Orange Amps Forum

I have two OR50 40th anniversary custom amps. Only 40 were made in 2008. They should all have a different voicing.

As I could not hear any difference between these two amps I had them opened to see what makes them unique.
I thought this was interesting to share with my fellow "Orange-ists".
The amps have different tonecap values in the preamp, subtile differences are measured in the spectrum.
Preamp topology is the same and this is the reason why a difference between the two amps are hardly audible.
Seems I got two of a kind.

Here are some pics of the amp guts:

Those amps look a work of Art. Very nice.

I see Sally was born on Valentines Day

Damn, quite an expensive comparison project. Even if they were all hand-wired and have different names... they are still the same amp, so I don't think you should expect to have two totally different sounding amps there. If any difference does exist, I'm sure it's hardly noticeable even to the trained ear.

Beautiful. Thanks for posting. Since they are virtually identical, you should "free" one to the market for someone else to enjoy.

dreamdistortion wrote:Beautiful. Thanks for posting. Since they are virtually identical, you should "free" one to the market for someone else to enjoy.

...if it only wasn't so hard to part...

It would be interesting to hear a tone comparison between the 40th Anniversary edition and the current production model OR50.

Interesting. .068 mfd coupling caps in Sally (earlier), and .047 mfd in Angie (later build). I'm assuming those are the later stages and PI due to the higher voltage handling. Maybe he felt the amp needed more clarity. It's tough to see, but it looks like he bumped the bypass caps down from 47 mfd to 22 mfd. Those changes are enough of a difference that you should be able to hear it. Though probably not until the amps are cranked up a bit.

Cathode and plate resistors look to be the same. Topology looks identical, as you said.

Very nice looking build. The only thing I see that's a little sub par is the fact that he floated those bias feed resistors. I'd think it would be safer to throw a single post terminal strip on the octal tube mount to make sure that doesn't move. The chassis is enameled, but still, those floating solders look out of place to me in an amp that is obviously built so well. Nice to see all the shielded wire used as well.

Thanks for the pics!

-Nick

PLEASE sell me one..... please?

My retro 50's plate voltage was 385V too. Here's a pic of the guts to add to the comparison. Those 40th anniversary amps are soooo cool. I wish they weren't like $5k! Haha.