Fender Bassman 400 appreciation thread!

Discussion in 'Amps and Cabs [BG]' started by barroso, Dec 22, 2002.

  1. barroso


    Aug 16, 2000
    I used for some gigs this combo. added a tubeman plus preamp in the rack space and combined the amp with my 4x10 Ampeg cabinet.

    i play in apower trio and we play seventies rock'n roll.

    i was really surpriesed how good the setup worked. great sound with my Precision, rickenbacker and G&L L2000 too.

    i am tyhinking of buying this amp.

    who likes the bassman 400?

  2. finn74


    Nov 28, 2001
    I purchased the fender bassman 400. At 350 watts it's a good amp for small to medium sized gigs. It has a very nice tone to it. This amp is light years away from the Fenders previous line of bass amps. Experienment and compare it to some of the other combos out there and you'll be surprised. It's definitly hundreds less that the Eden Metro, SWR Redhead of Peavey BAM. A word of caution. The amp cannot run any lower than 4ohms and the internal speakers are wired to 4ohms. So if you're thinking about adding a cabinet to it forget about it unless you disconnect the internal speakers.
  3. I thought people could order an upgrade kit to allow an extra cabinet to be added???

    From Harmony Central:

    "As I said earlier, it is stupid that Fender didn't provide the extension speaker jack stock since this amp has the extra power to power another cabinet, but upon getting the kit, it is simply a matter of opening up the amp itself and pulling in the little jack piece provided in the kit. "

    Shouldn't this guy have killed his amp?
  4. top028


    Dec 14, 1999
    Lancaster, PA
    you can add annother cab in parallel. The final impedance would be 4 plus what ever the chosen added cab is. ie. 4+8=12 however if added in series the same two cabs would become 2.7.
    1/4=.25 and 1/8=.125


    I dont know an easier way to show the series equation than the example...

    Now, you could rewire the combo to 8 ohms and then add in series with the ampeg (probably 8 ohms) and get a nice and happy 4 ohms for the amp. Now it would be really ingenius to put a series/paralell switch on the fender...however an accident could be disasterous.

  5. uhm, I think you may have gotten a bit off track. Series Impedances combine. Parallel impedances to which the values are unequal are lower than the lowest resistance in the circuit.


    the bassman 400's internal speakers
    (4 ohm)
    ext cab
    (8 ohm)
    12 ohms

    take the reciprocals of the impedances:
    1/4 + 1/8 = 1/Rt

    it the internal speakers came to be 4 ohms, then the highest likelihood that they are 8 ohm drivers wired in parallel. there is no way to rewire them to be 8 ohms.

    Even if you took a 410 cab that is 8 ohms (generally 32 ohm drivers) and wired them all in series/parallel, the 400's speakers would see the most power due to the lowest impedence. and besides, the most logical schematics would yield either 32 or 3.5555 total ohms. neither one is easy to wire or practical.
  6. top028


    Dec 14, 1999
    Lancaster, PA
    now, I know for sure resistance and capacitance use the equations like you described. I thought that inductors were reversed. Since inductors are coils as far as I know, I figured speaker coils were the same. Unless my worthless school taught me that wrong too. but I found this online to disproove myself.


    OK I figured out my problem....I re-read my old text books. Inductance and Impedance are two WAY different things. I was calculating for inductance.
  7. I figured out the parallel and series equations but I was just curious about the extra cabinet. I agree with finn74 that you can't add another cabinet based on the math but I don't understand the thing regarding the extra speaker extension. When they say speaker extension, they mean adding another cabinet, right?
  8. Munjibunga

    Munjibunga Total Hyper-Elite Member Gold Supporting Member

    May 6, 2000
    San Diego (when not at Groom Lake)
    Independent Contractor to Bass San Diego
    Well, to steer the thread back in the original direction, I've played through a Bassman 400. It did not suck. Actually it sounded kinda good. Coming from me, that's saying something, eh?
  9. Damn.. I don't understand any of impedance related stuff you're all talking about but I was thinking of getting the Bassman 400 combo this year and to add an extension cabinet to it later.. maybe a 1X15 or another 2x10.

    I have very few experience related to seting up amp or combo + cab rigs, but I had faith on doing that.

    So.. Is it impossible to add an extension cab to the bassman 400 combo without muting the 2 10's??