Questions about the benefit of using an active crossover in my setup

[bcycle]

Hi,

I’m wondering the practicality and potential benefit of adding an active crossover into my system. My goal would be to have the main speakers and sub sound great not just for HT but also when listening to my music with no processing (Yamaha calls it pure direct). (Currently the sub is connected to the Sub Out which I understand is only used when in surround modes on my Yamaha RX-2500)

Properly done, I’m hoping an active crossover will allow me to change the “bass out” setting for surround modes to the front speakers so I that the sub is in use not only in the surround modes, but also when listening to 2 channel stereo or in Pure Direct” where the receiver bypasses signal processing, tone controls, yadda yadda.

The hookup? I’m guessing, I would take the pre-outs of the receiver into the crossover and the output of the crossover set at say 40hz back to the pre-in on the receiver. The main speakers at this point would see nothing above 40 hz and signals below 40hz go to the sub. The Sub has a 240 watt plate amp.

My questions:

Does this sound like a reasonable idea. Benefits? Disadvantages?
Can I pull this off with an inexpensive crossover like the Pyramid PR3000 which has RCA ins and outs?
Do need RCA or is there a converter cable that would allow me to use a crossover with XLR ins/ots and RCA connections? (I know nothing about XLR)
Will this device inject God-awful amounts of noise into the sound
Can I use an active crossover made for cars and if so do I need some sort of 12v source to power them
Auto on/off?

Anything else that I should know? Am I missing anything?

Thanks much and I look forward to any advice, tidbits or recommendations you may have!

Greg

Receiver: Yamaha RXV 2500, Homemade Sub with a Dayton SA-240 Plate amp, one pair of ADS L990 front speakers

 

[Djizasse]

RX-V2500 Pre-Outs -> Crossover -> RX-V2500 Multi-channel analog inputs?

Does the 2500 allow for a loop like this? I guess not. The receiver will play only one input at a time. The pre-outs will only pass the input currently selected. In this scenario you need one more receiver/amp/pre-amp.

As for the rest of your questions, I'll wait for input from other forum members, but for me it seems an awful lot of trouble for an awful result. An inexpensive crossover might not allow for fine-tuning the crossover points. You would probably get anomalies around that area.
A better crossover would be a Behringer DCX 2496. It would allow 3 input channels (Left + Right + Sub(or not)). You could then cut the frequencies into 3 bands: Low (for the sub), Mid (left and right) and High (left and right).
This unit has 6 outputs, but you would only need 5.

An example would be:
2500 (with bass going only to fronts) L+R pre-outs-> DCX 2496 -> front channels Amp (4 channels) + subwoofer

The DCX outputs would be:
- for the Sub:
. . . . Sub frequencies < crossover point 1

- for the front channels amp:
. . . . Front Left Low freq < crossover point 2
. . . . Front Right Low freq < crossover point 2
. . . . Front Left High freq > crossover point 2
. . . . Front Right High freq > crossover point 2

After this connections you would have to setup the DCX for the correct assignments and configure the filters for the correct crossovers. This would take a considerable amount of work.

 

[lsiberian]

Hi,

I’m wondering the practicality and potential benefit of adding an active crossover into my system. My goal would be to have the main speakers and sub sound great not just for HT but also when listening to my music with no processing (Yamaha calls it pure direct). (Currently the sub is connected to the Sub Out which I understand is only used when in surround modes on my Yamaha RX-2500)

Properly done, I’m hoping an active crossover will allow me to change the “bass out” setting for surround modes to the front speakers so I that the sub is in use not only in the surround modes, but also when listening to 2 channel stereo or in Pure Direct” where the receiver bypasses signal processing, tone controls, yadda yadda.

The hookup? I’m guessing, I would take the pre-outs of the receiver into the crossover and the output of the crossover set at say 40hz back to the pre-in on the receiver. The main speakers at this point would see nothing above 40 hz and signals below 40hz go to the sub. The Sub has a 240 watt plate amp.

My questions:

Does this sound like a reasonable idea. Benefits? Disadvantages?
Can I pull this off with an inexpensive crossover like the Pyramid PR3000 which has RCA ins and outs?
Do need RCA or is there a converter cable that would allow me to use a crossover with XLR ins/ots and RCA connections? (I know nothing about XLR)
Will this device inject God-awful amounts of noise into the sound
Can I use an active crossover made for cars and if so do I need some sort of 12v source to power them
Auto on/off?

Anything else that I should know? Am I missing anything?

Thanks much and I look forward to any advice, tidbits or recommendations you may have!

Greg

Receiver: Yamaha RXV 2500, Homemade Sub with a Dayton SA-240 Plate amp, one pair of ADS L990 front speakers

If you set your speakers all to small then your sub should play in stereo mode on most receivers.

Another option is to use the speaker line level outputs on your sub.

To use a DCX2496 you will want an AMP with XLR inputs.

Emotiva makes the XPAs with XLR inputs if you are interested in that approach.

It would improve sound if setup properly.

 

[bcycle]

You are correct sir!!

Oh crap, you are correct sir! I thought I had a pre IN on this thing so it won't allow a loop. I have had it connected via the pre-out but I don't think this receiver sends surround data out of the pre-out.

At one point I had a an a/b switchbox in the loop with input from the pre-out and the sw-out. I would have the pre-out feed the SW when listening to just stereo and would switch to B (sub out on the receiver) when in surround modes This worked ok untill the box died. (with out a crossover I just guessed at where the high freq. of the sub met the low freq. of the mains).

The bottom line in I simply want to get the SW involved when listening in normal stereo modes AND when the suround modes are running. Any other thoughts on this matter are greatly appreciated.

Thanks again

Greg

RX-V2500 Pre-Outs -> Crossover -> RX-V2500 Multi-channel analog inputs?

Does the 2500 allow for a loop like this? I guess not. The receiver will play only one input at a time. The pre-outs will only pass the input currently selected. In this scenario you need one more receiver/amp/pre-amp.

As for the rest of your questions, I'll wait for input from other forum members, but for me it seems an awful lot of trouble for an awful result. An inexpensive crossover might not allow for fine-tuning the crossover points. You would probably get anomalies around that area.
A better crossover would be a Behringer DCX 2496. It would allow 3 input channels (Left + Right + Sub(or not)). You could then cut the frequencies into 3 bands: Low (for the sub), Mid (left and right) and High (left and right).
This unit has 6 outputs, but you would only need 5.

An example would be:
2500 (with bass going only to fronts) L+R pre-outs-> DCX 2496 -> front channels Amp (4 channels) + subwoofer

The DCX outputs would be:
- for the Sub:
. . . . Sub frequencies < crossover point 1

- for the front channels amp:
. . . . Front Left Low freq < crossover point 2
. . . . Front Right Low freq < crossover point 2
. . . . Front Left High freq > crossover point 2
. . . . Front Right High freq > crossover point 2

After this connections you would have to setup the DCX for the correct assignments and configure the filters for the correct crossovers. This would take a considerable amount of work.

 

[Djizasse]

The bottom line in I simply want to get the SW involved when listening in normal stereo modes AND when the suround modes are running.

IIRC the straight mode uses the sub and the pure direct only uses the mains in full range.
I suggest you stop using the pure direct mode.