Well, I want to start this post by saying:
OH! MY GOD!!!
I have spent the last two hours listening to my *almost* finished ACA! The sound is just sublime! Such warmth and body, such deep and coherent bass, nice detailed highs. Also, the sound is very even throughout the frequency range... something my 'bigger' class D amp is not that good at. It's just amazing sound, with any type of music I play.
I listened to it in my living room with my 4 Ohm 87 dB efficient Totem Rainmakers, and it is producing all the volume I would want or need, and that is with the 5W of the 19V PSU / 10V Bias setting (more on this later!). So the fellows getting the bigger 24V PSU / 12 Bias with 8W output: do not worry about this AMP's capacity to drive your speakers loud enough for serious listening on even larger spaces. It's just that good! And with such simplicity in its design, that it is downright scary! It's truly the work of genius! (but that we all already knew!
).
For those that have been following and helping with my adventure (for those that haven't, I've been building my own chassis): the inner cabling did not end up that good... my PCB positioning is not the greatest for that, I'll post some pictures tomorrow with better light.
Still, my original worries about the heatsinks not being quite sufficient apparently were well funded: the inner aluminum 'Ls' are getting around 58º, and the outer heatsink is reaching 54º. Still, I'm somehow proud of the design I made incorporating the top lid as part of the dissipation area. It's reaching 45º, so its helping with a large surface for heat exchange.
Here's the design I'm talking about:
So, my kit will forever live as a 19V / 10V Bias AMP, because I cannot go any higher in temps or I'll turn my AMP into a stove. Also, the Power Resistors are getting to around 63º, which is really hot! So I'm regretting not having lifted them a bit. I guess other's see similar temps for those resistors? (as they are not being cooled by anything other than air flow in the chassis).
So, here it is, ready for the first listen:
My Kira knows its going to reach 50º and is waiting to curl by its side
Once everything looked like working, I moved it to my living room, replacing a 150W NuPrime ST-10 and hooked to a NuPrime DAC-10 / PRE configured to output a max of 4V on the RCA connectors (high setting). The amp is able to deliver all the volume I need:
I'd like to tell the very beginning of this story, which I haven't shared fully before:
When the 'first batch' of pre orders became available a few months ago, I spent a few days deciding if I could fit the ACA into my budget and time, if I had the skills required.. the usual decision making process. By the time I had an answer, I came to the store and as I was making the purchase, Jason was removing the pre-orders as they have had such success that they were terminating the pre orders a day early. I was really sad and upset with myself for having taken so long to make up my mind.
Just then, Jason wrote with a generous offer to help get me in the first batch or early in the second, depending on availability. Very grateful, I remade the process only to find out that shipping to my country would cost around US$200.
While we were discussing options, 6L6... whom by his unending stream of help guides alone deserves a statue in the generosity hall of fame... wrote saying he had a spare kit of electronic parts and older model PCBs for the ACA that Mr. Pass had given him. He said, I'll never forget: "Papa Pass gave these to me, and I'm sending them to you, so it's like Papa Nelson giving them to you himself!"
.
But 6L6 did not send the electronics and PCBs... alone. He also sent all the connectors and switches, all the cabling (which is also hard to find of good quality locally). He included the Keratherm Transistor Insulators, and if all that was not enough, he also included a PSU and the kindest handwritten note that ended saying: here you have 99% of what you need to build the ACA Amp.
6L6 I am deeply grateful and forever in your debt (even more so than all the people you help here at DIY), and I can only hope that in time I will be able to pay-it-forward as you, Jason, Mr. Pass and so many others do here in this incredible community.
I cannot express my gratitude heartily enough, and I hope that the craftsmanship of my ACA is able to reflect in an small fraction your generosity and Mr. Pass' genius. I certainly gave it my best, inspired to live up to what you have gifted me.
Thank you truly for this most wonderful gift of music in our lives, and the opportunity to share the process with my dad (who has been counseling me since the beginning).
6L6, I send you a big hug from the middle of the world!
I'll finish up the vents and front window tomorrow and test some other speakers to find the best match for the amp. I'll post the inner pictures as well.
Best regards,
Rafa.
OH! MY GOD!!!
I have spent the last two hours listening to my *almost* finished ACA! The sound is just sublime! Such warmth and body, such deep and coherent bass, nice detailed highs. Also, the sound is very even throughout the frequency range... something my 'bigger' class D amp is not that good at. It's just amazing sound, with any type of music I play.
I listened to it in my living room with my 4 Ohm 87 dB efficient Totem Rainmakers, and it is producing all the volume I would want or need, and that is with the 5W of the 19V PSU / 10V Bias setting (more on this later!). So the fellows getting the bigger 24V PSU / 12 Bias with 8W output: do not worry about this AMP's capacity to drive your speakers loud enough for serious listening on even larger spaces. It's just that good! And with such simplicity in its design, that it is downright scary! It's truly the work of genius! (but that we all already knew!
