cmac

Re: [BUILD] Hairball Audio - Elements
« Reply #420 on: December 10, 2019, 11:36:51 AM »
Do you have another op-amp you can swap in to rule out a bad op-amp?

Alright, I finally got swapping a BA512 op amp from one of my working Copper Pres. It worked! Perhaps it got fried when the capacitors C505-506 blew? Anyway, that is definitely the issue, I tested the input output knobs and Pad switch. The preamp worked perfectly with the new Op Amp. I am to assume the easiest solution is to order a new one from hairball? They are so small I imagine it would be difficult, if not impossible, to troubleshoot? Glad its figured out! As always, thanks for the help.

Clinton


Hairball Audio

Re: [BUILD] Hairball Audio - Elements
« Reply #421 on: December 10, 2019, 04:40:52 PM »
Alright, I finally got swapping a BA512 op amp from one of my working Copper Pres. It worked! Perhaps it got fried when the capacitors C505-506 blew? Anyway, that is definitely the issue, I tested the input output knobs and Pad switch. The preamp worked perfectly with the new Op Amp. I am to assume the easiest solution is to order a new one from hairball? They are so small I imagine it would be difficult, if not impossible, to troubleshoot? Glad its figured out! As always, thanks for the help.

Clinton

Not impossible, but I find it easier just to get a new one.

Mike
Hairball Audio, LLC
DIY Parts and Kits
https://hairballaudio.com

Top secret stuff and upcoming releases:
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EmoRiot

Re: [BUILD] Hairball Audio - Elements
« Reply #422 on: March 04, 2020, 12:44:44 AM »
Hey there Hairball. I started my build tonight and everything was going swimmingly stuffing my PCB with resistors until I got to the last three. Shown below...



But the color bands on the resistors I have indicate, if I'm reading them correctly, that I have two 2M resistors and one 1M resistor - not 200k and 100k. I've got a picture of my resistors below as they were in my kit. Do I have the wrong resistors or am I reading these bands wrong?


EmoRiot

Re: [BUILD] Hairball Audio - Elements
« Reply #423 on: March 04, 2020, 01:37:09 AM »
Aha! I figured it out.

The orange band looked yellow to me. But if I recognize it at orange then the values make sense and I'm off and on my way with diodes and transistors.

Fuzz Face

Re: [BUILD] Hairball Audio - Elements
« Reply #424 on: March 04, 2020, 08:08:11 AM »
Aha! I figured it out.

The orange band looked yellow to me. But if I recognize it at orange then the values make sense and I'm off and on my way with diodes and transistors.
Do you have a DMM? As stated in the build guide, you should double check resistors by measuring them. Then there’s no question

EmoRiot

Re: [BUILD] Hairball Audio - Elements
« Reply #425 on: March 04, 2020, 12:57:06 PM »
Do you have a DMM? As stated in the build guide, you should double check resistors by measuring them. Then there’s no question

Yeah I had been testing them all night but the readings on those three were a little weird - but only when I was unsure of the bands. Once I set my DMM correctly for the expected resistance it all read as expected. Thanks!

Re: [BUILD] Hairball Audio - Elements
« Reply #426 on: April 26, 2020, 10:58:08 PM »
Just finished my 2nd Copper mic pre kit (built the first one about 8 mos ago). Anyway, I've noticed that the first one I built has a significantly reduced output compared to the new one. Any thoughts on what might be causing this? I've included a picture showing how vastly different they are from each other; as shown both preamps are producing the same amount of signal from the same microphone with the same cable.

Thank you!

Ian

Hairball Audio

Re: [BUILD] Hairball Audio - Elements
« Reply #427 on: April 27, 2020, 04:15:46 PM »
Swap the op-amps, see if the issue follows the op-amp.

Just finished my 2nd Copper mic pre kit (built the first one about 8 mos ago). Anyway, I've noticed that the first one I built has a significantly reduced output compared to the new one. Any thoughts on what might be causing this? I've included a picture showing how vastly different they are from each other; as shown both preamps are producing the same amount of signal from the same microphone with the same cable.

Thank you!

Ian
Hairball Audio, LLC
DIY Parts and Kits
https://hairballaudio.com

Top secret stuff and upcoming releases:
http://instagram.com/Hairballaudio
http://facebook.com/hairballaudio

Re: [BUILD] Hairball Audio - Elements
« Reply #428 on: April 27, 2020, 08:05:13 PM »
Swap the op-amps, see if the issue follows the op-amp.

Thanks for the prompt reply. Good news. It turns out i'm just an idiot! I failed to take into consideration that the louder of the two preamps was also hitting my FET Rack before hitting my converters, and even in "bypass" mode and at unity gain was still bumping up the signal a few db.

Thanks again for your help!

Ian

Hairball Audio

Re: [BUILD] Hairball Audio - Elements
« Reply #429 on: April 30, 2020, 01:08:15 PM »
Thanks for the prompt reply. Good news. It turns out i'm just an idiot! I failed to take into consideration that the louder of the two preamps was also hitting my FET Rack before hitting my converters, and even in "bypass" mode and at unity gain was still bumping up the signal a few db.

Thanks again for your help!

Ian

Nice!  8)
Hairball Audio, LLC
DIY Parts and Kits
https://hairballaudio.com

Top secret stuff and upcoming releases:
http://instagram.com/Hairballaudio
http://facebook.com/hairballaudio


Re: [BUILD] Hairball Audio - Elements
« Reply #430 on: August 18, 2020, 07:09:51 PM »
just finished two copper preamps, everything works wonderfully(I Think) DI's. mic pre,and phantom power, BUT there was an audible "click" happening when I would have the phantom power engaged. This is NOT a click from pressing or engaging the switches this was a "click" ONLY when the phantom power was engaged. IT HAS gone away , BUT I am curious what this could have been. I was in BOTH preamps, but everything seems fine now...................

cmac

Re: [BUILD] Hairball Audio - Elements
« Reply #431 on: October 18, 2020, 01:24:01 PM »
Hello,

I repaired one of my Copper Pre's last December. Capacitor C505 and C506 were replaced and a new Op Amp was ordered, it did the trick! It continued to work for many months, but now I am getting no signal. Tried multiple cables and mics, its definitely the Preamp. I swapped out the Op Amp from this non working preamp into another Copper preamp I have and it worked. So the Op Amp in this bad copper module is not the issue. I can try test points, any other suggestions would be appreciated!

Clinton