[dlparker]

I've been reading through AudioCircle post about in line filters, I'm wondering if using the following filters before a sub and full-range speakers would degrade the signal:

https://www.amazon.com/Harrison-Labs-Satellite-Electronic-Crossover/dp/B00S98PUAK


https://www.amazon.com/FMOD-Crossover-Pair-100-Pass/dp/B0006N41FG/ref=pd_bxgy_1/133-1176176-2773714?pd_rd_w=xmHPW&pf_rd_p=c64372fa-c41c-422e-990d-9e034f73989b&pf_rd_r=G5AF1S620415MRVW0ZJT&pd_rd_r=2009336f-1ca4-4817-8a36-e6aea6ad5aa2&pd_rd_wg=yWwwm&pd_rd_i=B0006N41FG&psc=1

[avahifi]

These are passive circuits and probably won’t damage the sound.  They appear to have several choices available to help a biamped system.

Frank

[dlparker]

Thanks Frank!

[planet10]

It is worth noting that FMODs are poorly implemented PLLXOs.

https://www.t-linespeakers.org/tech/filters/passiveHLxo.html

dave

[trebejo]

Oh, I've been wondering about this for loooong time. I tried a DBX 223 solely as a 1-way to feather the bottom from 20-50 hz and I think it's OK, but when I tried it as a 2-way, the high-pass made a midfi mess of things and I pretty much gave up on the idea of placing a "foreign" object between the preamp and the amp.

But maybe a passive line-level high-pass crossover has a better chance to be ok?! I have a pair of speakers that might improve if they don't have to handle the signal below around 100 hz.

[planet10]

The HP of a PLLXO depends on the input impedance of your amplifier. To make that less of an issue they terminate the filter with something like 5k. This is in parallel with R_in so the preamp suffers if its R_out is not really low.

The HP can be just a single series C, but its value is dependent on the amp’s R_in.

dave

[trebejo]

The HP of a PLLXO depends on the input impedance of your amplifier. To make that less of an issue they terminate the filter with something like 5k. This is in parallel with R_in so the preamp suffers if its R_out is not really low.

The HP can be just a single series C, but its value is dependent on the amp’s R_in.

Subscripts_NICE! I didn't know we had those here.

Thank you, that makes perfect sense. IIRC the AVA hybrid amps have Megohm-ish input impedance, so the single cap sounds like a pretty simple experiment with them. I think the solid state is < 100kohm (maybe 50k?), so that requires a little arithmetic there.

Heh. I just realized that I had put the HP into the solid state and the LP into the hybrid when it all went midfi. I'm sure the DBX as HP still ruins things but I still should have tried it the other way.