[BUILD] Hairball Audio - Elements

[dobrobson]

Here are a few photos...

 

[Echo North]

You sure the blue and purple on the output transformer are properly connected?

 

[dobrobson]

Double checked and they are. Not sure what happened but now I can't get the thing to pass any signal at all... may need to send these up your way to see if you guys can salvage them for me!

 

[Echo North]

Double checked and they are. Not sure what happened but now I can't get the thing to pass any signal at all... may need to send these up your way to see if you guys can salvage them for me!

Weird.  They are always salvageable and our repair rate for those is super low.

 

[dobrobson]

No worries, I'm sure I just goofed something up. Still really enjoyed the build experience!

 

[Echo North]

No worries, I'm sure I just goofed something up. Still really enjoyed the build experience!

If you want send it on in. We'll get it working for $50.

 

[hillamps]

Just finished up my first Silver Pre this weekend. I love the open design on these that let you configure things on your own. I set it up to similar to a basic 2520  and loaded in a discrete opamp I had. Sound was excellant. I installed a dip socket  under the opamp pins so I could test it with an IC op amp. All I had was a Radio Shack 741 generic op amp but I decided to give it a test. This pre sounds pretty damn good with a cheap opamp in it! I have some "audio" grade IC opamps on order from Mouser and now I can swap them in and out to see how they sound.  I love this open design and the chance to experiment. I can still install a discrete opamp over  the dip socket so I will also test out some discretes. I will be ordering more of these kits real soon. Great product for a technician/musician like me!

 

[Echo North]

Just finished up my first Silver Pre this weekend. I love the open design on these that let you configure things on your own. I set it up to similar to a basic 2520  and loaded in a discrete opamp I had. Sound was excellant. I installed a dip socket  under the opamp pins so I could test it with an IC op amp. All I had was a Radio Shack 741 generic op amp but I decided to give it a test. This pre sounds pretty damn good with a cheap opamp in it! I have some "audio" grade IC opamps on order from Mouser and now I can swap them in and out to see how they sound.  I love this open design and the chance to experiment. I can still install a discrete opamp over  the dip socket so I will also test out some discretes. I will be ordering more of these kits real soon. Great product for a technician/musician like me!

Very cool!

 

[martinswain]

Hi Mike,

It's me again, the guy who posted issues with the Copper module all the way back on page 6 of this thread! Well, my Bronze module works, and I've used it on multiple sessions and love how it sounds, but still can't seem to get my Copper module to work.

I'm at a loss. I have reflowed solder connections on the input and output sections, reflowed solder on the Grayhill switch, checked diodes to see if they were broken, replaced capacitors and re-inserted the op-amp sockets. The issue I'm having is that the signal is really distorted, and will kinda cut out if 'too much' signal passes through on the higher gain settings. The Grayhill switch increases gain no problem, and the output pot turns signal up and down no problem.

Could it possibly be a damaged op-amp? I was thinking about plugging in the op-amp from my Bronze module into the Copper to see if I could rule this out, but didn't want to do so in case I damaged anything. Can I swap the op-amp over to check?

I'm an absolute noob at electronics, as you can probably tell, but I want to persevere and get better so I don't have to bug people all the time. Any help you could give (again) would be a huge benefit.

Thanks.

 

[Echo North]

Hi Mike,

It's me again, the guy who posted issues with the Copper module all the way back on page 6 of this thread! Well, my Bronze module works, and I've used it on multiple sessions and love how it sounds, but still can't seem to get my Copper module to work.

I'm at a loss. I have reflowed solder connections on the input and output sections, reflowed solder on the Grayhill switch, checked diodes to see if they were broken, replaced capacitors and re-inserted the op-amp sockets. The issue I'm having is that the signal is really distorted, and will kinda cut out if 'too much' signal passes through on the higher gain settings. The Grayhill switch increases gain no problem, and the output pot turns signal up and down no problem.

Could it possibly be a damaged op-amp? I was thinking about plugging in the op-amp from my Bronze module into the Copper to see if I could rule this out, but didn't want to do so in case I damaged anything. Can I swap the op-amp over to check?

I'm an absolute noob at electronics, as you can probably tell, but I want to persevere and get better so I don't have to bug people all the time. Any help you could give (again) would be a huge benefit.

Thanks.

You should be able to swap the op-amp.  See if it's an op-amp issue.

