1979 Orange OR145 Bass Combo Circuit Schematic/Diagram

[Lemos]

Hello Orange Amplification community. I am in search of a 1979 Orange Hustler OR145 Bass Combo circuit schematic/diagram. I have read that it is very close to the Super Bass of '79, in that the SB has four EL34's, while the OR has only two. I have seen pictures of both models, and they do seem to be identical, just not sure on the values. Any assistance will be greatly appreciated. Here is a user verified schematic of a '79 Super Bass: http://www.orangefieldguide.com/OFG_SCH ... erBass.pdf" onclick="window.open(this.href);return false;

Thank you in advance,
Dave

[a.hun]

Hi Lemos, welcome to the forum!

Very rare amp. Literally only a couple of threads on it here, but they may possibly help you some.

Good photos:
http://forum.orangeamps.com/viewtopic.p ... ilit=OR145" onclick="window.open(this.href);return false;

Some circuit details:
http://forum.orangeamps.com/viewtopic.p ... ilit=OR145" onclick="window.open(this.href);return false;

You could always try Orange themselves. Maybe if you are lucky they might still have something for you.


Andy.

[jontheid]

I've already given some info regarding this here:
http://www.vintageamps.com/plexiboard/v ... 1&start=15" onclick="window.open(this.href);return false;

The o/p doesn't have an OR145, he wants to build a replica of one.

This is what an OR145 PCB looks like.






This is exactly the same PCB used in the Superbass, it also has 'BASS' written on it.
It all matches up to the Superbass schematic values to me, I can't do all the resistor values though as some are a bit blurry and my colour vision is poor. If the o/p has good colour vision he can check all the values against the Superbass schematic. If anybody finds any significant differences please let me know.

Gladmarr has got a the guts of a 90s reissue Hustler amp (the guitar version, not the bass) and may be able to give you a good pic of the faceplate to copy. He also may have the dimensions for the cabinet, the bass version will just be a bit taller to accommodate the bass port. The main chassis is the same as the classic OR120s afaik. I've already given the o/p a link to the PCB trace for this amp. It is pretty easy to build on turret board as well I'm sure.

You will be able to get the mains transformer, output transformer and choke from Orange themselves. Mercury Magnetics can supply equivalents also (just use OR120 type iron).

This guy should be able to do a suitable chassis. You could ask for a GT120 type, but without the faceplate:
http://hilbishdesign.bigcartel.com/prod ... eplate-kit" onclick="window.open(this.href);return false;

You'll have to fabricate the brackets that go from the chassis to the angled Hustler-style faceplate though.

Cheers,
Jon

[bclaire]

For the record, there is a Series II bass faceplate on ebay right now....

[Lemos]

Thank you guys for your quick responses!

To a.hun : I have checked with Orange, and they told me they do not have direct access to the files / do not want to relay the wrong information.

jontheid : Thank you for providing that information- I am going to give it a little while to see how many people agree/disagree with the similarities before ordering all the components.

bclaire : I am going to have to decline on the eBay faceplate, as I will be custom building the cabinet out of a wooden log. (Custom wooden knobs, hemp speaker grille, etc.)

As regards to that: Would anyone happen to know how to coat the interior to prevent overheating, burnouts, and/or fires? I have some nice, clear shellac that I will most likely be coating the exterior with- depending on how much I have left after this other project I am working on.

[Lemos]

jontheid, I see you posted over in the VintageAmps forums, stating one is a 120w head, while the other one is a 60w combo. I am wondering- how is one 60w, and one 120w, while both using the same circuitry, and would the 120w not create too much power / 60w create too little power?

-Dave

[jontheid]

One has 4 x EL34 output tubes (Superbass) , the other only has 2 x EL34 output tubes (OR145).

If you take the Superbass schematic and get rid of R32, R33, V4A, V5A, R37, R38 then you have the schematic for the OR145. This removes the grid stoppers and screen resistors for two output tubes, and the tubes themselves.

Please note: none of these components are on the PCB, so the PCBs will still be identical.

Have you got any previous amp building experience?
Have you worked with tube amps before?
Building an OR145 clone isn't going to be the easiest of things to do for a first-time builder.
Is there any reason why you are so fond of the OR145?

Cheers,
Jon

[Lemos]

I built a radio in high school a few years back, unsure if it ever ended up working. The OR145 just rings a bell in the amplifier world to me. I am hoping it should not be too difficult, as I do understand schematics, and their visual-to-physical formatting- but no, I have yet to work with my first tube amplifier. My original plan was to custom design the entire circuit, but I would probably end up mimicking some $25 practice amp, as my diagram design skills are not too advanced. My second plan was to take apart one of my amplifiers that I have previously purchased and swapped out the components in those, just to get a rough idea of how everything was working together- although I probably would have walked away with more of a different tone, rather than a wider range of knowledge. I do not know, it is going to be sort of a hit and miss plan at this point with the home fabricated OR145, just a lot of building, following some testing and troubleshooting. I am sure I will eventually hit the nail on the head.

[Randy Bass]

I'd start out with a basic Fender Champ kit or something before attempting a build of this magnitude. A rare PCB-based amp with scarce online documentation / resources is probably one of the worst possible choices for a first-time handwired DIY build.

[Lemos]

None but the minority of the dinosaurs we know today triumphed between a wingspan of tissue, carefully wrapping the very material to allow flight in their spirits. The majority of them caressed the earthen grounds with claws, nails, and flesh. Do you think not this said flesh carried jealousy within their hearts, when roaming the planet's crust? It hath due that this crust rise, and become one with the unknown lives of wind. Between their souls, a connection lost in language we seem not to seek this current hour. Before the crust rises, we must yank it's chains from above, we must fight for altitude in our journeys and chosen paths. I ask this of you now: seek this language, before the hour vanishes beneath the pressure of this grand equation.

[Gladmarr]

This seems like a good time to mention that tube amps can KILL YOU with the high voltages inside.

Not only that, but it will hurt the whole time you're dying.

[bclaire]

None but the minority of the dinosaurs we know today triumphed between a wingspan of tissue, carefully wrapping the very material to allow flight in their spirits. The majority of them caressed the earthen grounds with claws, nails, and flesh. Do you think not this said flesh carried jealousy within their hearts, when roaming the planet's crust? It hath due that this crust rise, and become one with the unknown lives of wind. Between their souls, a connection lost in language we seem not to seek this current hour. Before the crust rises, we must yank it's chains from above, we must fight for altitude in our journeys and chosen paths. I ask this of you now: seek this language, before the hour vanishes beneath the pressure of this grand equation.

WTF?

[a.hun]

WTF?

Yeah, the last post from Gladmarr made considerably more sense to me!

Maybe Lemos is a free thinking birdie and we are all dinosaurs doomed only to dream of flying? Yeah right, there are more ways than one to become extinct!

Andy.

[Hubaxe]

These Shellac varnish vapors are really strong..

[Lemos]

Doomed to the earthen crust my comrades.