, you almost surely don't need it.

Alrigh, 1st, tks.
I did actually talked about that via PM with Nick and he helped me understand that the same way.

The 1st recording I did using the AT853>CA9100 last wednesday was fantastic...I can't wait to use it one more time!!