JD,
The only difference between the 3000 and the 4000 is a 12" driver vs. 10" one. Naturally it can go a little deeper in the bass and louder too.
The Dynaco 400 is exactly what these speakers prefer.
As you may have noticed the OHM website is not big on handing out specs on their products (they weren’t 35 years ago either).
But to their credit they emphasize room size to pick the right speaker, which in all probability is the right way to pick your speakers.
You mentioned you had Walsh 7's in the 70's. You are most likely referring to the Walsh F which was a true Walsh design (one driver and a true omnidirectional) unlike the modified Walsh designs that started in the early 80's (gen 2) which were considerably more efficient (but still fairly inefficient) that had the main driver + super tweeter arrangement. These, and all subsequent Walsh models, also featured damping material (which OHM calls 'Tufflex') applied to the rear of the main cone driver which attenuates rear sound propagation by -20 db.
The only difference between the 3000 and the 4000 is a 12" driver vs. 10" one. Naturally it can go a little deeper in the bass and louder too.
The Dynaco 400 is exactly what these speakers prefer.
As you may have noticed the OHM website is not big on handing out specs on their products (they weren’t 35 years ago either).
But to their credit they emphasize room size to pick the right speaker, which in all probability is the right way to pick your speakers.
You mentioned you had Walsh 7's in the 70's. You are most likely referring to the Walsh F which was a true Walsh design (one driver and a true omnidirectional) unlike the modified Walsh designs that started in the early 80's (gen 2) which were considerably more efficient (but still fairly inefficient) that had the main driver + super tweeter arrangement. These, and all subsequent Walsh models, also featured damping material (which OHM calls 'Tufflex') applied to the rear of the main cone driver which attenuates rear sound propagation by -20 db.