Whamopipe

[MIKET]

Just finished my latest project a pair of speakers I call Whamopipes, a cross between the Bottlehead Whamodynes and a Voight pipe. Each pipe is filled 1/2 lb. of lambs wool. The 4 MCM 55-1870 drivers wired series-parallel for an 8-ohm load through a 0.36 mH choke and a 2uF Polypropylene Cap is in series with the Peerless DT 105 H Tweeter, the bottom 10 inches of the Pipe is filled with concrete. They are still braking in on my back porch, one thing of note they don't sound boxy, more open like a pair of electrostatics. Each Cabinet weighs 70 pounds.

[sreten]

Hi,

Just a suggestion :

Investigate Baffle Step Compensation and experiment using
the outer two drivers as 0.5 way drivers, i.e. rolled off early.

/sreten.

[MIKET]

Wanted to crossover the tweeter lower but to do that required a higher order crossover. Used a third order at 3500Hz for the tweeter 4uF, 0.27mH, 11.8uF. The woofers were naturally rolling off at about 3 K along with the 1st order at 3500 Hz seems to blend the best. Checked it out with Diana Krall "Girl in the Other Room" and Solomon Buke "Don't Give up on Me". The speaker sounded balanced with the new crossover. In the past it was a little thin with female voices, probably due to the slight dip between 3-5 KHz. That seems to be gone now.

[MIKET]

See Below for a mechanical drawing of the cabinets

[MIKET]

See below:

[diydave]

Cool, I had considered doing a voigt pipe config but went with standard Whamodynes:

http://www.coquet.info/ht/

[UNDERSTANDIN]

I'd like to know what you guys think of the MCM 55-1870.
They are on sale again.

[diydave]

I think you can probably get better drivers now for a similar price. I remember reading about the 55-1870 almost 10 years ago.

If you can get them for cheap, like $5-$7 per driver, they'd be ok to play with. That being said, they still sound pretty good with the right tweeter and in the right cabinet they can put out some surprising bass.

[MIKET]

I have used the 55-1870 in several designs, the choice of crossover and tweeter is critical. With my SE tube amp, I would need to spend a bundle to sound better, IMHO. I am attaching the whamopipe diary to give you a little more info.