Any advice for parts to use in a Hairball 1176 Rev A?

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Deadly Mix

Audio-engineer
Joined
Sep 27, 2021
Messages
77
Location
Detroit
I'm about to begin building a Hairball 1176 Rev A (blue-stripe). I'm looking to get the most accurate to the original I can make. I've used a vintage Urei awhile back and looking to recapture that magic.
Any advice?
 
..given the huge variations even in original units, I wouldn't worry about "most accurate" when making a clone of it..

Build it, and see if it suits you - from there you can be more specific in alterations

/Jakob E.
 
Mind that Rev A uses specific Ed Anderson's output transformer that cannot be replaced by some other "regular" ones. And this transformer can only be bought from Hairball. But they don't have it in stock for a past year, more or less. Only if you buy complete kit you can get the transformer.
 
You can get the output transformer from Sowter and Cinemag can probably make it too.

The Sowter opt is almost twice the size of the Hairball one
 
..given the huge variations even in original units, I wouldn't worry about "most accurate" when making a clone of it..

Build it, and see if it suits you - from there you can be more specific in alterations

/Jakob E.
I understand that. I wanted to be more specific but it's obviously difficult to communicate.
I suppose I was just hoping for a "I swapped part A out for the brand X equivalence and it made the highs less harsh and more smooth, like a C800-G compared to a WA-8000" kind of response.
I'm looking for character/color of a typical 1176 "blue stripe". Clean enough to track through without regrets but not so clean that I might as well just use a Waves/UAD2 plugin.
Every Klark Teknik unit I've ever heard, in my opinion, was a complete waste of rack-space. They're so transparent you might as well just use a plugin. They probably would've been a big deal if they'd made them in the 1970s, when everything was "dirty" and transparency was hard to come by, but they're about as sterile as "ITB" with all of the "analog" buttons switched off. Basically, KT is the Fruity Loops of hardware... in my opinion.
At the same time, I like my Ampex 601 (modded into a 1 channel multi-tube mic pre) but it's far too colorful to use on every record. I've considered a couple of ways to run it in parallel with a cleaner signal so that I could dial in the amount in post.

Most of that may not be directly relevant but I'm hoping it tells you enough about me that you guys are more able to steer me in a good direction.

Oh, and this will be used in a professional studio, where it's the only non-original device, when it's finished.

I heard a Hairball Rev A during the lockdown that sounded just about perfect. It was the only 1176-style comp I'd ever heard sound exactly as I expect a blue stripe to sound. That unit is what lead to me decide to build one. I just don't know if it was modded in anyway and I no longer have the owner of it's phone number.
 
I should add that saving money isn't exactly the reason for building.
The last original I saw up for sale was listed at $20k. There are simply better things to buy for that kind of money.
If an original Urei transformer is a few hundred dollars or another option is simply not normally used because it's comparatively expensive, I'd rather pay for the more expensive part.
I can get a Purple MC77 for something like $1,700. If it costs a little more than that to swap out parts that affect the sound with original parts or even just higher end parts. I'm perfectly fine with and would actually prefer that.

Edit:
Which leads me to another question:
If I can find them, would original parts work in the Hairball or would too much have to be changed to use the originals?
 
There is nothing “magic” with audio gear. That word really has no meaning. People tend to get too hung up on some kind of voodoo, particularly when vintage parts are used. We have to stop following these trends and look at things in a more realistic view.

The 1176 has been discussed and built successfully by so many diyers. I think if at this point you come around here and question if it’s gonna be good as the original you shouldn’t be really considering diy. In my experience diy has never disappointed but again i don’t look for some kind of holy grail.
Build it and see if you will have a good surprise or a disappointment. If you don’t like it an 1176 has a good resell value anyway.

If you want a rev A the Hairball / mnats pcb is the only commercial option available as far as i’m aware. So i guess you should start with that and then if you feel the need you can upgrade to better quality transformers. The original utc O12 input can be sometimes found on ebay, to find an original opt is gonna be hard but i already suggested sowter and cinemag as an upgrade.
 
I understand that. I wanted to be more specific but it's obviously difficult to communicate.
I suppose I was just hoping for a "I swapped part A out for the brand X equivalence and it made the highs less harsh and more smooth, like a C800-G compared to a WA-8000" kind of response.
I'm looking for character/color of a typical 1176 "blue stripe". Clean enough to track through without regrets but not so clean that I might as well just use a Waves/UAD2 plugin.
Every Klark Teknik unit I've ever heard, in my opinion, was a complete waste of rack-space. They're so transparent you might as well just use a plugin. They probably would've been a big deal if they'd made them in the 1970s, when everything was "dirty" and transparency was hard to come by, but they're about as sterile as "ITB" with all of the "analog" buttons switched off. Basically, KT is the Fruity Loops of hardware... in my opinion.
At the same time, I like my Ampex 601 (modded into a 1 channel multi-tube mic pre) but it's far too colorful to use on every record. I've considered a couple of ways to run it in parallel with a cleaner signal so that I could dial in the amount in post.

Most of that may not be directly relevant but I'm hoping it tells you enough about me that you guys are more able to steer me in a good direction.

Oh, and this will be used in a professional studio, where it's the only non-original device, when it's finished.

