Cornwalls Bi-Amping Options

[AXLEHOUSE]

Hello to the Klipsh Community and thanks in advance for your input.

I am considering options for running a pair of vintage Cornwalls with two amps. I have done some internet searches and read some other threads but have not come across a configuration like the one I am considering. Most of what I have come across is bi-wiring, series or parallel bi-amping with an active crossover etc. I appreciate that big benefits can come from using an active crossover (and also that this can require more fine tuning) however right now I am not interested in converting to an active cross over. What I have to work with are two Yamaha M-65 power amps. I am thinking of running one amp for each speaker by splitting one channel out of the pre-amp (right for example) ® with a Y-cable, into two ®®. Having these two ®® go into the R&L inputs of the power amp. Having the R&L outputs of the power amp go speratly into a split internal speaker crossover (configured like a Klipshorn). My logic for this configuration is that (along with the mid and high) the power supply in each amp will only be powering one woofer in each speaker as opposed to one amp powering both R&L woofers and another amp both R&L mid and highs as done with other configurations. My objective is to improve bass and make the most of the 15’s in these boxes while using the amps two amps I already have. I look forward to your response, thanks Gregg (P.S. I grew up and have lived with these speakers most of my life).

[russ69]

Axle,

You can run two amps but in this case I don't think you would gain that much. Doubling your power will only give you 3db, not that much. Real improvements from a bi-amp set up is having an amp that's really good for the mids and another that's good for the bass. I checked out your amp and it cannot be bridged into a mono amp (the best way to use two identical amps) so you are not gaining that much.

From what you say (you want more bass), I'd buy a real powerhouse amp. A quality, 200+ watt a channel one (one that takes two guys to lift!) or I'd get a sub.

Thanx, Russ

[DrWho]

What you propose can work, but it will require a modification to the
xover in the cornwall (not a very difficult change to make either).

However,
I would be extremely surprised if you could hear the difference without
knowing which one you were listening to. In fact, you're going to make
things slightly harder on your preamp in hopes that the power supply in
your amplifier is inadequate. If the power supply is inadequate, then
just get a better amplifier. Making things harder on the preamp is not
trivial either - in fact, lowering the load impedance it sees will
raise the LF corner of your preamp by an octave (assuming there's a dc
decoupling cap in series, which should be the case). So in that regard,
it'll actually give you less bass.

The only thing I could see
doing with the equipment you have on hand is to get rid of the xover
between the woofer and the amplifier - that way you can gain the
benefits of dramatically increased electrical damping. This will go a
long way in tightening up the bass and giving it more authority.
However, you will need to find a way of low passing the signal before
the amplifier so that you can properly integrate the woofer with the
rest of the speaker. There are three options to achieving this: active
digital xover (which you don't want to do), active analog xover (which
I'm not sure if your'e against or not), or a passive filter. The
passive filter will require some careful engineering if you don't want
to introduce all sorts of unintentional behaviors - something I wouldn't recommend, but it would be the cheapest approach.

I know I'm not being super supportive of the idea, but that doesn't
mean
you can't just try it out for yourself - it's pretty much a free mod to
try anyway. The xover mod should be as simple as moving some wires
around - do you know which xover you have, so we can look up the
schematic?

Btw, welcome to the forum.

[AXLEHOUSE]

The crossovers are original B2’s. I am very capable with mechanicals but limited with the more technical aspects of electronic theory beyond power, load & ground etc. One of the questions I have with the power supply in the Yamaha SS M-65 amps is whether the supply is one big supply (for both R&L channels), or is the supply more like two separate power supplies in one chassis (one for R & one for L)?

My concerns for not using an active crossover are I know little about this and am working within a limited family budget. While the ultimate goal is great sound I also like the continuity of working with the equipment I have had for years. I can tweak to a degree, but I am not a big component swapper. Other suggestions are welcome, Thanks again.