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Old 23rd April 2013, 04:47 AM   #531
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I'm having a bit of a weird issue with the Buffalo 3 / Legato 3.1 and the Kevin Gilmore Dynamid (Balanced Dynalo) - I get no sound except when I'm powering down the amp. I'm assuming this design requires the use of output caps and some protection circuit is kicking in, but I'm really unsure. The unbalanced outputs of the Legato work perfectly with a small amp I use for testing.

Any ideas?

NOTICE: Looking at the schematic of the Dynamid amp, it's running in bridge mode where Input and Ground are separated only by a resistor and all 4 channels operate independently, so it might really by an off-case scenario that it doesn't play well with Ground/Signal DC.

Last edited by FallenAngel; 23rd April 2013 at 05:14 AM.
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Old 23rd April 2013, 05:28 AM   #532
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RESOLUTION: Just wired in output caps and it works like a charm.
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Old 25th March 2014, 08:02 AM   #533
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My Legato 1.0.3 is not working any more and I am trying to do a bit of fault finding. The switch relay appears to earth the output of the opamp when there is no +-12V supply present. Could somebody explain the function of this and why it is desirable to do this?
I presume that if the relay/switch was removed, the Legato would function normally? What are the downsides to removing the relay/switch?
Many thanks in advance for the help
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Old 25th March 2014, 02:32 PM   #534
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The relay prevents thump at power on/off.
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Old 25th March 2014, 03:01 PM   #535
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Thanks Russ. Will remove it and see if I can get the Legato working again.
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Old 25th March 2014, 10:31 PM   #536
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Yep Legato is working fine with the switch/relay removed. Anybody know a reasonably priced source for one of these (Omron G6K-2P-DC24) as the total cost of getting it from RS here in the UK is a ridiculous 25?
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Old 25th March 2014, 10:50 PM   #537
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Quote:
Originally Posted by themystical View Post
Yep Legato is working fine with the switch/relay removed. Anybody know a reasonably priced source for one of these (Omron G6K-2P-DC24) as the total cost of getting it from RS here in the UK is a ridiculous 25?
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Old 4th April 2014, 12:26 PM   #538
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Now sorted, thanks very much to Brian.
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Old 18th May 2014, 02:21 PM   #539
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What's the output impedance for SE output?
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Old 24th May 2014, 07:24 PM   #540
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Could someone please help me to make sure i'm doing it right:
i recently built Buffalo III with Legato 3.1 and while configuring Placid HD was quck and i ended with something like 520mA with 50ma being shunted, but my Legato only eats 230mA per side at -13/13V input. Isn't it kinda low? From manual i know it supposed to eat 350mA, but if i set BP to that i get 200mA+ shunted and heatsinks get pretty hot...

It does play music for 2 days now and all seem to be normal, although i have a feeling it's a bit "soft" atm and could use a bit more dynamics\attack\drive (compared to previous dac i had). I'll be getting bigger trafo soon (i have only 30VA atm) as some people suggested and maybe increase voltages to 15V on Placid BP once i'm sure about temperatures...
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