ACA Redux

My preliminary finding is: the ($49 SMPS ) sold in the diyAudio Store, gives slightly better results than the random $12 SMPS I bought from ebay.
That is great info to have, Mark. Thanks for investigating it.

When I get to build this, I'm hoping to use one or two of three regulated linear PS that I bought used and have available. They are Power One or International Power 24V units that are either 4.8A or 7.2A. For those not familiar with them, they are industrial open frame supplies (often used in machine tools and the like) and if one is a bit patient, they can be had rather economically off of ebay. I bought each of the above for $35 delivered, and they were in very good used condition. An example is shown below.

I've used some lower-powered (0.8A and 3A) 15V and 24V versions of these units to power HD radio tuners and a TDA1387-based DAC, and have been very happy with the results. I am careful to power them off while not in use to avoid needless wasting of energy.

Peter
 

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Progress with my build. I have 2 psu to try 25V 6A toroid into capmx. Or a MW 24v smps. One of the big fan cooled shiny ones. Will be interesting if I can hear a difference, or atleast if it is one worth bothering with.

Thanks to N.Brock for the concept and Mark for the boards.

20220331_192306.jpg
 
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That is great info to have, Mark. Thanks for investigating it.

When I get to build this, I'm hoping to use one or two of three regulated linear PS that I bought used and have available. They are Power One or International Power 24V units that are either 4.8A or 7.2A. For those not familiar with them, they are industrial open frame supplies (often used in machine tools and the like) and if one is a bit patient, they can be had rather economically off of ebay. I bought each of the above for $35 delivered, and they were in very good used condition. An example is shown below.

I've used some lower-powered (0.8A and 3A) 15V and 24V versions of these units to power HD radio tuners and a TDA1387-based DAC, and have been very happy with the results. I am careful to power them off while not in use to avoid needless wasting of energy.

Peter
That is great info to have, Mark. Thanks for investigating it.

When I get to build this, I'm hoping to use one or two of three regulated linear PS that I bought used and have available. They are Power One or International Power 24V units that are either 4.8A or 7.2A. For those not familiar with them, they are industrial open frame supplies (often used in machine tools and the like) and if one is a bit patient, they can be had rather economically off of ebay. I bought each of the above for $35 delivered, and they were in very good used condition. An example is shown below.

I've used some lower-powered (0.8A and 3A) 15V and 24V versions of these units to power HD radio tuners and a TDA1387-based DAC, and have been very happy with the results. I am careful to power them off while not in use to avoid needless wasting of energy.

Peter
Hi Peter

These are indeed quiet supply but make sure to add the required external fuse.

Eric
 
Hi Eric,

Yes, of course. On these larger supplies, I plan to mount an IEC inlet with integrated switch and fuse to the frame. I won’t be making a cutout (the Al plate of the frame is 1/8” thick), but securely lashing the IEC module to the frame using sturdy zip ties through two of the appropriately placed holes that are already there. The IEC modules will also allow me to use up some of the many power cords I’ve accumulated from old computers.
 
So now that this ACA is transformed into mono blocks what is the preferred power supply? Does anyone have suggestions, a part numer or source for said power supplies? Thanks.
I think that the 3.75A version is good enough and overkill for one mono channel. Search for Mean Well gst90a24-p1m, it costs something like 30€ in UE
 
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Good thing your MOSFET pressure-spreading "fender washers" are smaller than the PCB cutout holes. Now when you decide to remove the amp from the heatsink to install the up-facing "glow LEDs" and the power on/off switch, you have a pretty good chance of putting it all back together again. Especially if the fender washers are magnetic and you use a magnetic pickup tool to gently lower them through the cutout hole.
 
Awesome Mark! Thanks for getting this going so quickly. I've been a bit busy lately with moving to a new apartment and starting a new job which is why it's been quiet on my end the past month or so. Thanks for picking up my slack! I am still working on making kits, just a little slower than some would like (including myself!)
 
Hello everybody!

I've put together an interest form to help gauge demand in my kit. I'm not ready to take orders yet, but knowing what the quantity might be will be really helpful.

Please only fill out if you are likely to purchase once offered, this form is meant to limit my personal risk. The target quantity for a first run is 100 kits since that's where the price breaks start to make parts meaningfully cheaper.

https://forms.gle/ooUZA57MEFPZQmgk8

This is not a group buy sign up sheet. Filling out this form does not mean you have ordered or reserved a kit.
 
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