[BUILD] Hairball Audio "Lola" Mic Pre - On Sale Now

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mattjhuber said:
I am also having issues with the DI of one of my Lolas; it is making this noise: https://soundcloud.com/mattjhuber/lola-noise

This is the 8th Lola I've built, and the first one with any issue. I reflowed solder joints, did a visual check-through...

Any ideas?

Had someone recently with something similar and it ended up being a bad DI JFET. They used to be J201 and now we use 5457's. He had a bad J201. Could send you new ones if you want to try that.

Email us if so.
 
Hi,

I recently bought 2 lolas preamps, one of them have a strange issue. After a couple of weeks of working fine, it now randomly make a clicking noise even if nothing is plugged in  into the DI input or Mic/Line input( The problem happens when the volume pot is active).
First I've checked for solder joints issues but the problem was the same , then  I've tried to swap the 2 JH op amp from my second unit into the first one and it solved the problem.
Can you give me your advice  ? Where can I order a new JH op amp ?


 
Ataraxia said:
Hi,

I recently bought 2 lolas preamps, one of them have a strange issue. After a couple of weeks of working fine, it now randomly make a clicking noise even if nothing is plugged in  into the DI input or Mic/Line input( The problem happens when the volume pot is active).
First I've checked for solder joints issues but the problem was the same , then  I've tried to swap the 2 JH op amp from my second unit into the first one and it solved the problem.
Can you give me your advice  ? Where can I order a new JH op amp ?

Send us an e-mail.

If your Hardy went bad, we'll replace it.
 
I just made a second Lola and the LED's wouldn't go past 3rd white which was dim. I switched Meter PCB's to check. So I checked LED's with DMM and they all work, but that 3rd one definitely seemed dimmer so I've pulled it. I'll just buy some LED's on ebay to try - any particular type I should get?
 
Okay, replaced LED 3 but still not working. What would stop rest from lighting up? Every LED works, no solder bridges. Should I try MAKING a bridge somewhere to try and get LED 4 upwards working? Any ideas welcome!
 
nicholasdover said:
Okay, replaced LED 3 but still not working. What would stop rest from lighting up? Every LED works, no solder bridges. Should I try MAKING a bridge somewhere to try and get LED 4 upwards working? Any ideas welcome!

Just the one unit?  Does the switch change anything?

If everything looks fine.  I would suspect one of the diodes is bad.  Possibly one of the ICs.

Mike
 
nicholasdover said:
Is there a series thing going on with them where the chain can be broken by one defective part?

The connection to the + rail.  If one of the pads around the last lit one is lifted, that could cause the issue.  Look at the LED PCB, you can see the + legs are all linked with a trace.  Check for continuity.

Mike
 
Looking to see if Mike or someone can help!
I built two Lola pres. LOLA 1 is just amazing...The second LOLA's DI sounds a bit distorted, and has a digital swirling sound at moderate  gain levels.  All the MIC preamp / Line tests completed  on both pres yield identical results, so the issue is definitely isolated to the DI circuit.  I even plugged in my Bass to a Neve RNDI and ran it through the second pre's mic gain circuit  just to check, and it sounded great.

I went back and double checked that all component values and positions matched the parts list and lined up with pre 1.  My guess would be a short on the board, or across a component etc.  I looked for theses issues via a magnified photo, but I don't see anything. 

Here is the digital swirling sound that the DI makes (Sound Cloud):  https://soundcloud.com/sdjudy68/lola-di-noise    You can really hear this sound come alive around 38/42 db of gain and beyond.  The Bass sound comes through on the DI at all levels,  but it's definitely distorted across the entire gain spectrum with little thump compared to my other LOLA DI.  I did email another poster on this page that had a LOLA DI issue, and it turns out he had a cold solder joint ( JFET transistor I believe).  I went back and tipple checked that I had good solder joints on all the transistors / components on the board.    Bad JFET perhaps?  Any help would be grand.  Thanks!
 
sj68sd said:
Looking to see if Mike or someone can help!
I built two Lola pres. LOLA 1 is just amazing...The second LOLA's DI sounds a bit distorted, and has a digital swirling sound at moderate  gain levels.  All the MIC preamp / Line tests completed  on both pres yield identical results, so the issue is definitely isolated to the DI circuit.  I even plugged in my Bass to a Neve RNDI and ran it through the second pre's mic gain circuit  just to check, and it sounded great.

