1176 rev A : components test with sound samples

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evilcat

Well-known member
Joined
Jul 30, 2009
Messages
396
Location
France - Paris
Hi all !

Here are lot of samples I’ve done during the building process of my 2 Mnats’1176 rev A.
While I was reading the Rev A thread and schematics on JBL site, I noticed few differences that I wanted to test :

- caps : on the original Urei schematic C23 is tantalum, and some people choose C3 as tantalum too, instead of electrolytics.
- resistors : on the original R64=1.2k and R62=560R, then after few revisions R64=2.2k and R62=470R. There’s also a mod to avoid « pops » in All Buttons Mode where R78=link and R19=130k become R78=47k and R19=68k.
- last thing I wanted to try : using 3708 or 5088 as transistors.

Having 2 units makes it easy to do. I’ve done 4 versions of  1176 revA :

V1 : 3708 trans – C3 and C23 electrolytics – modified resistors
V2 : 3708 trans – C3 and C23 tantalums – original resistors
V3 : 5088 trans – C3 and C23 electrolytics – modified resistors
  V4 : 5088 trans – C3 and C23 tantalums – original resistors



With all these units, I played some samples : drums (kick+snare+overhead), vocal, electric gtr and acoustic gtr, and recorded them for all ratios : 4, 8, 12, 20 and All Buttons.
For drums and vocal I set the units to 6dB of compression, Attack@12 o’clock and Release@fast.
For electric and acoustic gtr I set the units to 3dB of compression, Attack@12 o’clock and Release@fast.

Things I have noticed :

- V2 and V4 : seems to be much more transparent, you can here less compression.
- Original resistors values are less « stable », at 20:1 it compress more without touching the settings.
- Modified resistors values work great to canceled the « pop » issue in All Buttons mod and give the same gain reduction for all ratios without touching the settings.
- 5088 trans are brighter and seem to have a slower attack time and a faster release time.

I prefer V1 and V3 because they have more character. I don’t want my 1176s to be transparent compressors, I want some « attitude » and that’s what V1 and V3 give me.
Then between V1 and V3, I choosed V3. Except for electric gtr, I prefer the brighter thing. It makes drums and ac gtr more precise and gives the vocal more presence. For electric gtr, V1 gives a fatter sound, but we can’t have everything !!!
To help me choosing between V1 and V3, I played all the V1 tracks, make a quick balance, matched V3 levels, and then flip one by one to V3. It created a more precise mix, and that’s what led me to choose V3.



So, here are the links to download the 24bits/44.1kHz files. One link for one instrument. For each instrument you have the 5 different ratios for each 1176 version plus the original sound, uncompressed :

Acoustc gtr : http://www.megaupload.com/?d=Q33BBVQL
Drums : http://www.megaupload.com/?d=05MVGOWP
Electric gtr : http://www.megaupload.com/?d=NQAB73KO
Vocal : http://www.megaupload.com/?d=2VKUW69A

Each file is about 140 Mo. It’s big and take a long time to download but I think it worth it to everyone who wants to build this unit.

I hope that you’ll find this interesting and don’t forget that it’s all a matter of taste !

Ben A.
 
No problem ! If it's usefull for you guys, then I'm happy  ;D
I really am a newbie but I wanted to bring some contributions to this wonderful forum. I hope that futur builders will take advantage of this research.

Ben
 
Brilliant, revelatory, thanks a million for sharing :)

'V4 drums all' -- uhh.
V3  8)
V4 also not bad, yeah, sounds more transparent...

I quickly tried to find info regarding the tantalums, but couldn't; threads are long: Is it the tantalums that make V2 and V4 sound more transparent or the original resistors that do that? I assume that V4 with 'tantalums' and 'modified resistors' would be good for transparent treatment, somewhat closer to original material... Anyone built one like that?
 
hello
I Have  built two REV A with  tantalum caps and resistance mod ...
sounds wonderful!!!
I also built two 3 x D REV
2 with the metal film resistors and Wima caps
1 with carbon composition resistors and orange  drop caps...
I prefer the latter, it sounds softer and deeper
I hope to be helpful...
Ciao
 
Oh yeah ilfungo, you make me think of something I forgot to mention : my units use carbon comp resistors in the preamp and line amp sections, 1% metal film in the PSU and Meter sections, and carbon film in the GR section and ratio board.


Script said:
Brilliant, revelatory, thanks a million for sharing :)

'V4 drums all' -- uhh.
V3  8)
V4 also not bad, yeah, sounds more transparent...

I quickly tried to find info regarding the tantalums, but couldn't; threads are long: Is it the tantalums that make V2 and V4 sound more transparent or the original resistors that do that? I assume that V4 with 'tantalums' and 'modified resistors' would be good for transparent treatment, somewhat closer to original material... Anyone built one like that?

You're welcome Script. With V4 and V2 the "all" position is just awful, if you want to use it you HAVE to do the mod !
Regarding the tantalums, I honestly don't know. I could have push further the research by changing just the caps or the resistors but I don't have the courage  :p You will have to try that for us  ;D.
You won't find any information on that in the thread, I read it many times. What give me the idea of using tantalum for C3 are these build pictures of Stagefright13 :

http://www.groupdiy.com/index.php?topic=29981.80

Anyway, I'm already surprised that changing so few components have an effect on the sound (even if that's what I hoped !) so I guess that it's the tantalums AND the original resistors who achieved that... Don't know, just a thought.

Ben

 
Hi again !

A friend of mine took my drums sample to put it thru a modern Universal Audio 1176, with the same settings of course, and  for the 4 and 8 ratios. Now you can compare our rev A version with a modern one ! And it reassured me, as I have never heard a real 1176 (only in plug ins !!!) : you can hear it’s different of course but we’re definetly in the same family. Compared to the V3 version I choosed for my builts, the modern one seems a little more open sounding, feels a little less compressed. 
As it’s not the same revision it’s not a surprise but still, it’s really close character-wise !
Here is the link to download the 24bits/44.1kHz files of the UA version :

http://www.megaupload.com/?d=AD2XU4G8

Ben A.
 
evilcat said:
- resistors : on the original R64=1.2k and R62=560R, then after few revisions R64=2.2k and R62=470R. There’s also a mod to avoid « pops » in All Buttons Mod where R78=link and R19=130k become R78=47k and R19=68k.
-
Ben A.

Interesting thread, thanks.  I don't have a chance to check schems for the moment, do you know if these resistors are the same used in Rev D?  If it's sidechain, may be the same...?
 
R62 and R64 are the same in rev A and rev D, control Ratios.
On Mnats - rev A : R62=470 and R64=1k2
                - rev D : R62=560 and R64=1k5
What I choose R62=470 and R64=2k2.
 
Thanks!  Are these ratio resistors being changed only to avoid pops in the all-buttons/Slam mod/mode? 

A clarification: You called it the all-buttons mod (no "e" - not "mode" - not a typo?).  This is different from the all-buttons in / Slam mode?

...I haven't heard about an all-buttons mod.
 
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