[Pzwief]

Hi All:

I run a pair of Paradigm Studio 20v4 with a Paradigm Monitor Sub 8.  Studio 20 will go down to about 54hz.  Would I benefit from a high pass filter so the lower frequencies never get to the Studio 20s?  Some say a high pass filter will relieve the Studio 20s from having to play the lower frequencies.  Others say it's not needed because the Studio 20s simply won't play frequencies below its range anyway.

I just finished building my own Hypex ncore nc400 monoblocks & am looking for a balanced preamp for them.  Was targeting a used Bryston BP 20 or 25.  Then I saw the Emotiva XSP-1 that includes a high pass filter.  Your thoughts please.  Thanks.

[jparkhur]

Just build one...

http://www.audiocircle.com/index.php?topic=126480.msg1334300#msg1334300

[mikeeastman]

I just soldered the caps on the input of my Ncore, less connectors.

[jparkhur]

I just soldered the caps on the input of my Ncore, less connectors.

Mike is right, but if you sell your amps or use different speakers, you would have to change the caps out?    Either way it works.

JP

[*Scotty*]

if you are playing back music from a computer source you can use jRiver via its DSP Studio, to put in a low frequency shelf filter at the 3dB down point you want and get out of doing it in hardware. You also avoid the small, but audible signature of having the cap in the signal path.
Scotty

[jparkhur]

if you are playing back music from a computer source you can use jRiver via its DSP Studio, to put in a low frequency shelf filter at the 3dB down point you want and get out of doing it in hardware. You also avoid the small, but audible signature of having the cap in the signal path.
Scotty

Yes, but how are you going to output the lower end if you now cut all signals out of the computer?   Is there a dual out way?   

[*Scotty*]

Good question, it may be possible using the multi-channel room correction in the DSP Studio, but it will require delving into jRiver FAQ wiki.
I have only a 2 channel system and haven't used this feature of the software. It may require a multi-channel processor to implement however.
Scotty

[ebag4]

If trying to hi pass a balanced input I believe you have to put a cap on the + and - line, do you cut the capacitance in half?  For instance if I want to hi pass an amp with a 48k input impedance at 165Hz, do I use a .2uF cap on both legs or do I use a .1uF cap on each leg?

Thanks,
Ed

[Davey]

You don't mention what type of input stage you have.  That will make a difference.

But generally, you can consider the + and - inputs "separate" from each other for this type of calculation.  Each would have characteristic load resistance referenced to ground, and that would be the value you would use to calculate a series capacitor.

Cheers,

Dave.

[Folsom]

What about the type of output of source/pre? The reactance of the capacitor isn't desired, nor added sonic signature. But those might be easily overlooked for the benefit of having a crossover. Class A no feedback?

The biggest benefit to active is often a lack of crossover, compared to easing the mechanical properties of a woofer. That offers overall sonic improvements in many areas with many amplifiers. But do you do it at the digital level or analog?

Multiple digital outputs is probably ideal, going into multiple DAC's... as opposed to using someone's hooky ADC to DAC lessening the quality of your initial DAC or vinyl.

[ebag4]

Thanks guys, I'm considering driving a modulus-86 amp from an Auralic Vega using the balanced connections of each.  The modulus has an input impedance of 48K.

Thanks,
Ed