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ADA8000 - What opamps for upgrading?
Old 16th October 2011
  #1
ADA8000 - What opamps for upgrading?

ADA8000 - What opamps would be recommended for this?

I'd like to use TL1359 op amps (digikey seems to be out) for my mod - replacing the stock 073's.

14 pin surface mount package.

I wonder what the BLA mod uses for opamps?
Old 16th October 2011
  #2
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S2udio's Avatar
 

ADA8000 .... A Search will bring up endless threads on the subject..
But imho your wasting your time.The psu needs attention as well....
Oh i see you already know that !
Why start another thread ?
Good luck anyways.
Old 16th October 2011 | Show parent
  #3
There is no thread on the Opamps.

What would be some highend "drop in" replacements?
Old 16th October 2011
  #4
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esaias's Avatar
ADA8000 mods would need its own wikpedia page, there are loads of discussion about it in here and on other forums but the actual useful information is actually difficult (-ish, atleast) to find. And yes, I'm too going to get ADA8000 soon and mod it...

-tomi
Old 16th October 2011 | Show parent
  #5
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S2udio's Avatar
 

Quote:
Originally Posted by piano View Post
There is no thread on the Opamps.

What would be some highend "drop in" replacements?
There are .Did i say here ?
Join DIY @Prodigy pro.
Old 16th October 2011 | Show parent
  #6
Quote:
Originally Posted by esaias View Post
ADA8000 mods would need its own wikpedia page, there are loads of discussion about it in here and on other forums but the actual useful information is actually difficult (-ish, atleast) to find. And yes, I'm too going to get ADA8000 soon and mod it...

-tomi
Ha! You are so right. I've seen mods from Summing mixers, to opamp upgrades and even mods to become a baseball. It does need it's own wiki page!
Old 16th October 2011 | Show parent
  #7
Quote:
Originally Posted by S2udio View Post
There are .Did i say here ?
Join DIY @Prodigy pro.
You mean GroupDIY - Index - it changed site names recently. Sure, I do belong there but I have found nothing much of use about the opamps to use for the ADA800.

If you can find something - let us know here. Thanks!!!

The best thing I have found is ADA8000 mods

The web page maker is happiest with LT1359's
Old 16th October 2011 | Show parent
  #8
Quote:
Originally Posted by Jim Williams View Post
LT1359CS are SOIC 16 pins. Try a BB OPA1644 or National LME49740MA.
Thanks Jim Williams! You are very helpful to a lot of us!

At Digikey - the only in stock 14 pin LT1359's are through hole type (LT1359CN#PBF). See Here.
A guy HERE used LT1359's - clearly surface mount 14 pin - But I can not find them in stock anywhere!

Can it really be done using LT1359s?

Below is a pic from his site with an LT1359IS14.
Attached Thumbnails
ADA8000 - What opamps for upgrading?-ada8000pic3.jpg  
Old 19th October 2011 | Show parent
  #9
BLA uses 2134 and 4134 opamps. The above link to the guy in Brazil who does his mod uses 1359's on the inputs and 4134's on the outputs.

I am doing the mod, I LOVE what BLA does!
Old 19th October 2011 | Show parent
  #10
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Kris Bang Boom's Avatar
Quote:
Originally Posted by piano View Post
BLA uses 2134 and 4134 opamps. The above link to the guy in Brazil who does his mod uses 1359's on the inputs and 4134's on the outputs.

I am doing the mod, I LOVE what BLA does!
Are the 2134 in and the 4134 out and what else do they do
thanks
Old 19th October 2011 | Show parent
  #11
AD8512A for TL 072, AD8513 for TL 074.


LT 1358 for TL 072 & LT 1359 for TL 074.
Old 19th October 2011 | Show parent
  #12
You can switch TL072 with OPA2134 pretty safely and and sometimes you can swap NE5532 with TL074 in Low input impednace Opamp configureation....