I heard a Hairball Rev A during the lockdown that sounded just about perfect. It was the only 1176-style comp I'd ever heard sound exactly as I expect a blue stripe to sound. That unit is what lead to me decide to build one. I just don't know if it was modded in anyway and I no longer have the owner of it's phone number.
In my experience, my REV A has a lot of colour. Sounds absolutely amazing, but it can be a little too much depending on what you're going for. The noise floor can be a little too high for delicate tracks. There is the orange drop mod where you make a REV D which has a noticeably lower noise floor, and swap in the orange caps from the REV A to get the distortion of the REV A with the lower noise floor of the REV D. Not sure what the final product sounds like but is worth looking into if this is what you want.

https://www.hairballaudio.com/catalog/fet-rack/fetrack-orange-drop-mod
Hope this helps you on your journey in some way.
 
There is nothing “magic” with audio gear. That word really has no meaning. People tend to get too hung up on some kind of voodoo, particularly when vintage parts are used. We have to stop following these trends and look at things in a more realistic view.

The 1176 has been discussed and built successfully by so many diyers. I think if at this point you come around here and question if it’s gonna be good as the original you shouldn’t be really considering diy. In my experience diy has never disappointed but again i don’t look for some kind of holy grail.
Build it and see if you will have a good surprise or a disappointment. If you don’t like it an 1176 has a good resell value anyway.

If you want a rev A the Hairball / mnats pcb is the only commercial option available as far as i’m aware. So i guess you should start with that and then if you feel the need you can upgrade to better quality transformers. The original utc O12 input can be sometimes found on ebay, to find an original opt is gonna be hard but i already suggested sowter and cinemag as an upgrade.
lol. I think I'm trying to dance around words and over-explaining. I'll try to be simpler and more direct.

I want it to sound how a blue-stripe sounds in my head.
My expectation was formed using a couple real ones in other studios before and probably mildly tainted by now from using the UAD2 and Waves plugin emulations here and there.

I actually found both the input and output transformers, exactly as you mentioned, online for a few hundred bucks but they don't look like what's in my Hairball box here so I'm wondering:
Can I use them? Is there any difficult mod I would have to make that would require someone more familiar with building an 1176 than I to retro-fit or anything like that?
Someone also gave a link above for transistors. Am I asking for a world of trouble if I start making these mods?

It seems possible, or even probable, that the Hairball design has its own modifications to make it work without the original parts. If you swap out the motor in a new Camaro SS 5.8L V8 for an old 1970s Camaro SS 5.7L 350 V8 you're gonna have to make a lot more changes than just swapping blocks.
I assume this is similar in electronics. Like maybe I swap transformers for an original Urei and now something else has to be a different voltage or it doesn't connect the same way and making that mod changes impedance or voltage elsewhere and before you know it I have to make an entirely different PSU and the whole board needs to be redesigned just because I changed the transformers.
How accurate are my fears?
 
Thanks. Could you explain which parts to replace with this, is this the specific unit or just a brand suggestion, and what I should expect from the modification?
It's a hard to find part on the BOM, if your building a rev A you will need a few to select an matched pair.
 
I'm sitting at the bench and I humbly see that I've been getting ahead of myself a little.
Is anyone on right at this moment that can help me with something I'm stuck on?

I built the voltage select switch and am now on the next step. Meter PCB, Meter Selector, and Meter Resistors...
I don't know which resistors it means. It says "located with main components".
Is that the "Rev A components" box? I hope not because that's a few bags with a lot of resistors.
Or is that "Power Supply 1" box? That seems to make sense because there is a bag with 3 components. 2 of them look similar to the picture plus an orange one in the bag but what's making me doubt is the fact that the stripes aren't identical.
 
Well, I see from looking online that the stripes are apparently important so I'm gonna assume that, if I just go through every resistor here and find the ones that look exactly like the picture, those are the rights ones for R77 and R18.

If that's wrong, someone PLEASE happen to be on here and let me know right away.
If that's right, still let me know so I can feel confident that the pictures tell me everything I need to know to knock this out
 
best to measure each resistor with multimeter, and check with schematic, before soldering
Thanks. This is my first build (as I'm sure is obvious). Cory (our tech guy) usually does all this kind of stuff but I decided to do this assuming Cory was gonna stand behind me until I get the hang of it but Cory isn't here, Cory isn't answering his phone, and Cory isn't fire-able so Cory is a dick lol.

So- I dug into the Rev A box and found the bag that contained the range the resistors I was looking for should be in, according to the Rev A Components sheet. I then took them all out and held them under the light/glass 1 at a time and pulled out the ones that matched the color patterns (gray, red black, and orange blue black). The sheet says 4 of the type that R77 is and 1 of the type that the R18 is and that's how many I have of both types, so this appears to be correct.
 
Misplaced resistors / mixups with the values is pretty much the first stop on the “builder error troubleshooting tour,” so make sure to triple check those color codes, and as was suggested above, your best bet is to measure them with a multimeter before placing them. If you have a meter available, it’s VERY easy to do and one of the best low-effort-high-reward things that you can do.

Good luck!
 
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Reading your last comments I can only stress what I already told you on GS. Get the unit up and running with the stock components and see how you like it. Modifications or substitutions can make troubleshooting way more complicated and there's nothing more frustrating than a first build that ends up in the shelf because it doesn't work...
 
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I find the input pretty sensitive. Highly recommend doing the input mod on the website. Might even want to go higher than 100 ohm resistors.
 
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