A slight mismatch will increase second harmonic.
Wether you have the low Idss in the input or feedback position makes a difference, to have it in positive or negative phase. This slightly influences sound stage (in my opinion, depth of sound vs projection of highs).
Papa & ZenMod know this by heart and tell what is best
Wether you have the low Idss in the input or feedback position makes a difference, to have it in positive or negative phase. This slightly influences sound stage (in my opinion, depth of sound vs projection of highs).
Papa & ZenMod know this by heart and tell what is best
my take on the acp+
View attachment preamp betta1.bmp hello I am new to this forum stuff, but here is my preamp circuit based on the acp+ please let me know what you think. Thanks in advance.
View attachment preamp betta1.bmp hello I am new to this forum stuff, but here is my preamp circuit based on the acp+
please let me know what you think. Thanks in advance.Man... I had the ACP up and running and it was sounding sweet.... until I accidentally introduced static after bringing it into my listening space.
I am using a very nice brushed aluminum knob but while listening I went to turn the unit down and felt a light static shock on the knob and the sound went completely out on the right channel..
I’m showing 18V on the voltage check on the right channel and not the 11V it should be. Can someone recommend what parts I should check first?
I was thinking 4n35 or JFETs.
I am using a very nice brushed aluminum knob but while listening I went to turn the unit down and felt a light static shock on the knob and the sound went completely out on the right channel..
I’m showing 18V on the voltage check on the right channel and not the 11V it should be. Can someone recommend what parts I should check first?
I was thinking 4n35 or JFETs.
Updated BOM
Hi folks,
6L6 built a prototype from the BOM we posted a little while back and found an error in the RCA jacks that were specified, so I've updated the BOM and you can find that below.
I am building a prototype from this one this weekend myself too and will let you all know how it goes. Please post feedback from this as soon as you can so we can catch any other issues before we finalize the kit as I've started ordering the parts for the kit assembly with a goal to get these sorted out by the end of this year.
--Tom
Hi folks,
6L6 built a prototype from the BOM we posted a little while back and found an error in the RCA jacks that were specified, so I've updated the BOM and you can find that below.
I am building a prototype from this one this weekend myself too and will let you all know how it goes. Please post feedback from this as soon as you can so we can catch any other issues before we finalize the kit as I've started ordering the parts for the kit assembly with a goal to get these sorted out by the end of this year.
--Tom
You might want to test the MOSFETs before installing so that you have level set that they are indeed good/functional. There was someone on another thread that recently had a bad one for whatever reason and went down a wild debugging road until he realized it was defective. Save yourself some grief and get one of the little inexpensive testers like The Atlas DCA75. I keep mine handy on the bench to remind me whenever I start a build.
--Tom
Very good advice from Tom!
If you can afford the price for a PEAK DCA75 or -better- the DCA75Pro or
the chinese testers - this is well spent money!
Check your active devices for function and also each resistor before soldering into the pcb. This can save you from a lot of troubleshooting.
My experience
Dirk
If you can afford the price for a PEAK DCA75 or -better- the DCA75Pro or
the chinese testers - this is well spent money!
Check your active devices for function and also each resistor before soldering into the pcb. This can save you from a lot of troubleshooting.
My experience
Dirk
Before you spend $125-150 on a PEAK DCA75 (or DCA75 Pro), I'd highly recommend trying a Mega328 tester at ~1/10 the price.
https://www.amazon.com/Aideepen-Mega328-Transistor-Capacitance-Battery/dp/B07RFFMY61/
https://www.amazon.com/Mega328-Component-Transistor-Capacitance-Battery/dp/B089CS8F4H/
Lots of people around here use them (myself included). They work great are an absolute steal IMO.
You can also get it with a color screen & minigrabber leads if you like, for more like $30
https://www.amazon.com/Longruner-Pocketable-Multifunctional-Backlight-Transistor/dp/B07C5LC486/
https://www.amazon.com/Aideepen-Mega328-Transistor-Capacitance-Battery/dp/B07RFFMY61/
https://www.amazon.com/Mega328-Component-Transistor-Capacitance-Battery/dp/B089CS8F4H/
Lots of people around here use them (myself included). They work great are an absolute steal IMO.
You can also get it with a color screen & minigrabber leads if you like, for more like $30
https://www.amazon.com/Longruner-Pocketable-Multifunctional-Backlight-Transistor/dp/B07C5LC486/
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Didn't mean to slight the Mega. I have that one too and it does work great. Point is, get one of these to prevent obvious issues ahead of time.
--Tom