[markC]

The little girls riding their bikes + your OB's in the basement sounds like you'll be moving them upstairs sooner than later.

[-Richard-]

Hi Jeff and mcgsxr ~

It does seem like those thin little EL 84 darlings really do make wonderful love with the OB's... don't they!

A love affair that brings out what the OB's do that is so uncannily magical!

I have been through so many tube SET equations... they all sound quite marvelous... but Sam's EL 84 circuit design in the Heathkit does something with the combination of the Visaton and Eminence drivers hooked up in parallel that moves into an entirely different dimension of sound... hard to describe... something so intrinsically alive that it easily rivals the "real thing"... my work is over for now... my OB's and the triode version of the Heathkit with EL 84 tubes turns on all the musical lights... and takes Deb and I into a zone where the emotions can fully come alive.

Warmest Regards ~ Richard

[hurdy_gurdyman]

I had  a Heathkit SA-2, which is about the same circuit as the AA-151  but in a more compact cabinet. The sound of it was wonderful. Wish it was still working, but it had an output transformer short out. It was the purist sounding tube amp I'd owned up to that point. Never had a chance to use it with my current open baffles (it died just before I discovered them), nor did I ever have a chance to compare with my current TAD-60 EL34 amp. Wish I could try one today and compare.

Dave

[BigRick]

So on OBs the amp makes a big difference?

All this has me thinking about OB design is the a way to have a cross over in the setup, most OBs I have seen are single driver and subs, could you ad a crossover and have a larger low frequency driver, or even an open baffle tweeter?

[doorman]

Quality amplification with any speaker makes a difference!
Best, Don

[hurdy_gurdyman]

So on OBs the amp makes a big difference?

All this has me thinking about OB design is the a way to have a cross over in the setup, most OBs I have seen are single driver and subs, could you ad a crossover and have a larger low frequency driver, or even an open baffle tweeter?

An OB can be made of the same type of driver arrangements and crossovers that boxed speakers use. You can have fullrange, coaxial, standard two, three or four way, etc. You can combine dynamic cone woofers/mid woofers with high frequency compression horns, cones, ribbons, domes or piezo drivers. They all work, and they all have different strengths and weaknesses.

Dave

[-Richard-]

Hi Dave ~

Yes... yes... nice overview... and isn't it wonderful that one's designs can take whatever direction your creative impulses set there course upon to explore!

Warmest Regards ~ Richard