About to buy an 1972 Orange OR120 Pics only

[Kralmestrand]

Hi!

Like the thread says I am about to buy a full stack Orange OR120 from 1972 (cabs are from 1973 and 1975) and just wanted to ask if people with knowledge of them could look at the pictures provided and give me any info about it.

I figured I'd get it and let a tech look at it before I even use it to get it in tip top shape.

I am quite new with tube amps, only having owned a TH30 for about a year. I have no idea if anything looks good or not, or if the tubes are in great shape or not.

I hope these pictures will provide some insight

[Jondog]

Looks to be in good shape too! Have fun!

[Gladmarr]

The choke looks funny. Not sure why. It's had the big caps replaced. Other than that, it needs to be flipped over so we can see the guts.

[bclaire]

Smart plan having a tech check it out first... maybe retube just so you know what you're dealing with from square one.

[Kralmestrand]

The choke looks funny. Not sure why. It's had the big caps replaced. Other than that, it needs to be flipped over so we can see the guts.

I finally got a picture of the insides of the amp. Crossing my fingers that it's in playable condition!

[Les Paul Lover]

Some of the caps and one pot have been replaced, which isn't a bad thing, just something to be aware of when discussing the price. Only mentioning this because some people try to charge a higher price for all original amp. On 40yo amp, these caps replacement are to be expected.

Looks like a great amp by the way.

[Jondog]

Looks good to me. replaced parts don't bother me as long as they are the proper parts and done correctly. It's a sign of good up keep. I'd say it's in good shape. Not lots of chipped flaky rusted paint, no broken knobs or out of place mods.

[Gladmarr]

Yeah, that looks healthy. That's pretty clean inside for a pix-only. And it has the mid-lift inductor - a relatively rare option.

[OR73]

Is it just me or are there a TON of wires running to and from the trannies? I'm no amp builder (amplification retardation is more likely) but from all the gut shots I've seen there are usually only 3 or 4 wires per transformer. it looks...well, odd.

[Gladmarr]

Pretty normal for a pix-only OR120. Here's a similar shot of mine:

[davebolden44]

8 rectifier diodes? I would love to better understand the engineering of these ancient masterpieces

[Gladmarr]

Yeah, the earlier Oranges all had 8 rectifier diodes. It was a standard full wave bridge, just with two diodes per side instead of the usual 1.

My mid 70s OD120 has 8.

[davebolden44]

neat but does it really make a difference?

[Gladmarr]

No idea. I'm guessing it's for current handling, but I've never really put any thought (or math) to it. It would certainly double the diode drop through the bridge.

[Kralmestrand]

Hi!

So I finally bought it and woow, it looks amazing. I still haven't been able to try it (just checked that it worked and brought it home).



Here it is. Sorry for the quality, it was a bit dark so I brightened the picture which whacked it up a bit.

A question again:

I totally thought the old cabs were the same as the new ones (V30 speakers, rated at 60 watt each for a total of 240W), but it is not, and each cab is rated at 120W.

Does this mean that I actually need both of them to not blow anything up when cranking the amp to full?

I've read that the cab wattage need to be double that of the amp, but I don't know why or even if it's true. To me it would seem logical that I need a 120W cab for a 120W amp but it might not be that simple.

Hope to get some answers, because if I need both, then saving for a brand new PPC412 will commence immediately..

Or I guess I could use a THD Hotplate (16Ohm) on the single cab and reduce it with -4dB which would put the rating from the amp at about 50W.