New old amp. Vintage German madness

Stuckfast

I saw this going quite cheaply in an auction and couldn't resist. 



It's a Hohner Orgaphon amp from, I guess, the mid Sixties. In typical German fashion it's incredibly over-engineered compared with British or American amps of the time. Big and heavy but from memory not as heavy as an AC30.

The preamp and reverb are mounted in the top part of the amp, the power amp and power transfomer are at the base of the cab. There are five separate input channels! The first four have duplicate inputs on jack sockets and DIN sockets:



Looks like there's a sixth input on the lower board that goes straight to the power amp. Bizarre external speaker connection options -- they're switchable for 16Ω or 4Ω but not 8Ω, and use what looks like an old hi-fi connector. Love the on/off button.

The power amp tubes are, I believe, PL84s, which was a type commonly used in TVs. I guess they used the same chassis for another model with four of them. Anyone recognise the speakers?



It has spring reverb and tremolo, with separate footswitch inputs. The architecture is more like a mixer than a conventional amp. There's a master reverb level control and each channel has its own reverb send, which I think is pre-gain, so if you turn the channel gain all the way down and the send all the way up, you just get reverb.

The five channels all have different controls and presumably different purposes. Tremolo is only on channels one and two and is activated by pulling up the gain pot. Channel two seems to be a low-impedance input as it sounds very quiet and dark with guitar. Channel four just has a gain knob, and there are no controls on the 'tape' input which is channel five. 



I've fired it up briefly at home and it's an interesting amp for sure. It seems a bit noisy so could possibly do with a service. The tone controls on channel one interact in a strange way, it's quite hard to find the sweet spot but there are some good sounds to be had. Channel three is probably the best sounding for guitar. It will distort if you turn the gain all the way up but was obviously designed as a clean amp. Tremolo is great and the reverb seems pretty good. 

I'll drag it to the studio later this week and spend a bit more time with it.

Winny_Pooh

Very cool looking. You could probably mod one channel to make it hotter, cascade 12ax7s etc

BillDL

It looks remarkably clean for its age and has obviously had a replacement handle.  What's the date on the PAT sticker?

Did they have IEC C13/14 connectors back then?  I know the standard was published in 1970, but did the connectors already exist?  The speaker frames look as though they have been refurbished they are so clean.

A quick google reveals that there is a lot of information out there about these amps in the 41MH and 45MH models especially, and there are also schematics available and YouTube videos featuring them.

p90fool

The IEC socket looks like a mod, and there's some dangerous looking exposed areas around it and the voltage selector!

Stuckfast

The IEC socket is definitely a later mod. PAT stickers say 2019. 

I removed the rear baffle to take the internal photos -- with it in place there wouldn't be any way to touch anything internal whilst it was powered on.

Stuckfast

I am alone in the house this morning so I tried cranking it up. Turns out you can get some very fine overdriven sounds on channel three. Channel one is still a mystery, it has a bit less gain than channel three and the tone controls seem very extreme. If you engage the tremolo you get an overall level drop and it won't overdrive so easily, which is a shame. Reverb is very nice though.

Still wondering about the speakers. The bass sounds quite tight, but they're obviously putting out some sort of super low frequency thump on low notes -- you can see the grille cloth being blown in and out. Not an amp you'd want to put a ribbon mic in front of.

57Deluxe

...anything that promises to make your organ bigger...

roberty

That's really cool. I wonder if some of the channels are voiced for electric organs maybe. The quiet channel might prefer a line level signal

Stuckfast

I think probably channel two is intended for line level signals. Wondering if channel one might be intended for accordions or something like that? It's pretty weird, you need to turn the bass right up to get any low end from a guitar, but then the treble control also affects the low end in some way.

Anyway I think these are probably the last 'vintage' amps that are still affordable. If it said Selmer or Ampeg on the front you'd be paying a lot more.

ICBM

The signal levels in mV marked on the channel inputs may help identify what they're for. Accordion, keyboard, guitar and mic are all possibilities. What's bizarre is that the tape recorder connection - the only one that could really benefit from a DIN socket - is the only one that doesn't!

The speakers are probably made by whoever were the German equivalent of Wharfedale or similar.

Wazmeister

I've got to say, that looks propa cool !

cathodyne

Congratulations on the auction win.  That looks fun!

Kittyfrisk

Very cool looking amp, nice find. Sounds like it was named by a Barbarella fan 
Ignore the PAT sticker, they have been widely available since the 1990's & being filled in by hand, prove nothing.

Stuckfast

ICBM said:

The signal levels in mV marked on the channel inputs may help identify what they're for. Accordion, keyboard, guitar and mic are all possibilities. What's bizarre is that the tape recorder connection - the only one that could really benefit from a DIN socket - is the only one that doesn't!

The speakers are probably made by whoever were the German equivalent of Wharfedale or similar.

Yes I thought the same about the signal levels, but it's a bit hard to tell. Pretty sure channel two is a low-impedance input, probably intended for line level signals. Channel one seems to expect a slightly lower level than channel three, but in practice channel three is a bit louder with guitar. One and three both have treble and bass tone controls, but they seem to act differently in each case.