VOGONS


First post, by AppleSauce

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Howdy to anyone that can help , I'm tiring of using the stepdown converter i own for the Japanese supplies that came with the various roland modules I got.

Could anyone reccomend an Australian dc adaptor suitable as a replacement? I'd be okay with a cheap no name as long as it was safe and reliable and someone could vouch for it.

I'd get a roland acb 240 but they tend to be a bit pricey and I have like 4 modules and another on the way. Plus I'd probably need one for the mpu 104 switchbox for the leds. So that's like 6 of em.

Oh and the last module is a Yamaha mu 80 I'm guessing ill need to get a 12v 700ma adaptor for that.

Reply 1 of 9, by Tree Wyrm

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Get a modern Roland PSB power supply, it's 9v 2a, more than enough to power multiple devices through daisy chain. I've got one and it's sufficient to power MT-32, SC-55, MPU-105 switch and M10-MX mixer.

Reply 2 of 9, by imi

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daisychaining power for audio devices is bad practice, ideally you want each device on it's own isolated power supply.

in reality though, it might not have much impact... but then again, it also might.

Reply 3 of 9, by snufkin

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Mind that, if I remember rightly, Roland round power connectors used to have (might still have) centre ground when most other round connectors are centre positive. So you'd probably have to do a little bit of rewiring if using generic adapters.

Reply 4 of 9, by dionb

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Not sure how well it would work with audio, but I have an alternative: my Japan-bought Roland A880 patchbay with big old internal transformer wants 100V. After messing around with an external 230v-100V stepdown, I decided to fix it. Roland had a spare part number for 230V, but of course decades later I couldn't track it down. So I took a look inside at what happens after the transformer, and turns out the PCB runs on +5VDC, and in the case of my A880 uses a lot less than 2A at that voltage. That's USB teritory - so I soldered a USB power cable to the output of the VRM on the logic board, plugged it in to a 2.5A capable USB power adapter - and it works like a dream, a far more efficient low-power dream than it originally was.

Of course my patchbay does MIDI, not audio, so no analog sound quality considerations - but maybe USB power would be worth looking into.

Reply 5 of 9, by AppleSauce

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Im planning on having a multi extension outlet with 6 separate switches for each outlet. I'll only have one device on at any given time. And ill have a switchbox for the audio cables and the midi devices.

So really I just need to know where I can get a buncha aussie compatible cheap dc adaptors that won't blow up.

Basically I just want the convenience of hitting 4 switches (midi switchbox , audio switchbox , extension , device) rather then plugging and unplugging stuff every time.

And yeah hopefully there are centre negative ones I'm sure ebay probably has some cheap ones that work fine right?

Reply 6 of 9, by Tree Wyrm

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imi wrote on 2021-10-28, 10:19:

daisychaining power for audio devices is bad practice, ideally you want each device on it's own isolated power supply.

in reality though, it might not have much impact... but then again, it also might.

Doesn't have impact for me, saves a lot of space too. Ones I listed are all 9v 500mA devices with center negative.
Alternatively there are also power supplies for pedal boards, though cheaper ones might not be properly isolated internally. If mine wasn't already in use I would have done that instead of daisychaining.

Reply 8 of 9, by AppleSauce

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Well I got one of these, hopefully it'll do the trick

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Reply 9 of 9, by CrossBow777

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Because most of my modules didn't include PSUs originally with them, I actually use Genesis/Megradrive PSUs with some of my Roland gear. They are the same center tip negative polarity and at least 1A output. Not a true Roland PSU but they aren't difficult to find and a very good match specwise.

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Midi Modules: MT-32 (OLD), MT-200, MT-300, MT-90S, MT-90U, SD-20