It totally depends on the circuit....
Old 19th October 2011 | Show parent
  #13
Quote:
Originally Posted by Kris Bang Boom View Post
Are the 2134 in and the 4134 out and what else do they do
thanks
According to BLA:

"For this modification we not only perform the op-amp upgrade, but we replace vital analog signal caps with capacitors of dramatically higher quality, and we use premium audio electrolytics on both inputs and outputs. We also perform converter decoupling using the same techniques found in our Alesis AI-3 Premium upgrade, our acclaimed Signature Series modifications, and in our widely-praised FM192. After this upgrade, the ADA8000 will have a much wider stereo field, a smoother & more defined bass, and sweeter-sounding highs. We are certain that this upgrade will easily bring you into the range of the Apogee Rosetta series, if not surpass it altogether."

There you go.

also found this on GS from a member getting this from BLA:


"We are going to start offering the Apogee Ensemble modification for $575 + return shipping. We will be addressing the converters as well as the analog pathways in and out of the unit. We highly recommend using our external Micro Clock mk2 in conjunction with the Ensemble as it has yielded great results in our shop.
Old 19th October 2011 | Show parent
  #14
Quote:
Originally Posted by Kris Bang Boom View Post
Are the 2134 in and the 4134 out and what else do they do
thanks
Those are long in the tooth parts with a spitty top end, not flattering for digital. BB has newer, better choices out. The OPA 1641/2/4 are much lower noise and THD with 1/2 the power draw. If you can deal with bipolar inputs instead of JFETS, the OPA1611/12 are good as are the National LME49710/49720/49740.
Old 21st October 2011 | Show parent
  #15
I talked to Linear Tech today.

They thought that the LT1469 (Dual only) and their older LT1359 (Quad) would be great for this.
Old 21st October 2011
  #16
Pics of my new 2011 unit.
Attached Thumbnails
ADA8000 - What opamps for upgrading?-img_2296.jpg   ADA8000 - What opamps for upgrading?-img_2297.jpg   ADA8000 - What opamps for upgrading?-ada8000-2011.jpg  
Old 21st October 2011 | Show parent
  #17
So inside my 2011 ADA8000 are:

(4) 074C EZ87043 Quad Op Amps
(4) 072C eZ043 Dual Op Amps

The Texas Instruments PDF on these Op Amps is http://www.ti.com/lit/ds/symlink/tl071.pdf
Old 21st October 2011 | Show parent
  #18
Thank you Jim.

At the price of opamps (which will fit here), it is logical to go with the best that will work with the circuit.

Based on what have here - what do you believe is the best (I will stay away from the 2134 and 4134)?

Ever tried the 1359?
Old 21st October 2011 | Show parent
  #19
More pics - the outside and the power circuit.
Attached Thumbnails
ADA8000 - What opamps for upgrading?-img_2299.jpg   ADA8000 - What opamps for upgrading?-img_2300.jpg  
Old 21st October 2011 | Show parent
  #20
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Kris Bang Boom's Avatar
Are the ADA8000 opamps soldered in or can you pull them out?
Thanks
KBB
Old 22nd October 2011 | Show parent
  #21
Quote:
Originally Posted by Kris Bang Boom View Post
Are the ADA8000 opamps soldered in or can you pull them out?
Thanks
KBB
They are surface mount (soldered on) - about 1/4 the size (as in very small) of the through hole type you can just pull out. I've been doing several DIY projects for about a solid year now with my best bud who is an MIT grad. (which is how I will be able to double check on the op amps recommended here.)

You can do surface mount see HERE but I do not recommend it for beginners without experienced tutored guidance like I had. It could be easy to rip a pad off - which is a pain in the ass to fix. Personally, I do not feel ready for it which is why I am having BLA do the work for me.
Old 22nd October 2011 | Show parent
  #22
Quote:
Originally Posted by Jim Williams View Post
I have them in my HD24XR.

Best quads are: LT1359, LME49740 and AD8513, pick your poison.

Best duals are: LME49720, AD8512, OPA1612, ADA4898-2. For high current drive, the LM6172 is also very good.
Spectacular Jim Willaims! Thankyou. VERY VERY helpful.

I assume I will have to check to make sure all of these will work in the circuit. There is probably no way you know what works and what does not, huh?
Old 22nd October 2011 | Show parent
  #23
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Kris Bang Boom's Avatar
Quote:
Originally Posted by piano View Post
They are surface mount (soldered on) - about 1/4 the size (as in very small) of the through hole type you can just pull out. I've been doing several DIY projects for about a solid year now with my best bud who is an MIT grad. (which is how I will be able to double check on the op amps recommended here.)

