How to connect speakers in both stereo/mono?

[revans]

First up, I'm not sure if this shhould be in electronics or not, so sorry if it should be.

Hey guys, I'm in the process of buying speakers/amp/stuff so I can have a go at putting together a boombox type thing. Because I'm way down under in New Zealand, shipping costs are horrendous so I'm going with speakers from this ebay store (free shipping!): http://stores.ebay.com/AudioTek-Shop

Previously I've been looking at using two full range TBs (these ones: http://cgi.ebay.com/ws/eBayISAPI.dll...link:middle:us OR these ones: http://cgi.ebay.com/ws/eBayISAPI.dll...link:middle:us), but I'm now also considering a 2.1 sort of setup using a woofer/mid thrown in there (this one: http://cgi.ebay.com/ws/eBayISAPI.dll...link:middle:us OR this one: http://cgi.ebay.com/SEAS-H702-T14RCY...742.m153.l1262).

I'm using an Amp6-Basic amplifier which outputs stereo sound so I'd like to wire these three speakers so that one FR takes the left stereo channel, the other FR takes the right stereo channel, but the woofer takes both channels. I don't know how to do this, so it would be great if someone could point me in the right direction or explain how this could work. Thanks.

[richie00boy]

You need a summing circuit to create the mono signal, then a low-pass filter to cut off the midrange and up. The sub-woofer controller on my website would do the job. www.readresearch.co.uk in the projects section.

[sreten]

Hi,

You invert one channel input and then connect one of the
speakers in inverse phase at the output = back in phase.

But you now effectively have a bridged stereo amplifier.

Connect the "sub" via an inductor across both channels.

Only works with amplifiers you can bridge, think the AMP6
cannot be bridged, you may have to use a chip-amplifier.

/sreten.

[revans]

Thanks sreten, I'm definitely going with an amp6basic so I guess that's not going to work for me. Oh well, thanks anyway.

[Dr.EM]

Looks like a good project . I don't know if I should mention this as there may be a legitimate reason why, but I ordered some PGA2310 chips from that store months ago and they still arn't here. I would be very cautious ordering expensive drivers. Has anyone else here used that ebay store? Would be interested to hear peoples experiences.

[revans]

Yeah, you've made me a bit cautious now. But they've got that power seller thing and they've got a lot of positive feedback and you can't fake that (or can you?? I wouldn't know).

[pelanj]

Or maybe just use a dual voice coil driver with a standard crossover. That makes L+R bass "for free".

[Dr.EM]

My brother warned me before using that seller but I went ahead as it was not very expensive and much better priced than from Farnell or somewhere in UK. Apparently you can fake feedback. I don't want to say anything outright as I haven't actually contacted the seller about it yet, but don't have much hope for them arriving now.

[revans]

Dr Em: Did you try and get reimbursed? I trawled through Audiotek's feedback and found that apparently if the price is too low they often say the item has been "lost in shipping" and will just reimburse you.