Splitting Preamp Output--Affect Sound Quality?

If I used a Y-splitter to divide the output from a preamp between a sub and a power amp, would this compromise sound quality?

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I've been using Phoenix Gold RCA Y-splitters at the back of my Blue Circle BC21 feeding a 2 channel power amp and subwoofer amp and have been quite happy doing so.

Last year I compared the BC21 against other preamps that have two sets of outputs and still preferred the BC21. I realize this doesn't technically address your concern about splitters, but more so differences between preamps.

The BC21 was my favorite. But you're right, I really should see how it sounds without the adapter. I have no way of attaching a subwoofer without it though.

What components are you using or contemplating configuring in this fashion?

If you use a good quality splitter there should be no difference between sound from a pre-amp that has an extra set of pre-outs wired in for convenience.

The issue, in my opinion, has less to do with the Y-connector itself (as long as it's decent) than it does with the impedances of the amp and sub. With the Y-connector, their input impedances are paralleled and, if equal, the preamp sees half the load as with the amp alone. If the preamp can handle this (and most can), fine.

Another issue is the relative impedances of the two paralleled loads. If one is significantly less than the other, it will shunt signal current from the other. Again, this may or may not be a problem depending on the values and the preamp.

I, for one, use a preamp with multiple individually-driven outputs so such issues do not apply.
Thanks for the responses. I currently have an NAD C370 integrated amp with two preamp outputs. I was just wondering how I would handle my sub if I decided to upgrade to something like the Creek 5350SE.

I would check your IC (interconnect cable) very carefully, and specifically measure the IC capacitance, if possible. I recently checked a customer's homemade IC, 20 footer, and found the capacitance to be 15,500 pf; astronomically high.

Another consideration is the input impedance of the components. If the input Z of one, or both is low, and the preamp has capacitive output coupling, it may reduce the bass response.


SAS Audio Labs