The one on the BOM is unavailable. But a look at the data sheets shows the Cornell Dublier SLPX153M025A9P3 to be equivalent with even better ripple tolerance, and at a good price. Is there something I am missing or unaware of between this and the Panny ECOS1EP153BA on the BOM? If anyone has any input on this re the suitability or audible characteristics of the CD part vs the Panny I'd love to hear it. Cheers!
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I know why! The kit was not announced in the store under "most recent additions" but here in this thread only! And it was listed under the label "Kits".
But now you have the chance to subscribe for a mail as soon as the next batch is available here https://diyaudiostore.com/collections/aca-mini/products/aca-mini-essentials?variant=40119475601481
Good luck!
I can't take credit for that. It was a suggestion made by others much earlier in this thread.
I've had my eye out for a deeper frame that would allow that, but on the sides, as was done by some of the original builders in this thread who frabricated their own frames. Generally I'd rather not have the connectors on top. I've been thinking of running just the speaker pigtails through the side of the frame, by drilling out holes to feed them through, but the frame face pieces are wide and would be challenge for me to drill true freehand. I don't like crooked holes, even slightly so. So it will have to wait until I can access a drill press, or until a better frame opportunity arises.
While it seems to me that this clearly would be of importance for C3 (on the power supply inlet), I'm not understanding why it would be for C2 (output coupling cap). I would have thought that low loss would be more important there, but my understanding of electronics is very limited and I'm sure there are considerations that I am just ignorant of. For example, I would have thought a coupling cap might only need a much more modest value than 15KµF, but I am also sure Nelson had excellent reason(s) for using such a large one in this design.
Few quick questions on this build as I will be receiving the boards today and using my own parts:
1. Can R5 (475 ohm) be replaced with a 470 ohm resistor? have a TON of those on hand.
2. on C2 and C3 I am ordering only through mouser and see only these radial UKT capacitors (647-UKT1E153MRD) fitting the 22mm size. Might be overkill as they are Audio Grade, but wanted to confirm these would be fine and let others know these might be an option through Mouser as the Epcos ones in the manual are not available and snap in options of the same size are out of stock. Much pricier though.
3. Finally, is there any harm in using a regulated 24V power supply? I have an AMB Sigma o11 single rail PSU that I built and use for the ACP and Korg B1.
1. Can R5 (475 ohm) be replaced with a 470 ohm resistor? have a TON of those on hand.
2. on C2 and C3 I am ordering only through mouser and see only these radial UKT capacitors (647-UKT1E153MRD) fitting the 22mm size. Might be overkill as they are Audio Grade, but wanted to confirm these would be fine and let others know these might be an option through Mouser as the Epcos ones in the manual are not available and snap in options of the same size are out of stock. Much pricier though.
3. Finally, is there any harm in using a regulated 24V power supply? I have an AMB Sigma o11 single rail PSU that I built and use for the ACP and Korg B1.
ESR (loss) is virtually identical on the CD vs Panny part. Ripple tolerance is an indicator of robustness and may not be applicable in either use of the part in this design.
@Dneu2011,
1) That should be fine.
2) No problem either, though I think the cap footprint will support 25.4mm diameter caps, which may give you more choices. (Best if you can measure on your pcbs to verify; on mine, there's definitely some room left over with the Panasonic caps)
3) I don't see a problem as long as the linear supply can support the current draw of the ACA mini.
1) That should be fine.
2) No problem either, though I think the cap footprint will support 25.4mm diameter caps, which may give you more choices. (Best if you can measure on your pcbs to verify; on mine, there's definitely some room left over with the Panasonic caps)
3) I don't see a problem as long as the linear supply can support the current draw of the ACA mini.
Hello All:
I made the following diagram to help keep in mind what needs to be done to get to the correct biasing.
Regards,
Charles
I made the following diagram to help keep in mind what needs to be done to get to the correct biasing.
Regards,
Charles
referring to audiosteve's post #1066 above):
My understanding is that low ESR (equiv series resistance) is important for power supply filters, and this is a different parameter than loss, or DF, which would be important for a position in the signal path.
As for ripple tolerance, I think you are correct that its importance in this design may not be important, as the power coming in has already been rectified at the SMPS, so C3 here is not tasked with smoothing out the ripple coming off a rectifier in a linear power supply. So I was wrong in what I said about C3.
My understanding is that low ESR (equiv series resistance) is important for power supply filters, and this is a different parameter than loss, or DF, which would be important for a position in the signal path.
As for ripple tolerance, I think you are correct that its importance in this design may not be important, as the power coming in has already been rectified at the SMPS, so C3 here is not tasked with smoothing out the ripple coming off a rectifier in a linear power supply. So I was wrong in what I said about C3.
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Thank you. I actually took your advice to try 25mm and going to try these from Mouser:
SLPX153M025C7P3
ESR numbers look virtually identical between Panny and CD parts. But I saw no mention of DF or ESL in the Cornell-Dublier data sheet that I could understand vs the Panny. I just don't enough about it. Can anyone else weigh in on this that knows? https://media.digikey.com/pdf/Data Sheets/Panasonic Capacitors PDFs/TS-UP_Rev2010.pdf
https://www.cde.com/resources/catalogs/SLPX.pdf
As for my AMB Sigma o11. It has an Antek as-1220 which is 100VA at 2.5A. Should have enough headroom to try out.
Well, clearly that isn't me. 😉
While I join you in awaiting comments from those more knowledgeable, a point of comparison might be Nichicon KL, a cap that is often mentioned as being very low loss and good for coupling duties in the signal path when a polar cap is needed. KL caps are not an option for the Mini as they don't go up to 15KµF at 25V. Nonetheless, the attached datasheet has their specs for leakage and DF, which could be useful for comparison.
To Dneu2011, none of the idle talk audiosteve and I are having is to imply that Pass has not completely thought through what kind of cap is needed here and has picked ones that are highly suitible, so any that match the specs of those should be excellent, as Dennis Hui has indicated.
You can attenuate the input with a pot since it has a high input impedance. Otherwise, adjusting the feedback will alter the distortion, although it will still tend toward the same character.
Thank you Nelson! I assume plain 10-50K pot before the input cap is what I need.