You can do surface mount see HERE but I do not recommend it for beginners without experienced tutored guidance like I had. It could be easy to rip a pad off - which is a pain in the ass to fix. Personally, I do not feel ready for it which is why I am having BLA do the work for me.
Thanks and thanks for the link,
I have watched a view other videos on this and it does look hard,
might try to find a local tech that is good at the soldering the chips and do the rest here.
KBB
Old 22nd October 2011 | Show parent
  #24
From reading the threads I think there are now at least FOUR versions. BLA can only do their premium mod to ones made after Jan 2010.

Before there was a version (G and the one I have is H - Made Jan 2011) with the board labeled pcb*516080*REVG/02 --- See HERE for labeling of REV G


Previous versions had power supply problems due to the transformer feeding too much power to the Regulators. Resulting in regulators burning out, a bad ceramic cap near the rectifier (on the first version, the second apparently made it a film cap) frying and transformer thermal fuse problems. Some report that the bad cap or regulator causes the thermal fuse to blow, like a cascading problem.

So reporting on the new unit - Rev H, it has Cirrus converter. I am not finding hot regulators with out heat sinking. The ceramic cap is now film. But the odd thing is that main board buffer formerly made up of a quad opamp split between adjacent channels, is a single chip (8 pads) 072c (TLO72) between each pair of channels, and I cannot figure out the buffer works (are they inverting?)

Here are the Chips I can read on the main board

Cirrus Logic CS4270-CZZ
ST 074C ( TL074 near the output jack)
ST 339 ( VU meter LM339)
ST 072C ( TL072 positioned between molex pairs where the old 4 way op oamp buffer was)
Wavefront AL1402G (m)
Wavefront AL1401AG

Board is marked P 0187 pcb 929100 Rev H/02

I did look at the Cirrus CS4270 spec and notice that while the wavefront 1101 had a differential inputs, this has single ended inputs. So maybe they don't need to carry a balanced signal on the board and that is why they don't need the second half of that buffer? How would one buffer the Cirrus chip for single ended use? Could I still run a balanced line level signal with appropriate resistors directly to it's non-inverted and inverted inputs?

I did some testing
I could measure hum on the preamps with the gain up some and using digital gain in the DAW.

I measured higher hum (60Hz, 120HZ, and 280ish Hz) on the channels. Worst on channel 8, best on channel 1. I found by adding MU Metal shielding to the back of the front panel (there is a shield there now over channels 8 7 and 6, put probably steel, and I just taped MU Metal over it, but filled in the gaps, extended it some, and added smaller shield further down the front panel. Adding the shield quieted down the channels some.

Note to anyone that has one of these ADA-8000, the front panel is not well shieled, and is very sensitive to the rotation of the transformer.

I loosend the transformer and rotated it while listening to a channel. This makes a HUGE difference, and between that and Shielding I could get channel 8 really quiet (like #1). But it is a tradeoff because 4 and 5 were then the noisiest, and lowering them raises 6, 7, 8 somewhat.

I tried shielding the transformer, unsuccessfully, not much room, and I was worried about creating a shorted loop or heat problems? (how much of a toroid can I contain in shield material without worrying about this "shorted loop" issue? Anybody know?)

Front panel shielding made a big difference and the rotation did even more (although the rotation can fix some bad hum, it also moves hum to other channels) (I got 2 or 3 db lower hum overall off a mix of 8 channels, when I had the hum cranked up to -9 db I got it down to -12 by rotation and shielding. Hum on channel 8 was reduced more dramatically.


I am not finding heating problems with regulators.
Old 23rd October 2011 | Show parent
  #25
Does anyone have a schematic of Rev H? You can PM me.

This is what I found HERE

Labeling of the Rev G (not the latest Rev H) HERE


According to the schematic of the gyraf, you could us a bi-polar instead of a JFET opamp. A LT1359 (a Bi-polar) is used in the in Rev. G mod.