).For those that have been following and helping with my adventure (for those that haven't, I've been building my own chassis): the inner cabling did not end up that good... my PCB positioning is not the greatest for that, I'll post some pictures tomorrow with better light.
Still, my original worries about the heatsinks not being quite sufficient apparently were well funded: the inner aluminum 'Ls' are getting around 58º, and the outer heatsink is reaching 54º. Still, I'm somehow proud of the design I made incorporating the top lid as part of the dissipation area. It's reaching 45º, so its helping with a large surface for heat exchange.
Here's the design I'm talking about:
So, my kit will forever live as a 19V / 10V Bias AMP, because I cannot go any higher in temps or I'll turn my AMP into a stove. Also, the Power Resistors are getting to around 63º, which is really hot! So I'm regretting not having lifted them a bit. I guess other's see similar temps for those resistors? (as they are not being cooled by anything other than air flow in the chassis).
So, here it is, ready for the first listen:
My Kira knows its going to reach 50º and is waiting to curl by its side
Once everything looked like working, I moved it to my living room, replacing a 150W NuPrime ST-10 and hooked to a NuPrime DAC-10 / PRE configured to output a max of 4V on the RCA connectors (high setting). The amp is able to deliver all the volume I need:
I'd like to tell the very beginning of this story, which I haven't shared fully before:
When the 'first batch' of pre orders became available a few months ago, I spent a few days deciding if I could fit the ACA into my budget and time, if I had the skills required.. the usual decision making process. By the time I had an answer, I came to the store and as I was making the purchase, Jason was removing the pre-orders as they have had such success that they were terminating the pre orders a day early. I was really sad and upset with myself for having taken so long to make up my mind.
Just then, Jason wrote with a generous offer to help get me in the first batch or early in the second, depending on availability. Very grateful, I remade the process only to find out that shipping to my country would cost around US$200.
While we were discussing options, 6L6... whom by his unending stream of help guides alone deserves a statue in the generosity hall of fame... wrote saying he had a spare kit of electronic parts and older model PCBs for the ACA that Mr. Pass had given him. He said, I'll never forget: "Papa Pass gave these to me, and I'm sending them to you, so it's like Papa Nelson giving them to you himself!"
.But 6L6 did not send the electronics and PCBs... alone. He also sent all the connectors and switches, all the cabling (which is also hard to find of good quality locally). He included the Keratherm Transistor Insulators, and if all that was not enough, he also included a PSU and the kindest handwritten note that ended saying: here you have 99% of what you need to build the ACA Amp.
6L6 I am deeply grateful and forever in your debt (even more so than all the people you help here at DIY), and I can only hope that in time I will be able to pay-it-forward as you, Jason, Mr. Pass and so many others do here in this incredible community.
I cannot express my gratitude heartily enough, and I hope that the craftsmanship of my ACA is able to reflect in an small fraction your generosity and Mr. Pass' genius. I certainly gave it my best, inspired to live up to what you have gifted me.
Thank you truly for this most wonderful gift of music in our lives, and the opportunity to share the process with my dad (who has been counseling me since the beginning).
6L6, I send you a big hug from the middle of the world!
I'll finish up the vents and front window tomorrow and test some other speakers to find the best match for the amp. I'll post the inner pictures as well.
Best regards,
Rafa.
Well, I want to start this post by saying:
OH! MY GOD!!!
I have spent the last two hours listening to my *almost* finished ACA! The sound is just sublime! Such warmth and body, such deep and coherent bass, nice detailed highs. Also, the sound is very even throughout the frequency range... something my 'bigger' class D amp is not that good at. It's just amazing sound, with any type of music I play.
I listened to it in my living room with my 4 Ohm 87 dB efficient Totem Rainmakers, and it is producing all the volume I would want or need, and that is with the 5W of the 19V PSU / 10V Bias setting (more on this later!). So the fellows getting the bigger 24V PSU / 12 Bias with 8W output: do not worry about this AMP's capacity to drive your speakers loud enough for serious listening on even larger spaces. It's just that good! And with such simplicity in its design, that it is downright scary! It's truly the work of genius! (but that we all already knew!
For those that have been following and helping with my adventure (for those that haven't, I've been building my own chassis): the inner cabling did not end up that good... my PCB positioning is not the greatest for that, I'll post some pictures tomorrow with better light.
Still, my original worries about the heatsinks not being quite sufficient apparently were well funded: the inner aluminum 'Ls' are getting around 58º, and the outer heatsink is reaching 54º. Still, I'm somehow proud of the design I made incorporating the top lid as part of the dissipation area. It's reaching 45º, so its helping with a large surface for heat exchange.
