Bottlehead for deaf loudspeakers

[Paul Birkeland]

I believe Harbeth Monitor 40 can be bi-wired/bi-amp?

Biamping a speaker in this manner isn't going to buy you extra output.

[Doc B.]

PB is right here as you are still only running 16W thru the woofer, which eats the power. That said, you might buy a bit of clarity from the tweeter as you push the level since the tweeter would still be driven cleanly by its amp as the woofer amp went into distortion. I'm thinking another possibility with four amps and thus 32 wpc would be to not biamp but rather wire each output transformer for 8 ohm output and connect the secondaries of two amps (hence four output transformers) in series/parallel. Hmm, do I have enough Kaijus around to try this?

[Jamier]

Maybe it's time for the BIG single ended amp that was mentioned a couple of years ago, as a possible new product, on the survey.

[Phippers]

I should also point out that the Harbeth Monitor 40 is a 3-way design.... so tri-amp ? 

But yes, the woofer would probably still not be (as) happy (as the mid and tweet) with just 16W.

Out of interest, the Harbeth Monitor 40 was designed as a drop in replacement for the Rogers LS5/8 in BBC studios. The LS5/8 was a 2-way design and was driven by a BBC modded QUAD 405 to bi-amp the LS5/8, with frequency splitting and eq performed at line level as part of the BBC mod.

IIRC, Harbeth went on to use QUAD 405's to demo the Monitor 40, one 405 per loudspeaker - I think these would have been wired as monoblocks with the standard crossover in the Monitor 40.

I like the series / parallel idea though Doc ! - the big Kaiju monoblock

[Paul Joppa]

With four channels of Kaiju, it would be better to wire them each for 2 ohms and put them all in series to feed 8 ohms.

[Doc B.]

Yup that does make sense.