Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Buris on September 11, 2016, 03:41:26 am

Title: transformers for orange AD200B?
Post by: Buris on September 11, 2016, 03:41:26 am

Hi

I'm planning on building a Orange AD200B inspired 200w bass amp using these schematics of the mrk III:

http://s853.photobucket.com/user/bernardduur/media/Amps/Orange/AD200BMarkIIIPSU.jpg.html (http://s853.photobucket.com/user/bernardduur/media/Amps/Orange/AD200BMarkIIIPSU.jpg.html)

i'm kinda asking the same question as this threat but i am going for the full 200 w amp!

http://el34world.com/Forum/index.php?topic=19816.0 (http://el34world.com/Forum/index.php?topic=19816.0)

so my question is where to buy transformers for this amp? i know of the MM transformers but they are just too expensive! It must be possible to get a set of spare part transformers or something for this amp but where?

i hope you can help me!

Thomas

Title: Re: transformers for orange AD200B?
Post by: kagliostro on September 11, 2016, 06:12:43 am

I know nothing about the Orange AD200B (B+ voltage - Power Tubes - Original OT impedance)

said this

Have you give a look to Weber transformers ? Some time ago they had an AB200 Kit, a big power amp

Franco

Title: Re: transformers for orange AD200B?
Post by: PRR on September 11, 2016, 11:43:11 am

https://www.talkbass.com/threads/orange-ad200b-replacing-stock-ot-with-mercury-magnetics-oro-200-m.898436/ (https://www.talkbass.com/threads/orange-ad200b-replacing-stock-ot-with-mercury-magnetics-oro-200-m.898436/)

$300-$400 for a 200W OT or PT does not sound expensive to me.

The whole amp retails for $2,000.

You can rarely scratch-build an amp, ALL parts considered, for less than a factory price. Their quantity discount covers their paid labor. (Different when you have a huge junk-pile, but nobody has 200W parts laying around.)

200W tube amps are RARE. I have only seen a couple single-channel amps that size. (And I did gig with three 2X150W tube amps, well over 700W on tap.)

Most tube amps over 80W are real-clean. The total demand for such parts must be tiny. Cost is a lot to do with volume. Factory gets into a 1,000-part routine, costs come down. Arguably big-tube-amp work can be done with compact economical boxes from the Rock/PA supply store.

That schematic can't be complete. It only shows 2 power tubes? No OT impedance spec? No voltages noted?

And be real. What can you do with a 200W amp that you can't do with a 100W amp? Or a 50W micced into a 2,000W PA system?

You could consider buying two sets of "100W" PT and OT from Fender/Marshall replacement parts. But I don't have a clue if the Orange circuit could be transposed to the voltage/impedance zone.