Right then, following the tuneage on display at Waggle I want me some more bass. Nowt too loud, just richer.

Talking to Will he suggested a tri-mode / tri-way crossover to allow my stereo amp to run a sub-woofer. But I'm struggling to find one.

According to diagrams in the owners manual, the amp does allow you to run a bridged subwoofer (with crossovers).

Thing is, I'm confused as hell. Can't really get a handle on what I need and have little knowledge of ohms, capacitance etc.

Just want to run a compact sub using the existing kit I've got.

Recommendations of kit / web sites gratefully received. On a vvvvv tight budget, so any second hand kit you've got knocking around would be even better.

Cheers doods!

any pictures of the amp you have now? terminals and switches and stuff...

what head unit are you using? Mine has an specific sub outlet that looks like a normal audio plug at the back. I don't have a sub atm, got 2 x 5" Vibes fitted in a meter long tube under the back seat. Works a treat... although passengers tell me the back seats vibrates a little

basically i think tri-mode is to do with ohms and giving you an extra "bridged" channel.
IIRC tri-mode enables 2 speakers and a sub to be ran off the same amp.

I used to run a 4 channel amp with 2 speakers and a sub with 2 channels bridged rather than tri mode. Only because I had the extra channels to play with.

maybe this can help explain?
http://www.caraudiobook.com/car_audio_a ... ifiers.htm

I'll have to have a look at your amp to be sure but I am sure we can hook you up with some tunes!

pictures shows both ends of the amp, inputs and outputs.



you can see wheres its tri-moded to run 3 items off 2 channels.

(I am guessing you have a 2 channel amp BTW?)

Tim, here's a link to the pdf of the owners manual for my 2 channel sony amp.
http://pdf.crse.com/manuals/2586733111.pdf
It's currently feeding two 6x9's -
Head unit is sony cdx-gt212. It has no seperate sub output.

seems easy enough...



Would have to read the rest of the PDF some time but it can be done. Need to check the ohms, Watts etc...

Cheers geezer. There is a table of crossover values that means sod all to me.
What are the C1/C2 (capacitor) & L (coil) all about?
How would installing a sub set up like this compare to fitting an active sub d'ya think?

Yup tri-mode is pretty simple and it is a feature that is inherent to most two-channel amps on the market, providing you get a crossover to balance the load on the amp and get the right impedance and cutoff frquencies.

Kenwood do (or did) an neat little tri-mode crossover that you just plugged inbetween your amp and speakers, I have one in Mavis. I can't remember the model number but I might dig out some early kenwood catalogue porn and have a look.

However, you do lose a little bit of headroom with tri-mode and when you are giving it some beans (in the beer tent after hours at a camp for example) you do get some clipping unless you ease off the volume for a bit.

TBH though, for the cost of a crossover and passive sub you are well on the way to the price of a little active sub anyway so this might be the way to go. Kenwood, Pioneer, blaupunkt and Alpine all do little under-seat active tubes or boxes which will just plug and play from your head unit, either line-out or speaker-level outputs. Take a look here for info:
http://www.caraudiodirect.co.uk/enclose ... 9l2cus0b15

The Kenny or the cheaper Pioneer one would complement your set-up well.

It would appear from my web trawling that those tr-mode crossovers are like hens teeth these days. I do like the idea of the neat underseat options - just gotta find one at a reasonable price (well under £100).