I would recommend drilling all the way through the heatsink and using an intermediate tap, way less chance of breaking a tap. If you break that sucker in the heatskink you will not get it out easily.
I use Sutton Venom tapping fluid.
.
Hi Tom,
I just bought a SMPS-86 to power a pair of Modulus-86. Some questions about the documentation I received:
Thank you so much
I just bought a SMPS-86 to power a pair of Modulus-86. Some questions about the documentation I received:
- On the SPMS I read "The SMPS-86 uses a Molex MegaFit connector for the power output connection. The Bill of Materials includes three pre-crimped wires for this connector". Since this is supposed (able) to power two amps, shouldn't it be 6 cables?
- Also, Modulus-86 don't have any Molex power connector, so I guess I should either a) solder it but not use it, b) not even needed (pads unprotected sounds a no go), c) solder and use Molex cable but just on the SMPS end (cut the other end and plug through terminal connector on the amps). Maybe even a better, fourth option?
- Last (for now) but not least, surprised to see only black cables are pre-crimped for the Molex connector (at least what I saw in Mouser). Am I missing anything?
Thank you so much
Amps are really coming along, these are going to take RCA inputs and use a single speakon cable to each of a pair of LXmini's which I'm building simultaneously. Massive thanks to Gianluca and the folks over at modushop for doing such an amazing job with the chassis work, the handles have a couple dings but I can keep those facing down. Accidentally mounted the power-86 without checking it would clear the IEC inlet, so will have to re-locate and redrill those holes. Next up will be wiring and testing the amplifiers!
In your case, yes. The. SMPS-86 can be used to power many things. Many have used it to power preamps, for example. Many use the terminal blocks, hence, won't need the Molex connector.
If you don't want the Molex MegaFit, just don't populate it. Save the cost of the connector! You don't have to worry about protecting the pads (I'm not sure where that concern comes from).
Mouser only stock black MegaFit cables. I think those are the only ones stocked by Molex as well. I'm pretty sure you can order custom cables from Molex in whatever colour you'd like. I'm also sure that you need to purchase a minimum quantity (which is probably in the thousands).
You could just colour the ends of the wire with heat shrink or electrical tape.
Tom
Nice setup!!
+1 on the awesomeness of Gianluca & ModuShop. If the dings in the handles bother you, just contact ModuShop. To date, I've only had one goof by ModuShop. An almost symmetrical panel was inserted incorrectly into the milling machine, hence machined 180º rotated. Easy mistake to make. I tossed Gianluca an email and two days later new panels arrived by FedEx overnight. His quick corrective action made it possible for me to demo my Modulus-686 at BAF last year.
Mistakes happen. How you recover from a mistake is what sets apart the mediocre from the great.
Tom
thank you for the answers.
i actually like the molex connector, it's much tidier. i think i'll go for option c, skipping the terminal connectors on the smps instead, and cut the end of the cables then connecting to the amp terminals.
Tom and Adam, thank you for your kind words! Customer satisfaction is always very important for us 
Adam that front panel really rocks! I really like the final result. We have produced an extra one, do you mind if I bring it with me to BAF so I can show it to other people there?
Feel free to contact me about the handles as well
Adam that front panel really rocks! I really like the final result. We have produced an extra one, do you mind if I bring it with me to BAF so I can show it to other people there?
Feel free to contact me about the handles as well
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Here are some more pictures, almost done with the power supply wiring on both amps, just waiting on some mogami 2549 for the RCA's and some speaker cable for the output. I'm thinking of routing the input/output from the amplifiers that aren't close to their respective jack (e.g. one amp's input is far away from the RCA, one amp's output is far away from the speakon) above and below the IEC inlet, I figure it's well shielded so should have minimal EMI, plus my cables are shielded.
Amp 1:
Amp 1 -- Power wiring done:
Amp 2: In progress:
Some notes from along the way -- Heatshrinking the IEC socket terminals can be a bit of a pain in the butt with the relatively rigid wires coming from the transformer, make sure you line everything up perfectly before you solder.
Tightening the bottom plate too much tries to bend the heatsinks out, tighten this plate after lining the back and front panels up to keep the heatsinks parallel.
The holes in the baseplate are pretty sharp around the edges, I've seen other people drill them out and grommet them but I just decided to coat the wire in heat shrink where it goes through the holes to give it extra protection.
Amp 1:
Amp 1 -- Power wiring done:
Amp 2: In progress:
Some notes from along the way -- Heatshrinking the IEC socket terminals can be a bit of a pain in the butt with the relatively rigid wires coming from the transformer, make sure you line everything up perfectly before you solder.
Tightening the bottom plate too much tries to bend the heatsinks out, tighten this plate after lining the back and front panels up to keep the heatsinks parallel.
The holes in the baseplate are pretty sharp around the edges, I've seen other people drill them out and grommet them but I just decided to coat the wire in heat shrink where it goes through the holes to give it extra protection.
Tom,
I got DAC with transformer output. I can do balacned(XLR) or do summing on output transfomer and do RCA output.
I also want to put volume inside the dac.
Then I want to connect it to modulus-86 amp.
Now,
I have two options:
1. DAC with balanced transformer output + balanced volume control -> XLR/XLR cable to -> modulus 86
I want to use something like this
ALPS 4 Channels Volume Potentiometer 10K 50K 100K LOG 6mm Shaft Hifi Audio DIY | eBay
2. DAC with summing done on transformer level on dac output + stereo volume control -> RCA/XLR pseudodifferential cable to -> modulus 86
Which option is better in your opinion?
I just affraid that in case of option 1, variation in resistance in balanced volume control will impact CMRR.
Thanks,
I got DAC with transformer output. I can do balacned(XLR) or do summing on output transfomer and do RCA output.
I also want to put volume inside the dac.
Then I want to connect it to modulus-86 amp.
Now,
I have two options:
1. DAC with balanced transformer output + balanced volume control -> XLR/XLR cable to -> modulus 86
I want to use something like this
ALPS 4 Channels Volume Potentiometer 10K 50K 100K LOG 6mm Shaft Hifi Audio DIY | eBay
2. DAC with summing done on transformer level on dac output + stereo volume control -> RCA/XLR pseudodifferential cable to -> modulus 86
Which option is better in your opinion?
I just affraid that in case of option 1, variation in resistance in balanced volume control will impact CMRR.
Thanks,
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Several of us using this.
BPPBP - Bruno Putzey's Purist Balanced Preamp (well a balanced volume control really)
Between DAC with balanced transformer output and Tom's amps, with good results.
Mine uses a cheap car stereo volume control.
BPPBP - Bruno Putzey's Purist Balanced Preamp (well a balanced volume control really)
Between DAC with balanced transformer output and Tom's amps, with good results.
Mine uses a cheap car stereo volume control.
Thanks,
Actually, I normally use internal digital volume control of the dac like in ak4497 and es9038pro. I think it is best and most convenient.
This time I am building dual ad1865 dac and want to use something simple for balanced volume control (do not want to end up with another box).
However this is nice preamp concept, thanks!
3. DAC with summing done on transformer level on dac output + stereo volume control -> SE to Balanced board (see universal buffer)-> XLR differential cable to -> modulus 86