SOLD Demeter VTBP-M-800D 800w hybrid amp with Jensen Transformer and Mono carry bag

Discussion in 'For Sale: Amps, Preamps, and Cabinets' started by eddiebo, Sep 15, 2020.

  1. eddiebo

    eddiebo Supporting Member

    Nov 13, 2002
    Montclair, NJ
    New Jersey
    United States
    01_VTBPM800D.jpg 02_VTBPM800D.jpg 03_VTBPM800D.jpg

    Pristine condition without a flaw anywhere, from smoke and pet free environment. Mono carry bag and two 1/4" to Speakon speaker cables included in the sale.

    Price includes UPS or FedEx GROUND shipping in the CONUS ONLY or will reduce by $50 for local pickup @ NJ 07013.


    PayPal or Venmo payment accepted
    PM with questions

    SPECS below.


    Demeter VTBP-M-800D Amp with Jensen Transformer

    In 1982 James Demeter built the first of his series of VTBP-201 pre-amps. His idea was to build a Tube Audiophile Pre-amp with Classic Bass Amp style tone section. There were other Pre-amps at the time but they were just guitar amp circuits that had major design flaws. His first customer was Leland Sklar. Lee took our proto-type to try it out and kept it. Lee used the pre-amp and it’s backup for another 25 years until he downsized his rig. In 2012 He decided to donate the #1 Pre-amp back to its creator. We were very happy to see it back and of course we had to listen to it. We were amazed how warm and clear it was. It sounded very similar to the current VTBP-201 but it was rounder and a bit slower than the newest model due it unregulated power supply and old school parts. Around the same time we found 150 of the original PCB’s that were used in that model. We decided to clone Lee’s pre-amp but, put it in the smallest box possible with our 800D power-amp. The result is the VTBP-M-800D. At 10.5 lbs. It is one 800 Watt tube tone monster.

    All tube pre-amp circuitry Hand wired in the USA using High quality components, DC filament, full 280V high voltage supply. Classic passive tube tone controls Treble, Middle, Bass with frequency selector and presence with frequency selection. We replaced the original bright switch with our new Mode switch that lets you control the overall tone: Dark, Normal and Bright. The unit has a pre-amp output if you need to run more amplifiers. A select Jensen transformer drives our 800 watt class D Amplifier. There are two Speakon combo jacks on the back to hook up your speakers. We offer upgrades for Jensen transformer Direct outputs and a line level effects loop. The amp weighs 10.5 lbs and messures 13”wide x 5.5”high x 9”deep. Built right here in the USA in our Barn in Templeton CA.

    Tone section:
    Treble Control: The treble control gives 6 dB of boost or cut at 4 kHz (6dB per octave, shelving type).
    Middle Control: The middle give 6dB of boost or cut at 500Hz (wide Q, peaking type).Bass Control: The bass control gives 9dB of boost or cut at a selectable frequency of 60Hz or 120Hz (6dB per octave, shelving type).
    Presence Control: The presence control gives up to 12dB of boost at a selectable frequency of 2kHz or 4kHz (active type, 6dB per octave).
    Mode switch: Dark, is a high frequency cut fatting up your fundmental. Normal, flat opertion showing off more overtones. Bright, brings out the overtones on the dullest basses or speakers.
    Internal Volume Trimmer: This control is designed to match the output volume of the VTBP-M-800D with the sensitivity of any Bass.
    Optional, Studio Output: The VTBP-M-800Dm- features a mic level Jensen DB-E output transformer for a balanced studio output.
    Effects Loop: in/out line level
    Power Amp Outputs: Operating at 4 (800w),8 (500w) or 16 ohm (250w). 1/4” & Speakon
    Preamp Specifications
    Inputs: one instrument level 1/4” jack.
    Output impedance (line): > 1 kohm, (unbalanced)
    Minimum load impedance: 10K
    Input impedance: > 1megohm
    Maximum output: + 24dBV
    EQ gain : + or - 12 dB
    Signal to noise ratio: - 80dB
    THD : .5%
    Outputs (preamp): 1/4” unbalanced , Optional 3 pin XLR Direct out
    Frequency response : 10Hz to 40kHz
    Tube: 1-12AX7a selected 1-12AT7
    Operating voltage: 115V or 230V AC
    Power supply: 280V DC
    Filament: 6.3 V DC
    Power Amp Specifications
    Outputs (power amp): 1/4” Speaker & Speakon
    Output impedance (power amp): 4 ohm, 8 ohm, 16 ohm
    Output Power (power amp): 800 watt RMS @ 4 ohms, 400 watt RMS @ 8 ohms
    CTC564, Matt R, tony caskey and 6 others like this.
  2. 31HZ

    31HZ Supporting Member

    These are great amps, and I would absolutely agree with the "warm and clear" assessment.
    tony caskey and eddiebo like this.
  3. brianrost

    brianrost Gold Supporting Member

    Apr 26, 2000
    Boston, Taxachusetts
    I've been using one at rehearsal (belongs to the guitarist's son) and this is a killer amp, well worth the price. GLWTS.
    eddiebo likes this.
  4. JKos

    JKos Supporting Member

    Oct 26, 2010
    Torrance, CA
    @eddiebo ,
    Wow! That's got to sound good!

    Just to be clear, this one does or does not have the optional Jensen transformer-based mic output (making it a VTBP-M-800Dm)?
    eddiebo likes this.
  5. bucephylus

    bucephylus Supporting Member

    Aug 18, 2002
    Nice amp. I thought all the Jensen outputs were mic level? I’ve never heard of a line level Jensen output on any Demeter amp. Mine are all mic level; and I’ve always assumed that was typical. What have I been missing? Thanks.
    eddiebo likes this.
  6. eddiebo

    eddiebo Supporting Member

    Nov 13, 2002
    Montclair, NJ
    The documentation on the site and in my FS post includes the following:
    • Optional, Studio Output: The VTBP-M-800Dm- features a mic level Jensen DB-E output transformer for a balanced studio output.
    So, if you elect to include the Jensen as in this example, you are correct that the amp model is a VTBP-M-800Dm and the output transformer is mic level as per the spec above.
    bucephylus and JKos like this.
  7. diglo

    diglo Supporting Member

    May 21, 2007
    Get up! Get Get Get Down!
    Great amp. I've owned and sold multiple times. I currently have one and had for sale, but once I plug into it, the sale bug goes away. GLWTS
    tony caskey, bucephylus and eddiebo like this.
  8. eddiebo

    eddiebo Supporting Member

    Nov 13, 2002
    Montclair, NJ
    Thanks, I hear you. I have two nice heads up for sale so its kind of a "whichever goes first" situation at the moment, if one sells the other will get pulled.
  9. BSR6P-Bob

    BSR6P-Bob Supporting Member

    Apr 5, 2005
    Looks like a wonderful amp.
    What is the fan noise like on this one?
    eddiebo likes this.
  10. eddiebo

    eddiebo Supporting Member

    Nov 13, 2002
    Montclair, NJ
    There isn't any at all as far as I can tell
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