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

[Echo North]

Hi Mike, thanks for your response.

Good to know that the red light doesn't mean it's distorting. But the problem is then, with something dynamic like a vocal, when a loud part gets up into the red it throws out a nasty midrange peak, it almost sounds like the 600-1.5kHz seems to just poke right out. It does sound like it's distorting.

To avoid the vocal hitting the red (having the very loudest parts only getting up into that area) the rest of the vocal is only coming in at say -35dB in PT and isn't really showing on the lola meters...

If your source is that dynamic you need to split the difference or add compression.  This should be true of any mic pre. If you whisper into it and set the level, then scream...you're going to clip it.

Unless I'm missing something?

Or you may just have an issue with your build.

Mike

 

[Echo North]

Also what are your converter inputs? Do that have a gain stage?

Mike

 

[shortyboyboy]

Hey Gang,

Is there a youtube video or website link someone could post here to help me try and trace down how I can find a bad signal on my lola?  I have checked all of the parts and they seem to be in their right places.  I tried resoldering spots that looked like they could have been dead solder points with no luck of finding the issue.

I still get about 2 seconds of working signal from the preamp before it shuts off.  All of the lights and everything work.

Thank you so much!  I really look forward to figuring this problem out

 

[TillM]

Did you test the DI signal whether you get signal at the DI Input?
Do you use a diy DOA or did you buy them already soldered ?

 

[shortyboyboy]

Yes, the DI signal does work for only a couple of seconds as well. I did build the DOAs myself. Is that something I can check?

 

[TillM]

defnitly check your DOAs.
If its possible that you have some working DOAs check them.
Is your Lunchbox okay ? Maybe there is a problem with the voltage.
But first of all I would check the DOAs

 

[PhilsPlace]

Just finished a pair of Lola pres, BA512 op amps.  They sound amazing and everything functions but the meter(kinda). When operating clean I'm only able to see the 1st or 2nd light and the values do not correspond with the meters in my DAW. It's only when I crank both gain and output full CW do see the orange lights. I've been through every component and solder joint of both meter boards 5 times now, and they are identical and correct. Is there anything on the main pcb  that would cause this, and if not, is there a series of diagnostics to help isolate the issue? Any help would be greatly appreciated.

Thanks
Philip

 

[TillM]

DAW Input and Preamp Input are two different shoes.
Check the solder joints on the IC transistor.
Maybe you solder a LED the wrong way.

 

[Echo North]

Just finished a pair of Lola pres, BA512 op amps.  They sound amazing and everything functions but the meter(kinda). When operating clean I'm only able to see the 1st or 2nd light and the values do not correspond with the meters in my DAW. It's only when I crank both gain and output full CW do see the orange lights. I've been through every component and solder joint of both meter boards 5 times now, and they are identical and correct. Is there anything on the main pcb  that would cause this, and if not, is there a series of diagnostics to help isolate the issue? Any help would be greatly appreciated.

Thanks
Philip

Your DAW (dbFS) and Lola (dbu) have completely different scales.  There can be as much as a 20dB difference between the scales.

 

[brazos]

Hi there, any help would be appreciated.  I finished my first Lola build and everything is excellent except for 2 problems:

1. D/I input.  When I plug an electric guitar into the D/I, I get highly distorted pulsating noise that is affected by playing the guitar, but is not clean signal in any respect.  When I pull the cable out slightly so the tip of the cable is touching the ring of the jack, I get normal signal.  I hear the relay click when I plug in as expected.

2. Attenuator knob.  When turned all the way down, the signal never goes to zero.  In fact, the lowest output is when the attenuator is set to somewhere in the middle.  High is high, low is high, and middle is very low but not zero.

Any suggestions would be greatly appreciated.

Thanks 

 

[Potato Cakes]

Hi there, any help would be appreciated.  I finished my first Lola build and everything is excellent except for 2 problems:

1. D/I input.  When I plug an electric guitar into the D/I, I get highly distorted pulsating noise that is affected by playing the guitar, but is not clean signal in any respect.  When I pull the cable out slightly so the tip of the cable is touching the ring of the jack, I get normal signal.  I hear the relay click when I plug in as expected.

2. Attenuator knob.  When turned all the way down, the signal never goes to zero.  In fact, the lowest output is when the attenuator is set to somewhere in the middle.  High is high, low is high, and middle is very low but not zero.

