Subwoofer to a stereo setup help.

- L+R speaker-level outputs on the receiver to L+R speaker-level inputs on the subwoofer.
- L+R speaker-level outputs on the subwoofer to the left and right speakers.
- Adjust the crossover* on the subwoofer.

(*There doesn't appear to be any information on the FR of the Alto 620s - not even on the Sherwood website - but, given that they have a 6" driver, I'd start at ~80-100Hz and go from there.)

I didn't mean to state the obvious, but the diagram you posted shows the receiver running one connection to a speaker and one connection to the sub for each channel. This is different from what I wrote. I don't know what would happen with that type of connection you indicated, but with a receiver-to-sub-to-speakers connection, there should be minimal/negligible signal or power loss.


35Hz is very optimistic.

Oh. Hmmm. Well, in that case, please disregard my comments.



-- Edit --
I noticed that the manual also suggests the following connection method per channel: Receiver-to-speaker-to-subwoofer. Perhaps that's worth a try...?

All the connection methods presented here represent the same exact parallel connection to the sub and speakers. And they'd all be fine. Of course, the sub doesn't have speaker level outputs so that one's out.

The only difference that might theoretically exist between those methods is that sometimes a sub's speaker level outputs are high-pass filtered, in which case how you connected things would make a difference. But, again, the sub has no speaker level outputs so it's irrelevant, here.

Fernand-7, there is no power drainage from the speakers. The sub has its own amplifier and presents no load or power drain to the receiver, at all, with any of the connection schemes discussed in this thread.

Just as an aside and FYI, even when a subwoofer's speaker-level outputs are high-pass filtered, the sub's low-pass filter (it's not really a "crossover") setting does not affect what is sent to the speakers. The high-pass filter, on so equipped subs, is fixed at a particular frequency. Very few, if any, subs feature a true continuously variable "crossover".

So, if the sub's speaker-level outputs are high-passed, it is a fixed high-pass filter value (usually somewhere in the neighborhood of 80-120Hz) with a variable low-pass filter (sometimes incorrectly called its "crossover") setting that you adjust to taste and/or to the high-pass filter frequency that is being applied to the sub's speaker-level outputs. If the speakers roll-off above that fixed high-pass frequency, then you can usually, depending upon how high the sub's variable low-pass filter can be set, adjust the sub's variable low-pass to a higher setting that is more appropriate to the speaker's roll-off.

There ARE many subs whose speaker level outputs are not high passed at all, though, and in this case those speaker-level outputs simply represent pass-through connections that pass a full-range signal on to the connected speakers.

a quick google search turned up four 'line level to RCA converters' for less than $20. The most expensive of those was only eleven bucks on amazon, plus seven for shipping. If you have Prime it may be less...
seems like it might work, cheaply...
Joe

Unnecessary and will provide no advantage in this instance. Could even be detrimental. A speaker-level connection will work just fine, here.

No. Because it has its own amplifier, the impedance that the sub presents is so high that it is irrelevant. It, essentially, presents no load. The receiver's amps will still operate at the same impedance were the sub not connected. So, don't sweat it.

BTW,with 6ohm speakers, the sub would have to present an impedance of 6ohms, too, for the parallel impedance to be half the value of the two impedances. Anything else and the calculation becomes more complicated than simply halving the two identical impedances.

Thanks for the info. That is very interesting to know.

And I feel kinda foolish for having always assumed that a "crossover" on a subwoofer actually did what its name - in my mind - implied it did.