Black Lion B173 Problem
- Thread starter smilan
- Start date
Help Support GroupDIY Audio Forum:
Is that a Neve clone?
If so you probably need to correctly set the Bias so that you have symmetrical clipping.
There should be a trimpot inside the unit to set the Bias point
If so you probably need to correctly set the Bias so that you have symmetrical clipping.
There should be a trimpot inside the unit to set the Bias point
It supposed to be a Neve clone, but it's not a 1:1 clone.
There is no trimpot inside the unit.
Here's a drawing of the mic amp section that I made by tracing the SMD components, so I hope it's right...
The clipping on the negative half of the waveform starting at the collector of Q11, so I guess the biasing of this transistor should be adjust.
On idle the voltages on Q11 are: Collector: 12.45V, Emitter: 10.9V, Bass: 11.6v.
I don't sure how to calculate the right values for biasing this transistor.
Last edited:
The supply voltage is 24V.
I've managed to fix it by replacing R51 with a trimmer pot and by fine tuning it now the signal brakes in the two ends of the signal at the same time.
You might want to replace that with a fixed resistor of whatever value the trimmer is set to - those things are rated for minimal power, and i wouldn't trust one in that position, for the long term. But glad to hear you found a solution!
A really important thing, did you contact Black Lion describing the problem?
Yesterday I've sent a message from this link to Black Lion support team, I'm still waiting to hear from them...
Hi !
Oh man, you can't imagine how much troubles I had with these pres. I was so much into BLA products, Digi003 hyper dupper custom, Auteur pres, B173...
You seem to be the first who talks about it or BLA is pretty efficient to delete every trace of their failure on the B173.
I bought a pair when they came out, BLA replaced them 3 times. 3 F*%$ing times (imagine shipping costs from europe to US) and the 3rd they didn't even ask for sending back the faulty one and then just quit the boat, pretending the problem came from my PSU or my main power supply in the building... Really ?!? So why my API, Neve, SSL pres work perfectly as expected ? I build pres from scratch for about 10y so we can talk about it guys.
Finally about the 3x B173 I own, only one performs correctly in mic config, 1/3 successful is a shame !
Leaving me alone without solving their design problem was the final stroke, I banned Black Lion Audio from my futur orders.
The 3 modules are excellent in DI mode. But man, mic mode is a nightmare, unreliable ! For a correct use, you must always start with pots at minimum (full counter-clockwise), and even doing this, problems are coming fast while heating. On the bad couple, I never had the negative part of the sinus, saturation is not pleasing to hear so you turn them off and use them for leveling the pinball.
Reading this post, I've nothing to loose so, I'll try the "Smilan mod" with a trimmer and I'll get back to you asap.
Meanwhile, here's the only info I've been able to find since 3-4 years, the Cinemag transformer's datasheet.
If anyone has more info about the lack of negative part of the signal and how to solve the problem, my ears are wide opened.
Thks
A.
Oh man, you can't imagine how much troubles I had with these pres. I was so much into BLA products, Digi003 hyper dupper custom, Auteur pres, B173...
You seem to be the first who talks about it or BLA is pretty efficient to delete every trace of their failure on the B173.
I bought a pair when they came out, BLA replaced them 3 times. 3 F*%$ing times (imagine shipping costs from europe to US) and the 3rd they didn't even ask for sending back the faulty one and then just quit the boat, pretending the problem came from my PSU or my main power supply in the building... Really ?!? So why my API, Neve, SSL pres work perfectly as expected ? I build pres from scratch for about 10y so we can talk about it guys.
Finally about the 3x B173 I own, only one performs correctly in mic config, 1/3 successful is a shame !
Leaving me alone without solving their design problem was the final stroke, I banned Black Lion Audio from my futur orders.
The 3 modules are excellent in DI mode. But man, mic mode is a nightmare, unreliable ! For a correct use, you must always start with pots at minimum (full counter-clockwise), and even doing this, problems are coming fast while heating. On the bad couple, I never had the negative part of the sinus, saturation is not pleasing to hear so you turn them off and use them for leveling the pinball.
Reading this post, I've nothing to loose so, I'll try the "Smilan mod" with a trimmer and I'll get back to you asap.
Meanwhile, here's the only info I've been able to find since 3-4 years, the Cinemag transformer's datasheet.
If anyone has more info about the lack of negative part of the signal and how to solve the problem, my ears are wide opened.
Thks
A.
It's a Neve clone with cheap parts and SMD components?
For a company that charges huge sums of money for mods in other brands pieces of gear, without ever providing proof of improvements, seems that they're products are the ones that should be modded.
Hi Astuck,
I'm sorry to hear about your experience with BLA.
Regarding the "trimmer mod", I don't think it will help you unless you having a biasing issue on Q11.
If you have one unit that works fine, try to do an A/B comparison between the working one to the faulty one and trace where the troubles are.
Good luck
Yes it's a clone with cheap parts and SMD components, but not a 1:1 clone, see the mic amp stage for example:
Here's the original Neve design:
And this is the same stage in the B173:
Not really a 1:1 clone, it seems like BLA took the main concept of the Neve design and made their cheaper version.
jensenmann
Well-known member
It seems BLA left out some of the negative feedback paths. That for sure will make it sound coloured...
It would be nice that a company offered to mod the B173 unit, a Tweakhead Max High whatever name Mod, for the same price Black Lion asks for modding perfectly working piece of gear....
It’s a bit sarcastic that people pay high amounts to black lion to mod their gear, when black lion is not even able to do a simple cloned Mic preamp
It’s a bit sarcastic that people pay high amounts to black lion to mod their gear, when black lion is not even able to do a simple cloned Mic preamp
This.
Can you describe "too noisy"?
I made a test with my B173, I've used quite high gain settings and the noise floor is around -64db.
This is the gain settings I've used:
Here's the file I've recorded
It would be interesting to compare it to your B173 with the same settings.
Hi @smilan,
I own a B173 I bought 10 years ago. I've never used it a lot but I recently had the opportunity to use it a bit more and (when it works) I quiet like it. I read your first post on these thread where you're talking about the negative half of the sinewave and I have the same problem. I'm not enough confident to mod audio devices on my own but what could I ask to somebody who does to solve this asymetrical sinewave problem ?
Did you finally add a fixed resistor to solve the problem ? If you did could you tell me which one and where did you placed it ? (I've download your technical scheme you posted).
Is there some other modifications you could advise me to improve this device ? Yes, It's not a neve but it's really handy tool though.
Thank you
I own a B173 I bought 10 years ago. I've never used it a lot but I recently had the opportunity to use it a bit more and (when it works) I quiet like it. I read your first post on these thread where you're talking about the negative half of the sinewave and I have the same problem. I'm not enough confident to mod audio devices on my own but what could I ask to somebody who does to solve this asymetrical sinewave problem ?
Did you finally add a fixed resistor to solve the problem ? If you did could you tell me which one and where did you placed it ? (I've download your technical scheme you posted).
Is there some other modifications you could advise me to improve this device ? Yes, It's not a neve but it's really handy tool though.
Thank you