Behringer sent me this in response to my schematics request (Reasonable, as companies have the duty to protect their work)
"Behringer only releases schematic diagrams to our Authorized Service Centers.

This is partially due to the need to keep proprietary intellectual property protected, but also because giving a schematic to a customer implies that we are recommending the customer perform their own repair. This is contradictory to company policy, as we only recommend our Authorized Service Centers to perform repairs on Behringer products.

Adhering to this policy guarantees that all repair work is carried out to factory specifications, and that all warranties are maintained. It also ensures quality work by factory-authorized technicians - and it simply keeps us out of liability issues. We apologize for any inconvenience."
Old 28th October 2011
  #26
YES! In the rev G you can use bi polar op amps! LT1359 !!!
Old 31st October 2011 | Show parent
  #27
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Hi
You can completely enclose a toroid with metal as long as you do not have a metallic connection through the centre of the core. So if it has a central bolt to fasten it in place, you must not connect the top of the bolt with the bottom using any form of conductor.
Full enclosure may cause it to overheat if it is required to deliver much power which is probably not the case here.
Matt S
Old 31st October 2011 | Show parent
  #28
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S2udio's Avatar
 

Quote:
Originally Posted by piano View Post
Does anyone have a schematic of Rev H?
Do you have any full schematics ?......I may have rev f in the archives.
Or just sign in to groupdiy
You can always update and note any changes as you find them.

Quote:
Originally Posted by piano View Post
I measured higher hum (60Hz, 120HZ, and 280ish Hz) on the channels. Worst on channel 8, best on channel 1. I found by adding MU Metal shielding to the back of the front panel (there is a shield there now over channels 8 7 and 6, put probably steel, and I just taped MU Metal over it, but filled in the gaps, extended it some, and added smaller shield further down the front panel. Adding the shield quieted down the channels some.
Hmmmmm ......Something else going on there....never seen that HUM problem on the ones
Ive brought back to life,Or at least the ones that worked correctly after repair.
Even with the lid off.

Quote:
Originally Posted by piano View Post
Note to anyone that has one of these ADA-8000, the front panel is not well shieled, and is very sensitive to the rotation of the transformer.
Are you sure its not PSU noise......scope it
Old 18th August 2012 | Show parent
  #29
Quote:
Originally Posted by Kris Bang Boom View Post
Are the 2134 in and the 4134 out and what else do they do
thanks
Yes, the 2134 are duals and are the IN's. You need FOUR of these.

The 4134 are quads and are OUT's. You need FOUR of these.
Old 18th August 2012
  #30
I am going to use these to swap out chips easily.

This converts a solder only input on the board to a pull-able chip.

The following are available in pull-able chip form (DIP)

STOCK ADA8000 TL 074 (Quad) TL 072 Total harmonic distortion 0.01% BANDWIDTH: 3MHzNOISE: 15nV/Hz, 13V/Β΅s Slew Rate - COST About $1.05 ea

OPA 2134 (Quad - output) OPA 4134 (Dual - input) ULTRA LOW DISTORTION: 0.00008% LOW NOISE: 8nV/Hz TRUE FET-INPUT: IB = 5pA ? HIGH SPEED:
SLEW RATE: 20V/s BANDWIDTH: 8MHz COST (BLA uses these for the their upgrade) About $3.10
LT1359 (Quad - output) LT1358 (Dual - input) 25MHz Gain-Bandwidth, 125V/Β΅s Slew Rate, no data on distortion COST About $9.70 ea
LME49740 (Quad - output) LME49720 (Dual input) THD+N (0.00003%) Gain Bandwidth 55MHZ, 20V/Β΅s Slew Rate COST About $3.82 ea

AD8513 (Quad - output) AD8512 (Dual input) are only available in solder only packages. WIDE BANDWIDTH: 8MHz HIGH SLEW RATE: 20V/s LOW NOISE: 8nV/Hz (1kHz) LOW DISTORTION: 0.00008% high slew rate of Β±20V/s COST About $12.28 ea

Cost is approximate and based on purchase of 4 units. Discounts can be had when purchasing in bulk - but in bulk far higher than what a DIYer would ever need.

I think I am going to try the LME49740 as these were specifically designed for high end audio.
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