The No.1 Website for Pro Audio
I like my GML 8200 - BUT...
Old 7th February 2010
  #1
Gear Addict
 

Verified Member
I like my GML 8200 - BUT...

... mine is a pain in the arse.

Since I don't justify the extra thousands of pounds in stepped pots, all my mastering units are "standard version". Instead, what I do is a run an oscillator and sweep around to level out any disparities between L and R looking at the meters.

My trusty Massive Passive is 9 out of 10 times always matching in balance (meaning that what you dial is pretty much what you get). My IBIS is always a little out, mainly due to human error as the pots are small and light...

... the GML however is always WAY out! If I perfectly dial a boost in a frequency, when run the oscillator through it (it check lows, low mids, mids, upper mids and top) 10 out of 10 times the balance of L and R is different by a significant audible amount (we're talking 1 sometimes 2dB here)... I'm suspecting the left channel is slightly louder overall.

I was wondering if anyone had this problem or if anyone knows how to calibrate these beasts!

Thanks to all in advance.
Old 7th February 2010
  #2
Gear Nut
 

Quote:
Originally Posted by Gomez View Post
... mine is a pain in the arse.

Since I don't justify the extra thousands of pounds in stepped pots, all my mastering units are "standard version". Instead, what I do is a run an oscillator and sweep around to level out any disparities between L and R looking at the meters.

My trusty Massive Passive is 9 out of 10 times always matching in balance (meaning that what you dial is pretty much what you get). My IBIS is always a little out, mainly due to human error as the pots are small and light...

... the GML however is always WAY out! If I perfectly dial a boost in a frequency, when run the oscillator through it (it check lows, low mids, mids, upper mids and top) 10 out of 10 times the balance of L and R is different by a significant audible amount (we're talking 1 sometimes 2dB here)... I'm suspecting the left channel is slightly louder overall.

I was wondering if anyone had this problem or if anyone knows how to calibrate these beasts!

Thanks to all in advance.
Can you hear any imbalance? Maybe it does not matter so much after all?


SB
Old 7th February 2010
  #3
Gear Addict
 

Verified Member
Hey SB

I'm from the "ear" school - I don't use analyzers, just the Dynamic Range meter. Yes, the difference can be VERY noticeable (audibly). If I boost a shelf starting at say 2.5K the left side will be noticeably louder...
Old 7th February 2010
  #4
Gear Nut
 

Quote:
Originally Posted by Gomez View Post
Hey SB

I'm from the "ear" school - I don't use analyzers, just the Dynamic Range meter. Yes, the difference can be VERY noticeable (audibly). If I boost a shelf starting at say 2.5K the left side will be noticeably louder...
Ok - glad you are from the same school! I just remember from my old (old) day of some mixing that no processor we had had switches and so the engineer adjusted by sight and then ear. It is a problem for you I agree I just thought maybe not so much on your practice as you can hear it?


SB
Old 7th February 2010
  #5
Lives for gear
 
Paul Gold's Avatar
 

Verified Member
8 Reviews written
You could change the gain range set resistors for a smaller range. You probably don't need +/- 12dB.
Old 7th February 2010
  #6
Lives for gear
 
surflounge's Avatar
is there a buss EQ with one knob for both channels?
Old 7th February 2010
  #7
Lives for gear
 
matucha's Avatar
 

Verified Member
1 Review written
gyraf g14 for ex is stereo only
Old 7th February 2010
  #8
Lives for gear
 
Cellotron's Avatar
 

Verified Member
3 Reviews written
Quote:
Originally Posted by Paul Gold View Post
You could change the gain range set resistors for a smaller range. You probably don't need +/- 12dB.
Which is what I had done for my Sontec MEP250EX (which is similar to the GML 8200). A simple addition of a couple resistors per band changed the range from +/- 12dB down to +/-6dB so that settings and side matching is a lot less "tweaky". Not perfect - but way better - and with the advantage that 1/2dB gain steps are now available.