I went back and double checked that all component values and positions matched the parts list and lined up with pre 1.  My guess would be a short on the board, or across a component etc.  I looked for theses issues via a magnified photo, but I don't see anything. 

Here is the digital swirling sound that the DI makes (Sound Cloud):  https://soundcloud.com/sdjudy68/lola-di-noise    You can really hear this sound come alive around 38/42 db of gain and beyond.  The Bass sound comes through on the DI at all levels,  but it's definitely distorted across the entire gain spectrum with little thump compared to my other LOLA DI.  I did email another poster on this page that had a LOLA DI issue, and it turns out he had a cold solder joint ( JFET transistor I believe).  I went back and tipple checked that I had good solder joints on all the transistors / components on the board.    Bad JFET perhaps?  Any help would be grand.  Thanks!

I'm guessing BAD JFET.

Send me a missing parts form requesting JFETs.  We'll send some out.

Hairballaudio.com/missing

Mike
 
Hairball Audio said:
I'm guessing BAD JFET.

Send me a missing parts form requesting JFETs.  We'll send some out.

Hairballaudio.com/missing

Mike
Thanks Mike..I will send one in.
 
Got one built and it only gets sound when the Grayhill gain is on the max setting. The rest of the notches show the same very small output level with a  scratchy noise. Output attenuator seems to function right when grayhill is at the max setting. All switches/lights work. DI does same thing.  I double checked all vertical resistors before soldering, have re-soldered them all. Is there somewhere I should look before resoldering every point on the grayhill switch?
 
0rgazm0 said:
Got one built and it only gets sound when the Grayhill gain is on the max setting. The rest of the notches show the same very small output level with a  scratchy noise. Output attenuator seems to function right when grayhill is at the max setting. All switches/lights work. DI does same thing.  I double checked all vertical resistors before soldering, have re-soldered them all. Is there somewhere I should look before resoldering every point on the grayhill switch?

When you have it at the max gain setting to you get a loud strong signal?  Or is it still low, just more audible then the higher settings?

Mike
 
Very loud signal, sounds ok like it is functioning normally. ( I have 3 other Lolas besides this one )  The other gain settings don't have like a constant noise, but more like I can only see/hear a very small output when a signal comes in. I rechecked the gain resistors and the overall board after the last post but can't find anything.  Also I don't think it should matter but the meter board is not installed yet. Haven't tried re-flowing the grayhill points yet, but they all look pretty good, or at least as good as other stuff I've done that works.
 
0rgazm0 said:
Very loud signal, sounds ok like it is functioning normally. ( I have 3 other Lolas besides this one )  The other gain settings don't have like a constant noise, but more like I can only see/hear a very small output when a signal comes in. I rechecked the gain resistors and the overall board after the last post but can't find anything.  Also I don't think it should matter but the meter board is not installed yet. Haven't tried re-flowing the grayhill points yet, but they all look pretty good, or at least as good as other stuff I've done that works.

I'd check all of your resistor values in the vertical section, reflow joints, check for solder bridges and do same on grayhill. Should be something in there.
 
Well I think I failed at fixing it., while resolderring I burnt the  board between R7 and R8, attached photo. Is this beyond repair? If so do I need to get a whole new board and parts?
 
0rgazm0 said:
Well I think I failed at fixing it., while resolderring I burnt the  board between R7 and R8, attached photo. Is this beyond repair? If so do I need to get a whole new board and parts?

It would be far cheaper to send it in for repair.

http://www.hairballaudio.com/build-support-services
 

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