Any suggestions would be greatly appreciated.

Thanks

Bad solder joint/Bad component placement/Incorrect component orientation/Incorrect transformer wiring.

Thanks!

Paul

 

[Echo North]

Maybe a short are bad pad on the tpad.

The Tpad will never be totally zero.  However, it should get quieter as you rotate CCW. 

For the DI, maybe a bad FET Buffer. We can send a new pair if you like.

Mike

 

[bugcheck]

Hi Mike,

I'm having a DI input problem that's pretty similar to the one brazos mentions just above (reply #329) with one of the two Lola's I just completed.  The other one is working normally. 

With a bass (well really, low side of a Chapman Stick) plugged into the DI with an instrument cable, I'm getting distorted audio.  I have similar symptoms to brazos when I pull the cable out slightly: signal is much less distorted (although perhaps still a bit fuzzy), and stronger (louder).  I've scrutinized the solder joints, and re-flowed a number of them, and did an initial check for any misplaced parts in the DI area.  I don't see obvious errors.  The same instrument cable into the DI of the other Lola I just completed gives me good clear audio as expected.

Also, I tested the balanced input of the problem Lola with both a dynamic and a condenser mic, and this is working normally.  Seemingly the op-amps and rest of the circuit are OK.

Seems a bit curious that my problem is nearly the same as brazos'.  In his case you suggested possible bad FET Buffer.  Any reason to think this might be related?  Any help is greatly appreciated.

Thanks,
Gary

Edit: user brazos, not Potato Cakes

 

[Echo North]

Hi Mike,

I'm having a DI input problem that's pretty similar to the one brazos mentions just above (reply #329) with one of the two Lola's I just completed.  The other one is working normally. 

With a bass (well really, low side of a Chapman Stick) plugged into the DI with an instrument cable, I'm getting distorted audio.  I have similar symptoms to brazos when I pull the cable out slightly: signal is much less distorted (although perhaps still a bit fuzzy), and stronger (louder).  I've scrutinized the solder joints, and re-flowed a number of them, and did an initial check for any misplaced parts in the DI area.  I don't see obvious errors.  The same instrument cable into the DI of the other Lola I just completed gives me good clear audio as expected.

Also, I tested the balanced input of the problem Lola with both a dynamic and a condenser mic, and this is working normally.  Seemingly the op-amps and rest of the circuit are OK.

Seems a bit curious that my problem is nearly the same as brazos'.  In his case you suggested possible bad FET Buffer.  Any reason to think this might be related?  Any help is greatly appreciated.

Thanks,
Gary

Edit: user brazos, not Potato Cakes

Fill out a missing parts form: Hairballaudio.com/missing

Request a new set of FET buffers.

Mike

 

[bugcheck]

Just to follow up - replacing the FET buffers did solve my Lola DI issue.  Thanks for the help, Mike!

 

[mjlaudio]

I just finished a Lola Preamp and everything works except the meters. When I switch between ppm and vu i get slight flashes. When I max out the unit nothing changes. I checked for bad solder joints and for placement everything looks right. I do notice that the opamps and ic are getting warm after a few min.

Any ideas?

 

[Potato Cakes]

I just finished a Lola Preamp and everything works except the meters. When I switch between ppm and vu i get slight flashes. When I max out the unit nothing changes. I checked for bad solder joints and for placement everything looks right. I do notice that the opamps and ic are getting warm after a few min.

Any ideas?

Did you meter to make sure proper voltage is getting the the meter board? If the preamp and DI are working properly, then the problem is on the meter board or the at the header on the main board going to the meter board. Should be pretty easy to find as the problem area is narrowed down significantly.

Thanks!

Paul

 

[Echo North]

I just finished a Lola Preamp and everything works except the meters. When I switch between ppm and vu i get slight flashes. When I max out the unit nothing changes. I checked for bad solder joints and for placement everything looks right. I do notice that the opamps and ic are getting warm after a few min.

Any ideas?

Also, confirm your ICs are not mixed up and they are in the right direction.

Op-amps should get a little warm.

Mike

 

[mjlaudio]

Nevermind. Still looking for errors.

 

[hiegdk]

I have a Lola that has cooked R36 and R37 3 times now (guessing a faulty DOA). This last time when I was pulling the cooked R36 the trace between it and the DOA pin came with it  :'(

Can anyone think of a way I can fix the trace or is this Lola toast?