Have an integrated amp with only 1 subwoofer out...

If you are using one source component only ie a cd player you can install the equalizer between the source and the integrated.  Ideally, the integrated would have a tape loop in/out and the equalizer would be installed in the tape loop.  Then equalization would be available on all sources when the tape loop is engaged.

Thank you for the response.  

There is no tape loop in/out.  Just the inputs for the cd, aux, phono, etc.

Question.  If the equalizer has inputs for each component, can I plug the components into the equalizer first, and from the equalizer output, just run one set of RCA cables to one of the inputs on the amp?

First graphic is back of equalizer and second is back of amp.

Sorry.  Graphic did not come up, but I think you get the drift.

Equalizer inputs - dvd, audio, tuner, aux

Equalizer outputs - Rec Out - 2 left and 2 right

Amp inputs - Coax, Aux, Phono

Amp outputs - SW out

Bad idea an analog graphic eq will degrade clarity  digital eq is available through roon 

Why are you adding an equalizer?  That’s just a bandaid for something that is off in your system.  Better to identify the source of the issue and address that rather than inserting another piece of equipment into the signal path.  Look at any reviewer’s system or go to any high-end audio store or audio show and you won’t find an equalizer anywhere, and there’s a very good reason for that.  Do it the right way, not with bandaids.  Just my $0.02 FWIW. 

My humble opinion is quite different.  I have a 6-band equalizer between my CD/SACD player and my integrated amp and use when I play certain discs and its wonderful!

For example, nearly all (all?) early Motown recordings have very little low end and a bit too much high end.  A judicious use of the equalizer makes Tham sound amazing!

So in my opinion/experience, the issue is the recording.  I know of no other way to address this. Do you, @soix ??

With a tape/processor loop.

it seems you might want to get an amp with better connectivity options.

Or perhaps a cheaper alternative would be to get a preamp with a tape loop and insert that between your sources and your amp.

So in my opinion/experience, the issue is the recording.  I know of no other way to address this. Do you,

@rpeluso  Yeah, this is definitely a case of different strokes for different folks and I don’t think either of us is wrong — we just handle it the way that works best for us.  For me, I don’t want to insert any extra cables and equipment into my system if not absolutely necessary.  I only listen to well-recorded music on my main system and I don’t want anything to potentially degrade the sound of those recordings on my system, and I find it hard to believe inserting an equalizer and another pair of interconnects onto the signal path doesn’t have at least some negative effect.  If I listen to less well-recorded material I’ll listen to it on a Bluetooth speaker or something similar, but there’s so much excellent well-recorded and new music via Qobuz out there I really never feel the need to listen to poorly recorded music.  One example — I’m a huge Steely Dan fan but especially their earlier stuff is not well recorded (at least digitally) so if I get the urge I’ll enjoy them on my Bluetooth speaker (Audio Engine B2) and enjoy it just fine.  Anyway, that’s what works for me and glad you’ve found a great solution that works well for you, and the world keeps spinning. 

Run one set of the L&R outputs from equalizer to the aux L&R  inputs on integrated. Run sources to equalizer. 

Why not take an RCA splitter cable with one connection to the IA and two out. One to sub; the other to the EQ?

Not sure if this will diminish the out signal, but I once used this to power two subs from a single IA out port and it seemed to work just fine.

I tried to splitter, with mixed results. Does your sub have a speaker connection/binders?  

How would that work with the splitter?  I have only one sub out on the integrated amplifier. What would the routing wiring be?

And the sub has the following on the back:  

Left and Right Line In / Sub in

2 speaker level in's.  (2 left and 2 right)

use the speaker level inputs from your amp's speaker out, it worked for me nicely. The split is a Y giving you two  outs from your pre-out on your amp. If you don't have a pre-out, how would you connect the EQ?