PSW10...my misunderstanding

coldmark

I completely missed the boat on what the low pass filter knob does on my PSW10 sub. I'm using it with a 2-channel Yamaha receiver.

I thought it filtered the lows from my bookshelf speakers but I've since learned that everything gets sent to the bookshelves and the low pass knob determines the high end of what gets passed to the subwoofer. My setup sounds good and my bookshelves can handle the lows, but I was thinking I could save some stress on them and improve sound quality by not trying to play all the lows through the 6-inch woofers.

Please correct me if I'm wrong. I'm using this hookup with speaker wire:

2CH RCV ---> SUB ---> SPEAKERS

coldmark

BTW...I have MAIN IN/PRE OUT jacks on this receiver. It's an impressive 90's vintage Yamaha RX-770. But that doesn't do me any good without outputs on the subwoofer, correct? Could I filter the lows from my bookshelves if I added another piece of equipment, like an equilizer?

Sorry for the dumb questions.

sm88

An equalizer isn't the way to go. Set your filter for around 100 hz unless you have some very good bookshelf speakers that can cleanly go lower. The low pass should determine what continues on past your subwoofer to your speakers, unless i'm confused on that. Play around with it and see if you hear differences, such as by turning the volume on the sub all the way down while adjusting the filter and listening to the bookshelf speakers play

coldmark

I got that info from an old thread here. I'll verify it "scientifically" tonight, thanks for the tip!

coldmark

BTW...the Boston CR-8 bookshelves do go pretty low and they have a 7-inch woofer, not a 6.

Here's the frequency response: 48-20000 Hz

I've heard polks that are better, but everyone that hears these little guys is impressed, especially at a price of $50 used and beat up a little.

sm88

The quality matters more than the response really. My BE-718's are magnificent in that they dip down to 50-60hz with very clean, controlled and fast bass. No "muddying" of fast sequences of bass notes and the likes, which is a factor you might not even recognize until you hear it on speakers that can track it. Even so I cross them over at a higher point just as a buffer.

The other reason is because the bass can stack up if you're not cutting off what goes to the speakers. The subwoofer for example might be putting out 25 to 100 hz while your speakers are doing 60 to 20,000. That 60-100 hz bandwidth gets "doubled up" and can sound bloated

John K.

SM, no, that's incorrect. The frequency control on the back of a sub isn't a crossover, although it's frequently referred to as one. It's only a low pass filter on the sub amp, low pass meaning that the low frequencies are let through to be amplified and drive the subwoofer cone, while the higher frequencies are rolled off steeply(not "passed"). This control has no effect on main speakers which are connected through the sub; the connection is straight through, just as if the wire ran directly from the receiver to the mains. A very few subs(not including the PSW10) have a separate high pass filter(typically fixed at about 100Hz)on the speaker level outputs to the mains, but this has nothing to do with the frequency control for the low pass filter.

bamark

John K. wrote: »

SM, no, that's incorrect. The frequency control on the back of a sub isn't a crossover, although it's frequently referred to as one. It's only a low pass filter on the sub amp, low pass meaning that the low frequencies are let through to be amplified and drive the subwoofer cone, while the higher frequencies are rolled off steeply(not "passed"). This control has no effect on main speakers which are connected through the sub; the connection is straight through, just as if the wire ran directly from the receiver to the mains. A very few subs(not including the PSW10) have a separate high pass filter(typically fixed at about 100Hz)on the speaker level outputs to the mains, but this has nothing to do with the frequency control for the low pass filter.

Then how do you separate the low frequencies from the mains?
Or am I missing this?
Reason I ask is that I want to do the same thing.

coldmark

Yes bamark, I thought the same thing, but unfortunately everything gets sent to the fronts.

Mon40CSMM10

One way of separating the low frequencies from the mains is to use "bass blocker" type passive crossovers.

These can be found in most places that install car stereos, Scosche or Metra should still manufacture these. If I recall correctly, these will typically attenuate frequencies below 100 Hz at 8 ohms and 200 Hz at 4 ohms speaker impedance. So although they are primarily intended for car audio use, there is no actual harm when used in home audio.

Use of these passive crossovers using the speaker thru/no separate LFE connect method would be as follows:

1. Full range out from the receiver to the speaker in of the subwoofer;
2. Positive speaker out wire of each speaker connected to the passive crossover, then connect the other end of the passive crossover to the positive terminal/binding post of the speaker;
3. Negative speaker out wire of each speaker connected to the negative terminal/binding post of the speaker as usual.

Serendipity

Oh geez, all this time I thought the crossover on the sub was to send the low frequencies to the sub's woofer, and the highs to the speakers connected to the sub's outputs.

Guess I was wrong.