[mgrewe]

I was thinking about making my own crossfeed filter based off the basic Jan Meier design. http://www.rock-grotto.co.uk/x-feed.htm# But since I'm new here, I'm not really sure if it would make a difference to my CD setup.

I have a headroom total bithead amp that I use with my comp and ipod, and I prefer listening with its crossfeed most of the time. But I don't use the amp when I listen to my cd player because it has a pretty decent hp amp built in. I want to add crossfeed to my cd setup but I'm not sure if I should just plug in my bithead and use that cf, or build the Jan Meier.

Plus, if I were to make my own cf, I would change the RCA in/outputs to a 1/8" jack (input) and a 1/4" plug (output). That way I could plug my headphones into the cf, then the cf into the hp output on the cd player. (Would this hurt sound quality?)

If anyone has thoughts or suggestions that would be awesome. (I also don't have a large checkbook b/c im still in highschool)
Thanks

 

[r_d]

A passive filter will attenuate the signal, but this shouldn't be a major issue if your amp can drive it.

I say go for it. The parts are dirt cheap, and if you're really impatient or short on cash, you can probably salvage them from junk electronics. I've found that old modems are a good source for polypropylene capacitors. Maybe not the best quality in the world, but when you only need a 1uF polypropylene capacitor, it beats paying $8 in shipping on a $2 part and waiting a week.
If it turns out that you don't like how it sounds, it's not like you really lost much. You just learned how not to build a crossfeed filter.

 

[Earwax]

Funny that you brought this up just now. I've been revisiting the crossfeed I built several years ago and comparing to the software crossfeed in Rockbox for Sansa E200.

I built the Meier enhanced bass crossfeed HeadWize - Project: An Enhanced-Bass Natural Crossfeed Filter by Jan Meier. Actually I made 2, one with RCA jacks in and out and a second with captive mini stereo plugs on input and output. I plug the input into my MP3 player and the other into my cmoy amp.

The attenuation is very slight, unless you're right on the edge of usable volume now, I don't think it will present a problem. The effect is also subtle and most appreciated with solo vocals where it pulls the voice together to a single point. In general, I still don't think I'd bother with crossfeed for instumentals, but may start using it again for vocals.

Right now, I'm liking the Meier crossfeed over the rockbox version, but reserve the right to change my mind with further listening.

 

[kvant]

Quote:

Originally Posted by mgrewe /img/forum/go_quote.gif Plus, if I were to make my own cf, I would change the RCA in/outputs to a 1/8" jack (input) and a 1/4" plug (output). That way I could plug my headphones into the cf, then the cf into the hp output on the cd player. (Would this hurt sound quality?)

Hurt sound quality? It pretty much would not work as intended at all. The filter from the page you linked is supposed to have its inputs connected to a low-impedance source and its outputs to a high-impedance next stage. In practice it means that you put the filter between RCA jacks (or headphone out) of the CD player and a headphone amp. You cannot connect headphones directly to the outputs of the crossfeed filter as they don't represent a high enough impedance. Unfortunately, the page you found does not say this, since it offers "...no technobabble, no confusing schematic diagrams..." and therefore no understanding of what you would be doing if you followed their instructions. Too bad.

Before you start building, I suggest you do a little more reading on the subject. Some resources:

1. projects "crossfeed filter" and "headpamp" described on web-site of Meier audio
2. projects "An Acoustic Simulator for Headphone Amplifiers (Chu Moy)", " A DIY Headphone-Amplifier with Natural Crossfeed (Jan Meier)" and "The Lindesberg Portable Headphone Amplifier with Crossfeed (Toni Kemhagen)" that you find in the library at Headwize

From these you get a better idea on the function and intended applications of crossfeed filters. BTW, the Chu Moy's article discusses a version of the filter that would drive headphones directly, but if I remember correctly, it was judged as an inferior option.

Or, you can forget all this techno babble, connect your bithead to RCA jacks of your CD player, switch its crossfeed on and be all set.

 

[mgrewe]

Awesome, thanks guys.

And Earwax, when you built your cf with the mini stereo plugs, did you connect the ground to just the input, or did you connect the ground to both input and output?

 

[mgrewe]

Alright, thanks kvant. Your post just popped and it was pretty helpful.

Quote:

Originally Posted by kvant Hurt sound quality? It pretty much would not work as intended at all.

I read somewhere where they said sq would suffer, but I didn't know for sure.

I'm going to build a crossfeed anyway, just to have some fun with it, but whether or not I use it doesn't bother me.

Also, does any know if the amplifier on the marantz cd 5003 is better or worse than the total bithead?

 

[Earwax]

Quote:

Originally Posted by mgrewe /img/forum/go_quote.gif Awesome, thanks guys. And Earwax, when you built your cf with the mini stereo plugs, did you connect the ground to just the input, or did you connect the ground to both input and output?

in- and out-