Oddball question for the other electronics geeks

[Old Guy]

first question...anybody do Hammond organs?

I'm being offered a power amp section from an H-100 series...first thing I did was chase a schematic.

It has 3 amps. Left, right and bass.

So my brain starts cooking up ideas about adding a crossover section...to have left, right and sub for a stereo system. L/R amps are 2 P/P 6BQ5 so should be about 15/side....plenty for an old guy...

Good idea/bad idea whatcha think?

[skeggordon]

Could work out fine, would need to make sure that your speakers matched the output impedance of the amplifiers, don't know what the Hammond speaker's impedance is. The amps may need a high input level as well, something else to check.

Should be fun anyway!

Jay Gordon

[bfish]

Although I have an H100 in my stable of Hammonds, I don't recall the amp topology offhand. As Jay mentioned, they do have a rather high input signal requirement, and most are balanced in as well. The other Hammond biamps I've "done" (from tonecabs) have a first order XO around 200Hz, with an extra channel for the reverb tank. While in general they do very well on the low end, I'm unsure of the HF response, as they only needed to go so far.

If you just want the amp, I've got at least two "spares". PM if so. From memory, I think the tonecab biamps (HR40 etc) would be more conducive to hifi. Have a few of them too. 6V6 PP beats 6BQ5 in my book, but they're beefy monos, so make some room...

The H100 was an initial venture into hybrid SS.\

Added;
Since the H100 was all internal, it should accommodate low level inputs OK, unlike the tonecab amps that were fed by a balanced pre from a B2/B3/C2/C3.

[Old Guy]

Thanks guys.

BTW Brad were you ever able to get the Altec mics working? Just curious, with my eyesight I wasn't about to tear them apart.

[bfish]

You're welcome.

It came back to me today why the two H100 spare amps I have remain untouched. They each use 3 7199s... at ~$50 a pop... There are workarounds of course, but that was enough for me to shelve them.

As to scrapping out an H100, there are almost no parts that are interchangeable with the "desirable" A/B/C/M models, so no recovery on investment there. To be fair, an H100 is a pretty cool player when everything works, but they're such an oddball that getting all those early SS devices to work is a real chore.

Haven't done more than eyeball the mics, my LR is still in "winter mode". When I move a piano and some other junk back in front of the fireplace for summer, I can reclaim my desk/workbench. That never happened all last year though, so this year's shuffle (or should I say shovel?) will be a chore. All you guys with SAF/GAF/WAF to contend with should be thankful. At some point, she probably saw a real mancave/boars nest like mine and vowed to never let that happen in her domain...