Mike

 

[amcmaken]

I built a Bronze pre-amp and it's not passing signal from the mic input. I can confirm it sends phantom power. I've tried the pre with both dynamic and condenser mics to no avail. When I turn up the Grayhill (input) I can hear the gain increase, but no signal from the mic is getting through or being amplified. I texted the DI and it works and sounds great! The Grayhill controls that just fine. There is clearly some sort of disconnect between the input and Grayhill, but I've been over the BOM and Build Guide several times and can't find where I'm missing anything. Any suggestions?

 

[Echo North]

I built a Bronze pre-amp and it's not passing signal from the mic input. I can confirm it sends phantom power. I've tried the pre with both dynamic and condenser mics to no avail. When I turn up the Grayhill (input) I can hear the gain increase, but no signal from the mic is getting through or being amplified. I texted the DI and it works and sounds great! The Grayhill controls that just fine. There is clearly some sort of disconnect between the input and Grayhill, but I've been over the BOM and Build Guide several times and can't find where I'm missing anything. Any suggestions?

The relay, by default, is set to DI.  If your mic input is not working but your DI is, it's because your relay is not flipping on.  The relay has 8 leads, 2 of them are separated from the other 6.  Make sure all 8 leads are soldered.

Also, check your resistors in the relay section and the diode orientation.

Mike

 

[amcmaken]

The relay, by default, is set to DI.  If your mic input is not working but your DI is, it's because your relay is not flipping on.  The relay has 8 leads, 2 of them are separated from the other 6.  Make sure all 8 leads are soldered.

Also, check your resistors in the relay section and the diode orientation.

Mike

Mike,

Thank you so much! I did manage to miss soldering two of the relay leads. My Bronze is working like a charm now!

Sometimes you're staring right at the problem, but just need to know where to look.

 

[Echo North]

Mike,

Thank you so much! I did manage to miss soldering two of the relay leads. My Bronze is working like a charm now!

Sometimes you're staring right at the problem, but just need to know where to look.

Awesome!

 

[tctonn]

I would suspect something external to start. What is your rack brand? Where is the power supply in relation to the rack space your pre is in?  Does moving it to a space further from the supply help?

Mike

Hey Mike,

I finally had a chance to trouble shoot this and by checking all the components and reflowing a few joints. It looks like the noise was likely environmental.  However...

The output signal is really, really low. It sounds good and if I boost it in my DAW the S/N ratio seems good. But the level seems to be 15-20db below what I get out of any of my other gear.

I've done a very thorough check against your build guides and a few pics of successful builds on here.  Any ideas where I should start hunting?

 

[Echo North]

Hey Mike,

I finally had a chance to trouble shoot this and by checking all the components and reflowing a few joints. It looks like the noise was likely environmental.  However...

The output signal is really, really low. It sounds good and if I boost it in my DAW the S/N ratio seems good. But the level seems to be 15-20db below what I get out of any of my other gear.

I've done a very thorough check against your build guides and a few pics of successful builds on here.  Any ideas where I should start hunting?

Do you have the output pot fully clockwise? That is the default position. 

What is your signal source? A mic?

 

[dobrobson]

Got my two Copper repairs a few weeks back and happy to report that they are AMAZING. I'll be using my Pre73 as a doorstop from now on... thanks, Mike!!!

 

[Echo North]

Got my two Copper repairs a few weeks back and happy to report that they are AMAZING. I'll be using my Pre73 as a doorstop from now on... thanks, Mike!!!

Nice!

 

[Siegfried Meier]

Hey guys!

Still struggling with a silver I started a long, long time ago...things got busy.  I've built 4 of these in pretty much the exact same way and they're working flawlessly after several years of use.

However, this one...not so much.  I've replaced quite a number of components and still not happy.  I'm getting hot transistors, but the BA512 opamp doesn't get warm at all - odd, since it has a massive heatsink on there.  My guess is that there's no power getting to the opamp, hence no mic pre output level at all.  Transistors are definitely not backwards, I've checked that a million times to make sure...

Any help much appreciated...I've scoped and checked this thing over many, many times now...

I do hear the relay click when it turns on, and I'm using the EA-10468 input and EA-11148-500 Output transformers.

I'm seeing -15v at the opamp, but no +15...what exactly drives the positive voltage at the opamp?

Thanks,
Sig

EDIT - Ahhhhh a solder bridge at C100!  I looked a hundred times before I even checked with the meter and found it.

 

[Siegfried Meier]

She works beautifully, DI and all.  The only issue I'm having is the 11th and final gain position tends to drop the signal significantly.  What would have caused that?