@birdbox
“Honey why don’t you take a break…you know every time you mess up it’s after you’ve pushed it for too long” - Wife
“I’m fine.” - Me (right before I break MOSFET)
“Honey why don’t you take a break…you know every time you mess up it’s after you’ve pushed it for too long” - Wife
“I’m fine.” - Me (right before I break MOSFET)
So standard practice then. I can relate.
Smarter folks than I will chime in and the collective "we" will get you the right path forward.
Smarter folks than I will chime in and the collective "we" will get you the right path forward.
OOOh, nasty.
you may need to order tons of that from somewhere (not eBay).
or replace both N and P parts with something close enough.
I had the same issue and ended up fitting 2sk1058 and 2sj162 (laterals) with added gate resistors (100z).
works great but needs some extra work and will not fit Mini's PCB.
so another option is to order a couple of Mini sets from the store, use just the FETs and keep the rest for spares.
in the long run it will probably come cheaper.
P.S. Mr. Pass, the most generous soul in this DIY universe.
Chapeau!
Have been doing some listening with the Murata coil… you were right, the sonic differences is very subtle. The ACA Mini was already good, with this small changes, it makes it just that much better. Its spooky how good this sounds. Tried it with the ACP+ as well as the Iron pre. With the ACP+ its a little bit sweeter, treble is amazing. With the Iron pre, the sound has a bit more meat on the bones, bass is a bit more impactful, a bit better mid-range, and a “wider” soundstage. The quotes is because my setup is really a desktop setup.
For those that haven’t done the mods yet, do yourselves a favor and get the kit from Birdbox… between the caps, and the Murata coil, it took me a combined 30 minutes of time to complete, and the changes are worth every penny.
Happy new years Eve friends. May the audio gods bring you more DIY audio project completions that soothes your audio nervosa.
I appreciate all of you in this community, you guys have become a part of my digital tribe…
See you guys in 2025.
Best,
Jose
Thanks for your very kind feedback, Jose!
And Happy new to... all of you!
Claude
And Happy new to... all of you!
Claude
Hi Nelson Pass,
I have a general question that is in part related to your paper introducing the ACA Mini paper:
You note the generation of second harmonic distortion due to the mismatch in gain between n and p parts. Lower gain on the top providing -ve phase distortion and the `C6/R11’ trick offered to increase the gain of the pfet part without upsetting the DC bias so as to provide a closer match between nfet and pfet.
I don’t recall seeing any discussion about messing with source resistors in things like the F5/F5m/F4/M2....
Is the because the mismatch in the 520/9520 parts is more significant than the larger devices uses in the F5 and is this phenomenon only limited to topologies with voltage gain?
Many thanks
I have a general question that is in part related to your paper introducing the ACA Mini paper:
You note the generation of second harmonic distortion due to the mismatch in gain between n and p parts. Lower gain on the top providing -ve phase distortion and the `C6/R11’ trick offered to increase the gain of the pfet part without upsetting the DC bias so as to provide a closer match between nfet and pfet.
I don’t recall seeing any discussion about messing with source resistors in things like the F5/F5m/F4/M2....
Is the because the mismatch in the 520/9520 parts is more significant than the larger devices uses in the F5 and is this phenomenon only limited to topologies with voltage gain?
Many thanks
And another one ready to go to a friend!
Of course with the usual tweaks (4 additional caps and the PS Murata coil)
I let it burn-in for 15h and I am again amazed at how much music this little amp can squeeze out of even very modest bench speakers...
Have a nice day
Claude
Of course with the usual tweaks (4 additional caps and the PS Murata coil)
I let it burn-in for 15h and I am again amazed at how much music this little amp can squeeze out of even very modest bench speakers...
Have a nice day
Claude
Attachments
Alright I am back on track. New MOSFET is installed. Now onto my modifications…I am going to build a simple base and walled enclosure where I will mount binding posts, rca jacks, DC power jack, and led switch. I have a couple questions I would really appreciate your input on:
1. These RCA and power jacks…is the the inner post positive and the outer solder tab ground?
2. Can you tell me which hole (top or bottom) is positive and which is negative for both the rca input and the dc power input.
3. Please help with the led switch. It is a 5 wire so I am assuming it’s three for the switch and two for the light. Can someone help me with where each wire goes?
Thank you so much.
1. These RCA and power jacks…is the the inner post positive and the outer solder tab ground?
2. Can you tell me which hole (top or bottom) is positive and which is negative for both the rca input and the dc power input.
3. Please help with the led switch. It is a 5 wire so I am assuming it’s three for the switch and two for the light. Can someone help me with where each wire goes?
Thank you so much.
1) Center pin signal positive as you stated.
2) Ground vs Positive for power in and signal in.
3) Red and Black are LED power, to the two LED holes. Be sure to get red to anode location marked "+".
Yellow and green are the switch scheme listed. Where as green and white would be the opposite switch scheme. Use a DMM to verify what scheme you want...(button "In is On" vs button "Out is On").
I actually prefer button "Out is On" as I think it looks better when it lights up, however it's slightly counterintuitive as typically (or more common in my experience) button latched in would be on. Here's a picture of button "Out is On"
2) Ground vs Positive for power in and signal in.
3) Red and Black are LED power, to the two LED holes. Be sure to get red to anode location marked "+".
Yellow and green are the switch scheme listed. Where as green and white would be the opposite switch scheme. Use a DMM to verify what scheme you want...(button "In is On" vs button "Out is On").
I actually prefer button "Out is On" as I think it looks better when it lights up, however it's slightly counterintuitive as typically (or more common in my experience) button latched in would be on. Here's a picture of button "Out is On"
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Ok so for the scheme listed red and black to led holes, then green to right hole, yellow in the middle hole, and white in the left hole. Is that correct? Thanks again!
Please can you share the part number and source of the illuminated push button switch?
cheers
cheers
https://www.ebay.com/itm/4044047079..._feznoasuu&var=&widget_ver=artemis&media=COPY
19mm 12V LED ON OFF Push Button Power Switch Latching with Wire Socket Harness
I'll let BeardyWan respond about the switch. I keep second guessing my diagram in fear I'll provide the wrong information.
Apologies, I was actually just interested in the switch. I hadn't realized I had missed a question.
Ok, here's what I put together for the switch I have. Your switch may vary and you can simply figure it out using a multimeter on resistance mode and check the three wires (yellow, green, white in @ross51681 post). Note that the common is the middle of the three switch holes. One of the switch positions connects V+ to the common, while the other position connects ground to the common.
Even if this is wrong (which I hope it isn't), it gives the process of using the schematic, diagram, and switch instructions on how to figure it out. I'll let the experts make the corrections to my errors.
Even if this is wrong (which I hope it isn't), it gives the process of using the schematic, diagram, and switch instructions on how to figure it out. I'll let the experts make the corrections to my errors.