If it was tight with the Anthem, then the boomy bass issue would foremost be the 8B's higher output impedance and therefore, its damping factor. Tube output stages (especially vintage ones) with a high output impedance translate into bloomy loose bass unless they have an extensively wound transformer with 4-ohm taps.
04-22-12: River251
It was tight with the Anthem. Only once or twice did I notice any boominess. Plus they did not put the spikes in, and it was a foot from the back wall. I pulled it out 2 more feet but not much difference. Probably a 15x15 listening room. Think it might be OK?
The 15x15 room would be particularly problematic, as the resonance of a 15' wavelength would be doubled (at least) compared to a room with only one 15' dimension. 75 Hz puts out a 15-foot wavelength. That splits the difference between the D and Db not quite 2 octaves below middle C on a piano. If your room is not square and has different dimensions than the audition room, you can just about count on any resonant modes being elsewhere, and probably not as strong. 3' from the wall *plus* spikes should make a significant difference.
I plan to post elsewhere to get help finding the most well-recorded jazz double bass CD of all time, and the best-recorded jazz drum kit.
Two of the best acoustic bass recordings I've heard (and have) are Modern Jazz Quartet's "The Watergate Blues" on their "Echoes, The Modern Jazz Quartet Together Again 1984", also available on "The Best of the Modern Jazz Quartet," a CD which is still in print and available from Amazon. Watergate Blues is an extended bass solo by Percy Heath, well mic'd and recorded. It's one of my gold standards for plucked acoustic upright bass.
The other is Christian McBride's well-recorded opening to Diana Krall's "All or Nothing at All" on her "Love Scenes" album. Another song on that album, "Peel Me a Grape," is good for hearing a speaker's resolution. A resolving one will easily reveal the reverb added to the mix, and the little special effects (like the popping of a cork) in the song.