HK A500 question

[slowpat]

Hi - I just bought my first tube amp - the Harman Kardon A500 integrated. I don't have the manual, so not sure if it's capable to be used as pre-amp only and/or amp only. There's a "Tape Amp" output besides Tape Out, and I was wondering what that was. And will I be able to feed the signal from another pre-amp just to use the amp section? I have a pair of Klipsch CF-3 and wanted to bi-amp the horns with a tube amp. Thanks.

 

[Bob]

you can do both. Tape out lets you use it as a preamp. Tape in
allows use as a power amp.

 

[cademan]

Actually 'TAPE AMP' is just another line level input. TAPE OUT is just a line level output and is not controlled by the volume and tone controls. Unless it has PRE OUT/MAIN IN jacks, it cannot be used as a seperate power amp or pre-amp.

If you had a schematic, you could wire it as such knowing where to tap into the circuit to seperate the amps input from the pre-amplifier's output.

Unless you can post a picture of the back side, I'm assuming the 'TAPE AMP' is an input as my PAT 4 pre-amp has a pair of jacks that say 'TAPE AMP' which are actually designated as inputs.

 

[slowpat]

I'll try to post a pix later, but I suspect cademan's right on the mark. This is an older HK, and no pre-amp out/main-in during that vintage (same w/ my McIntosh MA5100). I do have the schematics for the A500, but may end up just using it as integrated.

 

[Bob]

I had one of these years ago. There's a tape out for use as a preamp, and there's a tape monitor for use as a power amp. I used a CD player as a source for this puppy through AUX as I recall.

good luck - its a tough unit to get correct.

 

[WopOnTour]

I'm fairly familiar with the H/K Award Series integrated amps, as I have repaired/restored and owned numerous models (one of my favorites being the 7355 powered A500 actually) and AFAIK the various tape inputs/outputs function as follows:

The "Tape HD" input -which I believe stands for HeaD (aka Tape-LO) is meant to connect directly to the to the tape play-back head's low level output permitting a connection for the signal to pass through the A500's 12AX7 preamp tubes V1 & V2 (Channels A & B) while providing a standard NARTB tape equalization scheme via a pair of semi-integrated component plates (the square yellow/brown/red things with multiple wires that you can see behind the controls faceplate) A similar path is also used for the Phono inputs (although the passive component values used within the plate pathways will be slightly different for RIAA phono equalization)

"Tape AMPL" is actually an input designed for the tape output of tape recorder/players that have a built-in preamp that typically already includes it's own tape equalization scheme (e.g. NAB, NARTB, IEC) So on the vintage H/K integrated tube powered amps and receivers (and many others) this input is essentially identical to the "Tuner" and "Aux" inputs and will be hard-wired directly to V3 via the loudness/volume pot slider.

The input signal chosen by the input selector swtch is sent out to the "Tape Out" jack at all times but the signal sent on to the volume and tone controls will depend on the position of the "Tape Monitor" switch. In the OUT position (aka SRC) you will be "monitoring" (i.e. listening to) the source signal from the selected primary input RCAs. However when switched IN, you will be hearing whatever was connected to the "Tape Monitor" jacks.The intention here was to permit you to monitor the output signal from a 3rd head of the tape recorder (if equipped with a monitoring head) in real-time. While NOT technically a "power amp" input (the volume/tone/filter/balance controls and AF stage amplification will NOT be bypassed and still be effective) the "Tape Monitor" input could potentially be used as an additional AUX input with an input sensitivity requirement that will pretty much be at the same level as the other AUX inputs.

Good luck with the restoration of the A500, which BTW I found once properly restored has very decent SQ and makes an excellent headphone amp with the right set of cans...
Regards
WopOnTour

 

[slowpat]

Thanks WopOnTour - great detailed information. Your Citation II in your avatar looks real good by the way.