Here's the design I'm talking about:
So, my kit will forever live as a 19V / 10V Bias AMP, because I cannot go any higher in temps or I'll turn my AMP into a stove. Also, the Power Resistors are getting to around 63º, which is really hot! So I'm regretting not having lifted them a bit. I guess other's see similar temps for those resistors? (as they are not being cooled by anything other than air flow in the chassis).
So, here it is, ready for the first listen:
My Kira knows its going to reach 50º and is waiting to curl by its side
Once everything looked like working, I moved it to my living room, replacing a 150W NuPrime ST-10 and hooked to a NuPrime DAC-10 / PRE configured to output a max of 4V on the RCA connectors (high setting). The amp is able to deliver all the volume I need:
I'd like to tell the very beginning of this story, which I haven't shared fully before:
When the 'first batch' of pre orders became available a few months ago, I spent a few days deciding if I could fit the ACA into my budget and time, if I had the skills required.. the usual decision making process. By the time I had an answer, I came to the store and as I was making the purchase, Jason was removing the pre-orders as they have had such success that they were terminating the pre orders a day early. I was really sad and upset with myself for having taken so long to make up my mind.
Just then, Jason wrote with a generous offer to help get me in the first batch or early in the second, depending on availability. Very grateful, I remade the process only to find out that shipping to my country would cost around US$200.
While we were discussing options, 6L6... whom by his unending stream of help guides alone deserves a statue in the generosity hall of fame... wrote saying he had a spare kit of electronic parts and older model PCBs for the ACA that Mr. Pass had given him. He said, I'll never forget: "Papa Pass gave these to me, and I'm sending them to you, so it's like Papa Nelson giving them to you himself!"
But 6L6 did not send the electronics and PCBs... alone. He also sent all the connectors and switches, all the cabling (which is also hard to find of good quality locally). He included the Keratherm Transistor Insulators, and if all that was not enough, he also included a PSU and the kindest handwritten note that ended saying: here you have 99% of what you need to build the ACA Amp.
6L6 I am deeply grateful and forever in your debt (even more so than all the people you help here at DIY), and I can only hope that in time I will be able to pay-it-forward as you, Jason, Mr. Pass and so many others do here in this incredible community.
I cannot express my gratitude heartily enough, and I hope that the craftsmanship of my ACA is able to reflect in an small fraction your generosity and Mr. Pass' genius. I certainly gave it my best, inspired to live up to what you have gifted me.
Thank you truly for this most wonderful gift of music in our lives, and the opportunity to share the process with my dad (who has been counseling me since the beginning).
6L6, I send you a big hug from the middle of the world!
I'll finish up the vents and front window tomorrow and test some other speakers to find the best match for the amp. I'll post the inner pictures as well.
Best regards,
Rafa.
Rafa...what a wonderful and touching story! Jim, (6L6) has shared his time with me also. What a great guy! We're truly lucky to have him.
A+ on your build. Looks very nice and I bet sounds as good.
Plus one for that. Well done Rafa, now enjoy and plan the next project!
great !
I told ya that these DiyA guys are Sissies .... soft at heart
Yeah we are. I liked Kira
I use Cardas. It's kind of expensive, but that's what I have always used. Sounds the best to me.
Cardas Solder
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@RafaPolit well done with your build. You've embraced the DIY dream a lot more than I'd like to for my first go, so kudos to you.
I still think there's sense in perforating (or venting by some other means) the top plate so that the heat from the internal fins can simply rise straight out of the enclosure. You probably just want to enjoy your handiwork for a while before getting into further mods.
The parts for my units have just made landfall in Australia (according to tracking info), so this is some great inspiration. Thanks.
Pass DIY Addict
Joined 2000
Paid Member
I like the Kester 44 63/37. Can't remember which AWG I have but 24 seems like a good choice. Perhaps one of the experts will check in.
24-6337-0010 Kester Solder | Soldering, Desoldering, Rework Products | DigiKey
Jim
I've used the Kester Rosin Cored 63/37 0.031" Diameter on a few audio projects and it flows nicely. I can't say how it sounds but the few things I've built using it sound very good
Kester 24-6337-8800 50 Activated Rosin Cored Wire Solder Roll, 245 No-Clean, 63/37 Alloy, 0.031" Diameter: Amazon.com: Industrial & Scientific
Kester 24-6337-8800 50 Activated Rosin Cored Wire Solder Roll, 245 No-Clean, 63/37 Alloy, 0.031" Diameter: Amazon.com: Industrial & Scientific
Rafa -
Your contribution to this thread by making a completely custom build (in very fast time) and well documented is absolutely wonderful!! Please accept my sincere thanks for a job well done. It's a beautiful build and an incredible part of this thread.
eres increíble! (You're Awesome!)
Your contribution to this thread by making a completely custom build (in very fast time) and well documented is absolutely wonderful!! Please accept my sincere thanks for a job well done. It's a beautiful build and an incredible part of this thread.
eres increíble! (You're Awesome!)
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