Best regards,
Steve Berson
Old 7th February 2010
  #9
Lives for gear
 
24-96 Mastering's Avatar
Quote:
Originally Posted by Cellotron View Post
Which is what I had done for my Sontec MEP250EX (which is similar to the GML 8200). A simple addition of a couple resistors per band changed the range from +/- 12dB down to +/-6dB so that settings and side matching is a lot less "tweaky". Not perfect - but way better - and with the advantage that 1/2dB gain steps are now available.

Best regards,
Steve Berson
Did the same with my Sontec 250C. Using it is much more fun now.

I imagine if you asked Massenburg / Manley, they'd happily instruct you on how to mod the GML. Or maybe they can mod it for you, if you prefer.
Old 8th February 2010
  #10
Gear Addict
 

Verified Member
Quote:
Originally Posted by 24-96 Mastering View Post
Did the same with my Sontec 250C. Using it is much more fun now.

I imagine if you asked Massenburg / Manley, they'd happily instruct you on how to mod the GML. Or maybe they can mod it for you, if you prefer.

Thank you all for the input, much appreciated.

The 6dB mod sounds like a great idea, but besides that, i would have thought these kind of units would be very precise and both channels calibrated to near perfection. Can the unit be calibrated anyway?
Old 8th February 2010
  #11
Engagement Manager
 
Sniperschool's Avatar
 

Verified Member
hey G
happy new year to you by the way bro
they can be calibrated but i always thought they had to go back to the 'GML/Manley mothership' to do it
there was another thread recently asking about it actually
let me know if you find out differently
you preferring the 8200 to the IBIS?
thumbsup
Old 8th February 2010
  #12
Lives for gear
 
MASSIVE Master's Avatar
 

Verified Member
Quote:
Originally Posted by Gomez View Post
Hey SB

I'm from the "ear" school - I don't use analyzers, just the Dynamic Range meter. Yes, the difference can be VERY noticeable (audibly). If I boost a shelf starting at say 2.5K the left side will be noticeably louder...
Went through three of them before I finally just gave up for the same reason. Was told they were "within spec" (which I found to be the most ridiculous thing I had ever heard from a company with such a reputation).

Really liked the sound of the unit though. But "feathering" one knob and "throwing around" the other (and it was different from left/right - cut/boost of course) got really old really fast...
Old 8th February 2010
  #13
Lives for gear
 
Adam Dempsey's Avatar
 

Verified Member
Quote:
Originally Posted by Gomez View Post
Thank you all for the input, much appreciated.

The 6dB mod sounds like a great idea, but besides that, i would have thought these kind of units would be very precise and both channels calibrated to near perfection.
I've never known the stock 8200 to be channel accurate or recall accurate (it's +/- 15dB), and for mastering is why GML have the 9500 model.

Quote:
Originally Posted by surflounge
is there a buss EQ with one knob for both channels?
Sontec MES462 can't be beat, IME.
Old 8th February 2010
  #14
Gear Addict
 
turtlerock's Avatar
 

Verified Member
me thinks you are perzactley right adam
on both counts
Old 8th February 2010
  #15
Lives for gear
 
Waltz Mastering's Avatar
 

Verified Member
1 Review written
Quote:
Originally Posted by Adam Dempsey View Post
I've never known the stock 8200 to be channel accurate or recall accurate (it's +/- 15dB), and for mastering is why GML have the 9500 model.
+1 - The 8200 can be a bit wiggley in the tooth when it comes to L/R balance, I notice it a bit more in the mid band. The 6 dB mod seems like a good idea. I can't remember ever needing any more than a few in an extreme circumstance anyway. Going to the 9500 is a big jump cash wise ($9G).
Old 8th February 2010
  #16
Lives for gear
 

