ultimate low cost FR system

[regal]

I don't think anything can compare to a fostex up to 10x the cost as far as the fostex drivers. This system I propose is not a true single driver system but I believe it makes more sense than TL or horns. The technology is there why not use it?

Start with a panasonic digital reciever SA-XR25,45,50,55,70. These are highly regarded.

Build a pair of fostex 167E's in a sealed enclosure of 8.6L F3 116hz.

Build a pair of small musical 8ohm subs. One sub under each of the fostex's (as stands.)

Set the speakers to small on the reciever with the crossover for the sub and fostex's @150hz.

From the sub out on the reciever connect a MCM 150W plate amp and connect the subs in parrallel.

It is so simple I have to ask why no one has done this?

[Dumbass]

Sounds good to me, except why send the subs a mono signal?

[regal]

I agree ideally the subs would get a stereo signal but that isn't possible with the panasonic digital recievers. I can't think of any way around it short of a preamp and then you are losing the digital path which makes the panasonic so special.

I think most recordings are mixed with bass in mono.

[cowanrg]

Originally posted by regal
It is so simple I have to ask why no one has done this?

ive seen it done, i just dont have any links. it seems to me that the FR is full of a lot more "purists" who dislike subs. they opt for TL's with limited range.

personally, i think building a pair of musical subs would blow the "low cost" budget by themselves. i have yet to hear an inexpensive subwoofer (of the 8", 150W variety) that sounds a whole lot better than a a good full range tower speaker.

[Dumbass]

Originally posted by regal
I agree ideally the subs would get a stereo signal but that isn't possible with the panasonic digital recievers. I can't think of any way around it short of a preamp and then you are losing the digital path which makes the panasonic so special.

I think most recordings are mixed with bass in mono.

Prevailing "wisdom" is that bass freqs contribute nothing to the stereo effect, I have heard recordings that disprove this.

Only on a 5.1 format would bass freqs be mixed to mono.

Do the Panasonics have tape-outs? Use those for the subwoofers. Run the FE167E full range.

But I agree, having two good subwoofers will not be economical. Maybe just run one.

Or perhaps a better solution is to put the FE167E in MJK's tapered TL design (originally for FE164). Bob Brines has plans for a folded version on his web site. Then cross over to a single subwoofer at a much lower frequency. IIRC not every commercial subwoofer would allow a 150Hz crossover point.

BTW I think the overall concept (full-rangers in sealed enclosures, plus actively amped stereo bass units) is a great idea, just not necessarily the most economical once you factor in the stereo subs.

[cowanrg]

partsexpress has a buyout of 8" DVC drivers that look "ok" for like $14 each. if you did that, a 150-watt plate amp for each, run them line-level out (not sub out), and cross them over with the fostex's, you might have a decent full range system on the cheap. however, i would opt for just doing a TL for the fostex's and having less bass, but much better bass. i cant imagine a $14 driver with 150-watts will be that great.

[regal]

I have done some testing with my Fostex 127E and they really perform better when you actively cross them over 100hz or higher. These drivers are xmax limited so the higher you cross them over the better they sound.

I don't think the tape pre-outs on the panasonic reciever are fading (same output regardless the volume setting.)

[cowanrg]

well, the LFE (sub out) channel should be sufficient. you would just need to split it into two channels. you wont maintain stereo bass info, but since you are using the xover in the receiver, it shouldnt be a big deal. especially if you keep the xover point low, so you dont run into directionality issues.

[regal]

Yes I think I could go up to 150hz.

[cowanrg]

instead of using the panny receiver, why not just build a complete 2-way active system? if you are doing powered subs, all you need to do is power the fostex drivers. they are pretty darn efficient, so that should be an issue. and, most of the plate amps out there give a line level output that can be used as your crossover. they have line in and then a line out that cuts the bass frequencies.

so, along your idea, you could use the output from a cd player to a passive volume control (or active) to the subwoofers, then out to the monitors, which would be powered with a gainclone or even a sonic impact T-amp or whatever.

IMO, some cheap powered monitors with powered subs hooked right up to a cd player could be the ultimate cheap FR system.