Adjusting P3 - a video

Looking at focusrite scarlet solo for interface. I understand I have to attenuate output of amp to input of interface.
I've got a couple of software suggestions here. I suspect I'll be on a learning curve and likely be looking guidance getting off the ground. Before I pull the trigger , any last thoughts , suggestions for interface or software. For the record , I'm looking for simplest , easiest to use medium without short changing the operation. I don't feel I need the most comprehensive version.
 
You can also use the XLR input of the Focusrite.

I built this board that I use with the Focusrite solo. The input can be from a power amp (speaker binding post) or a preamp (RCA, one channel only).

For speakers, output of the power amp goes to the 8 ohm load from the binding post, then voltage divider of 22K and 2.2 k, then the output is taken on the 2.2k to make it lower, then RCA out, then to the attenuator (not shown but RCA to RCA) then to the Scarlet Solo input (RCA to XLR or RCA to 1/4).
For preamp, the same connection except input to the board is RCA then to 10k load resistor.

Cables that you need: XLR to RCA for loopback only. XLR to 1/4, RCA to RCA, and 1/4 to RCA (output of the Solo to preamp/amp IN) for testing.
 

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Yes, I'm participating in that, and did long ago when I made my thread "adjustment of P3 for the average hobbyist" from back then. My 2i2 is out of the box, I need to build all the connectors and these seem to be capable, just with correction wasnt sure if the Loop cable as described in previous post is still needed. I am assuming not.

Delay was needing to up grade old laptop that was getting crash prone. That is done and I'm ready to drive myself crazy twiddling P3.

Russellc
 
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Check out this post for a very clever project for attenuation.

The BA-3 as preamp build guide

yes, I need that attenuation! I learn the "hard" (=expen$ive) way often enough! Thanks for the reminder, include those parts in next order.

Dammit, I just opened up my box of new small beta AlephJ boards and parts collected so far to add any of those parts to order, and somehow I have some J2 clone boards about the same size in there!

Another delay, where in the wide world of sports are those boards? I guess it would be prudent to check the "J2 clone ans SEmiSouth box, they are probably in there.

Russellc
 
So no XLR to RCA needed? or in addition? I'm making these as well, if I can't find ready made at Amazon or some such.


Russellc

Hi,
My Focusrite Solo has female XLR and female 1/4 inputs, and L & R 1/4 outputs. I use the Male XLR to Male 1/4 cable as the loopback cable (output of the Solo to the input of the Solo).
When I test preamps or amps, I use RCA to XLR in my set up because I chose to have RCA output for the attenuator that I use. Hope I explained it clearly.