Quote:
Originally Posted by Gomez View Post
I was wondering if anyone had this problem
Yes I did. This is sick.
Old 8th February 2010
  #17
Lives for gear
 
exwel's Avatar
Quote:
Originally Posted by sniperschool View Post
hey G
happy new year to you by the way bro
they can be calibrated but i always thought they had to go back to the 'GML/Manley 'mothership' to do it
there was another thread recently asking about it actually
let me know if you find out differently
you preferring the 8200 to the IBIS?
still got to get those cartecs up to you to have a listen to
thumbsup

That was me.
6db mod sounds nice.
Old 8th February 2010
  #18
Gear Addict
 

Verified Member
Quote:
Originally Posted by exwel View Post
That was me.
6db mod sounds nice.

Thank you all for the info.

Happy new year to you Sniperschool!
I'm liking the GML, but it is quite different to the IBIS. I love the bottom end of the GML and it's really quite amazing at notching out stuff. The IBIS is getting only used for the top, which I really like. The bottom end can work on some stuff, not sure about the mids for mastering (taking into account that 70% percent of the stuff I master has distorted guitars) - th IBIS doesn't seem to get on with this.

I'm sure the 9500 is great, but I just don't have that money. I'm slightly shocked about this as the 8200 has been widely used for mix buss throughout the years.. I guess I'll call GML and see what they say. Slightly disappointed.
Old 8th February 2010
  #19
Gear Head
 

IMHO the 8200 sounds great on pretty much anything, but I agree that the precision of the pots isn't the best. There are some ways around this that I often use.

One way to balance the channels is to sum the source to mono, while listening to the difference signal post EQ and tweak until it nulls.

Or you can distribute the error differently by having the EQ in an MS-chain. Instead of L/R imbalance you'll get changes in the stereo width, which often is less noticeable in a pop song. The balance trick mentioned above also gets easier in MS; mute one channel in the source while listening to the same channel soloed post chain.

The mod for getting +-6dB sounds really interesting!
Old 8th February 2010
  #20
Lives for gear
Quote:
Originally Posted by Gomez View Post
... the GML however is always WAY out!
Maybe that's why I ended up liking it so much on the mix bus! It must be a bear to master with though.

Mychal
Old 8th February 2010
  #21
Lives for gear
 
edva's Avatar
I've noticed this with a lot of analogue gear. Makes me feel better about mastering ITB anyway.
Old 9th February 2010
  #22
Lives for gear
 
Jerry Tubb's Avatar
 

Verified Member
Quote:
Originally Posted by Gomez View Post
I'm from the "ear" school - I don't use analyzers
Ban Him!

JT
Old 9th February 2010
  #23
Gear Addict
 
streaky's Avatar
 

Quote:
Originally Posted by Jerry Tubb View Post
Ban Him!

JT
lol...

My 8200 is way off but using it in M/S does help, but I'm gonna get that mod done sounds perfect...
Old 15th February 2010
  #24
Gear Addict
 
streaky's Avatar
 

I've asked GML about the mod in db this was the reply :

We don't offer any gain modifications or production variations for the 8200; however, nearly anything is possible. A mod of this sort would entail sourcing a highly customized control in addition to a gain-set buildout. The rework itself could be relatively trivial and the calculation of values fairly straightforward, but the headache and cost is in the control. For reference: in production quantities, the existing control costs $50.

That being said, the production control could also be "slugged" -- but this will significantly (and non-linearly) alter the cut/boost taper. That would completely change the "feel" and function of this control ... not something we would recommend, but it might be acceptable for a specific installation / application.

Best regards,
Jeff
=====
Jeffrey Warren
GML, LLC.
Nashville, TN USA
George Massenburg Labs
Old 15th February 2010
  #25
Lives for gear
 
Paul Gold's Avatar
 

Verified Member
8 Reviews written
It's a center tapped pot which are hard to find in small quantities. In the Sontec the values of the pot and gain set resistors allow for easy modification. You could have a tech look at it. There might be an easier way.
Old 16th February 2010
  #26
Gear Addict
 

Verified Member
Quote:
Originally Posted by streaky View Post
I've asked GML about the mod in db this was the reply :

We don't offer any gain modifications or production variations for the 8200; however, nearly anything is possible. A mod of this sort would entail sourcing a highly customized control in addition to a gain-set buildout. The rework itself could be relatively trivial and the calculation of values fairly straightforward, but the headache and cost is in the control. For reference: in production quantities, the existing control costs $50.

