[enemigo]

I've been reading a lot about crossfeed lately, so I tried to build the bass enhanced crossfeed:

I seriously doubt I managed to get it to work. It sounds very thin an sharp, no bassenhancement here, not much low mids either. And I've tried plugging it in both ways

I built the crossfeed without bass enhancement too, and that was even brighter.

Here are the Jan Meier drawings:
http://headwize.com/projects/showfil...meier2_prj.htm

What's wrong? Am I grounding wrong? The bass enhanced filter have Gnd in and out connected after the 47uF cap. On the other one, the groundwire goes directly from jack in to jack out, without beeing connected to the crossfeed circuit.

Btw: I use 220nF rather than 200nF for the bass enhanced circuit as I read somewhere that would be ok.

Thx
Knut

 

[Woody]

There is one obvious difference between the two drawings. You have a drawn a 47uF centre grounded cap, Jan opts for a 47nF.

But as you say that the standard crossfeed doesnt work either then I guess thats not your problem.

Are you inserting this between the source and the amp or the amp and your headphones ?

Out of interest what amp and phones are you using ?

 

[enemigo]

Da*n, I used 47uF. That probably explains a bit. The other x-feed have these component values: R1=4k7, R2=19K and C1=100nF.

I'm using the x-feed between the source and a cMoy. Headphones are Alessandro MS-1's at 32ohm. Might be an impedance problem?

K

 

[__redruM]

Also note, crossfeeds rarely give night and day differences. To test them you really need a song which uses one side only. Example Track 1 on Kill Bill 1 Sound track "Bang Bang".

 

[rickcr42]

Quote:

Also note, crossfeeds rarely give night and day differences. To test them you really need a song which uses one side only. Example Track 1 on Kill Bill 1 Sound track "Bang Bang".

or an early Beatles CD will also work well

 

[bg4533]

For testing crossfeeds I usually just unplug one channel of the input. With crossfeed off you should hear nothing from the headphone for the unplugged channel. With crossfeed on you should hear a little.

 

[PinkFloyd]

From Left input to left output it should measure 2K
From Right input to Right output it should measure 2K

From left input to right output it should measure close to 6.35K
From right input to left output it should measure close to 6.35K

I use 220nF in place of the 200nF

More details here

 

[Woody]

Quote:

Originally Posted by enemigo Might be an impedance problem?

Well it crossed my mind, but I cannot see how or why in this instance.

I think the others suggestions to try one channel etc seems a good idea. Just to troubleshoot a bit. It certainly has all the hallmarks of a dodgy connection somewhere. Have you also tried with another piece of source equipment ?

I personally wouldnt want to go sticking RC networks any where near a pair of MS-1s any way, but thats just me

 

[PinkFloyd]

Quote:

Originally Posted by enemigo Da*n, I used 47uF. That probably explains a bit.

That explains it "all" use a 47 nanofarad and not a 47 microfarad and it will work fine whatever the headphone impedance. ground all 4 of the Phono socket earth tags to the ground side of the 47nF

Pinkie.

 

[enemigo]

Quote:

Originally Posted by PinkFloyd That explains it "all" use a 47 nanofarad and not a 47 microfarad and it will work fine whatever the headphone impedance. ground all 4 of the Phono socket earth tags to the ground side of the 47nF Pinkie.

Thanks for replies everybody!

4 phono socket grounds? That confused me a bit. There's just one ground for input an one for output!?

BTW: I'm not using my MS-1's on "untested" equipment

Knut