Get some B & W's !!! Subs excellent. More pricey but worth the extra spend

Which one?

Following Andy's recommendation (thanks Andy) I actually bought a BK Electric Monolith. Huge thing - 47 kilos with the build quality of a large REL but about half the price.

http://www.bkelec.com/HiFi/Sub_Woofers/monolith-df.htm

If your on a budget, the BK Gemini would be a good option... if you can go higher... try the more expensive ones, or if you really want refinement, got for a REL Strata III if you can find one (they are a closed box design, that I prefer... the new strata V is a ported one)

PLease excuse my lack of knowledge, but how do you actually connect a sub to your amp? I have a nad 372 amp and was wondering if anyone could help me figure this one out, with maybe a link to a site with info and possibly a diagram, thanks.

There are two ways of doing it. You either connect it to preamp sockets at the back of your amp (if your amp has them) to the phono socket(s) on the sub or you wire from the speaker terminals on the amp to the 'high level' connection on the sub. This 'high level' connection is usually a speakon socket.

Usually there are instructions that come with the sub.

Thank you very much for your help, i'm purchasing the mordaunt short avant MS 309 sub to connect to the nad 372, the sub has a sub lead that comes free with it as a special offer, so i'll be using that, the lead is the qed p-sw 3m.My amp do actually have preamp sockets at the back, so i need to set it up by plugging the phono sub lead into the left and right of the pre out 1 sockets of the amp? out of the 2 different ways to set it up, is there much or any difference in quality? heres a pic of the rear of the nad amp if this helps at all.cheers! http://www.superfi.co.uk/images/c372_rear_1200x416.gif

REL recommend that you connect to the speaker terminals where this is possible.

I personally don't do this because in doing so, you connect to the L and R red speaker terminals and then you connect the earth to just one of the black speaker terminals - this causes problems for digital amps like mine. Your NAD amp would be OK though because it's a conventional linear design.

If you're using the RCA sockets, yes; both preamp sockets to either one or two of the RCA sockets on the sub.

If you haven't bought yet, I would seriously recommend the BK. The more I looked in to it, the more really good sub designs from other companies I found to have come from them. They do OEM for MJ Acoustics as well.

Too late, it's being delivered tuesday, i'm still unsure if i need to use the volume control at the back of the amp, i think i read somewhere you do, and do i take out the binding posts connected from the main sockets to pre out 2? or leave them in and just rig it up to the L/R pre out 1? sorry chris.

I'm assuming you're using the phono sockets only.

There will be a volume control on the sub. Use that. The volume control on the back of the amp is a bit misleading - few amps have one of those.

Use Pre Out 1 to the phono socket(s) on the sub. If you disconnect Pre Out 2 from Main, you probably won't get any sound at all as that is the link between the preamp and power amp in your NAD.

How many phono sockets are on the sub?

Sorry about the delayed reply, i only received the sub today.There are two sets of phono sockets on the sub, i have a sub lead in the right socket of the sub to the pre amp 2, i made a mistake, it's the pre amp 1 that has the links to the main sockets on the amp.I need to get the balance right so the sub enhances my main speakers, which i haven't had time to do yet.Another thing i really don't understand is the notch filter, i have no idea how it works, although i do know it's for easier room placement.I'm also not sure if i have the sub lead connected in the right pre amp, 1 or 2? anyways if you can guide me i would be most grateful, cheers!

Preamp one and two are the same. It doesn't matter as long as you don't remove the links on the amplifier between pre and main. Make sure you attach both left and right though.

Yes, the notch filter is for room matching. Why not contact Mordaunt for a proper explanation http://www.mordauntshort.com/support.php.

Make sure you tell us whether it's any good.

The sub cable i'm using only has one input plug either end? so i've connected right to right.Thanks for the link, i will ask them if they can send me some instructions, as the sub i purchased didn't seem to have any info on the notch filter system, i'll let you know how it goes. cheers again for the link.

You will definitely need either two cables or a two in to one adapter to blend the left and right channels together before they reach the amp. The alternative is a two in to one adapter - otherwise you will only be subbing one channel.

If you have an home cinema amp, they usually have a dedicated single sub output and this is why you were only given one cable in anticipation of this.

Could you tell me what effect that has on the sound comming from the sub? Is there a particular lead that you would recommend in the 20 to 25 price range, or do you think i would be better off buying another QED Qunex P-SW to match the cable i'm already using?

Use the same cable. Try ; http://www.hificables.co.uk/ProductsList/mcs/CategoryID/2378/GroupID/707/CatName/Subwoofer%20Cables/v/f5480810-71d3-4127-b969-6dba5ff33cc1

They're reliable and they discount a little bit.

Thanks, i just ordered another cable.Could you tell me what effect using a stereo cable has on the performance of the sub?Cheers!

You have to merge the left and the right channels otherwise not every sound gets to the sub. Effectively only the sounds from the left or the right channel would go to the sub if you only use one lead.

Using two cables makes sure that both left and right are correctly merged so that the sub is working on all of the sound and not just one side.

Got the other lead rigged up now, i'm still waiting on Mordaunt Short to get back to me about the notch filter system.I should have received a disc with the sub to help me tune the filter but did not, so i'm hoping that Mordaunt short will send me one.Is the filter system for the sub to be placed pretty much anywhere but it will still sound as though its comming from the main speakers?

So I gather.

Once you've got it plugged in right, it's pretty much down to trial and error anyway.

The idea is that you shouldn't be able to distinguish between where your speakers end and where the sub starts to kick in.

When I first started with my sub, it took about a fortnight of small changes until I had it properly integrated.

The Mordaunt disc is supposed to be quite good but you could manage without it; just use as many different types of music as you can.

It seems i have a problem, i turned on the sub and it went to the green light for a second and then completely lost all power.I checked the fuse in the plug and that was fine, so it's obviously internal.I've had the damn thing a week and this happens, it's an ex display model, but i didn't think that would be a problem, it looks as good as new.