That being said, the production control could also be "slugged" -- but this will significantly (and non-linearly) alter the cut/boost taper. That would completely change the "feel" and function of this control ... not something we would recommend, but it might be acceptable for a specific installation / application.

Best regards,
Jeff
=====
Jeffrey Warren
GML, LLC.
Nashville, TN USA
George Massenburg Labs
Thanks for the info Streaky

Hmmm... OK I can live with +/- 15, but I'd really like it to be at least a bit accurate - seriously, it's always WAY out.

@ MASSIVE: Did they actually did anything to your units? or they just tested them and said they were fine? if that's the case, then they should get some decent measuring equipment!

@ edva: My other 2 eq's are pretty good actually (massive passive and IBIS), and the reward is sweeter, or at least it is to my ears.

I'm considering sending the 8200 back.... but what to replace it with?
Old 16th February 2010
  #27
Lives for gear
 
MASSIVE Master's Avatar
 

Verified Member
Quote:
Originally Posted by Gomez View Post
@ MASSIVE: Did they actually did anything to your units? or they just tested them and said they were fine? if that's the case, then they should get some decent measuring equipment!
They tested it - Came up with the same results the tech I originally sent it to came up with and said it was within spec.

I think that was the second unit... I tried another and came up with pretty much the same thing, so I was pretty much done with them at that point.
Old 16th February 2010
  #28
Gear Addict
 

Verified Member
Quote:
Originally Posted by MASSIVE Master View Post
They tested it - Came up with the same results the tech I originally sent it to came up with and said it was within spec..
That is just disappointing! tutt GML

I'm going to contact them and see what they say. Thanks John.
Old 17th February 2010
  #29
Lives for gear
 

I've had similar problems with L-R drift in my 8900 compressor. It went back to GML, got $500 worth of work done to it, and they said that it was all within spec. Not only am I hearing this thing change, but it's totally noticable on the meters, as well.

Chris Garges
Charlotte, NC
Old 17th February 2010
  #30
Gear Head
 

Is this a problem with every 8200, or is it hit and miss? In other words, does anybody not have this issue with these things. I've been thinking about trying one out, but now I dunno...
๐Ÿ“ Reply

Similar Threads

Thread / Thread Starter Replies / Views Last Post
replies: 51 views: 6924
Avatar for edcampos
edcampos 9th November 2008
replies: 333 views: 67702
Avatar for JimmyBoyZ
JimmyBoyZ 15th February 2020
replies: 15929 views: 1484728
Avatar for Ragan
Ragan 11th January 2019
replies: 25569 views: 2494751
Avatar for Ranformer
Ranformer 7 minutes ago
Post Reply

Welcome to the Gearslutz Pro Audio Community!

Registration benefits include:
  • The ability to reply to and create new discussions
  • Access to members-only giveaways & competitions
  • Interact with VIP industry experts in our guest Q&As
  • Access to members-only sub forum discussions
  • Access to members-only Chat Room
  • Get INSTANT ACCESS to the world's best private pro audio Classifieds for only USD $20/year
  • Promote your eBay auctions and Reverb.com listings for free
  • Remove this message!
You need an account to post a reply. Create a username and password below and an account will be created and your post entered.


 
 
Slide to join now Processing…
๐Ÿ–จ๏ธ Show Printable Version
โœ‰๏ธ Email this Page
๐Ÿ” Search thread
๐ŸŽ™๏ธ View mentioned gear
Forum Jump
Forum Jump