Today, I A/B'ed my newly acquired Marshall 1992LEM head against my main 1973 Super Bass (bone stock). The settings were the same (Lemmy's preferred) for both amps:
Bass - 0
Middle - 10
Treble - 0
Volume I - 8
Volume II - n/a
Both heads were plugged into my JCM 800 Bass Series 4x12 and 2x15 cabs. I used my '76 Rickenbacker 4001 (set to the DiMarzio X2N-B bridge pickup) plugged into the Channel 1 high input. No effects, just the bass straight into the amp. I used my Zoom H4, about 5 feet away and about waist height, to record the clips. Between head changes, I didn't move it or change any settings. No eq'ing or post processing. The song is Ace of Spades (of course
). The first couple of notes are chopped off, because I was playing to the track (using my mp3 player and in-ears), and didn't have a count in.
Some personal observations: Setting the heads the way I did, and using my Rick, copped Lemmy's live tone bang on. The '73 Super Bass head is WAAAY louder than the 1992LEM (this MAY have to do with the fact that the 73 has NOS Mullard xf2 EL-34 power tubes, and is biased to 70%, and the LEM head is running the stock Svetlana EL-34s, and is at the factory bias setting, which I understand is usually pretty cold. Both amps have NOS Mullard ecc83s in the preamp. Another possibility is that the plate voltage on the 73 is higher than the LEM, but I haven't actually measure the LEM yet, so that's pure speculation). When you listen to the tracks, the volume difference is strictly from the different amps. The 73 is SO loud at 8, that it overloaded the H4 mics! Overall, I'm not TOO happy with the quality of these recordings, but they give you an idea of what these amps sound like cranked up, hehehe...
1973 Super Bass: https://soundcloud.com/clammy69-1/1973sb