Turtlerock Forum

I have seen on the USA internet a chap that modifies these units replacing with Burr Brown 2134 op amps to increase gain and lower noise on these units.
Has anyone else tried this and would it be economical to do as I am looking for a cheaper 8 channel digital inputs into my Digi 002R unit and thought this could be an alternative.
How easy would this be to do and where would I get the parts from as this would be my first attempt at something like this?
Would there be a better chip like the Burr Brown 227 instead that I should try?
I would be running a JLM TMP8 channel preamp into the ADA8000 into the digital in of the DIgi 002R most likely for drums so I am not sure how much the Slew rate on these chips is important.
Cheers
Dale

HA_DA_JA wrote:I have seen on the USA internet a chap that modifies these units replacing with Burr Brown 2134 op amps to increase gain and lower noise on these units.
Has anyone else tried this and would it be economical to do as I am looking for a cheaper 8 channel digital inputs into my Digi 002R unit and thought this could be an alternative.
How easy would this be to do and where would I get the parts from as this would be my first attempt at something like this?
Would there be a better chip like the Burr Brown 227 instead that I should try?
I would be running a JLM TMP8 channel preamp into the ADA8000 into the digital in of the DIgi 002R most likely for drums so I am not sure how much the Slew rate on these chips is important.
Cheers
Dale

Sounds interesting Dale - I've looked at te ADA8000 for extra inputs for my 003 as well in the past..
I'll be watching this thread for sure..
Tim..

As far as I know the ADA8000 had issues with an under-rated power supply. Mine started popping a while back so I just pulled it out of the rack altogether. If you are going to get one, make sure that someone checks out the PSU, particularly if you are changing op-amps. It should be a good machine, but I doubt it will be a reliable one.

I heard that it was only the European models that had power supply problems and that was earlier units, but I guess you can never be too certain with mass produced gear as I had bought a new Apple laptop that was DOA a few years back.
Cheers
Dale

I had one, it was ok, pre's nothing special at all. I'd give it a miss and look for a second hand presonus digimax LT, a friend just bought one for bout $450-500 i think. As opposed to putting things through the ADA8000 because that was all that was left he can now use the Digimax LT as a choice as they are more than respectable.

I've heard the Presonus mic pres are pretty transparent..

There was a huge thread on this on one of the audionerd forums ages ago (sorry can't remember which one)

After a lot of pretty thorough investigating and testing I think the consensus was that they are a decent machine as is and upgrading opamps wasn't worth the effort. However they did come up with a mod to bypass the pre's so they had a true line in. From memory the power supply issues were with the 110V units (don't quote me)

I have used one several times with either the MOTU 896 or an Ensemble as the master, and using desk or outboard preamps and have had no issues. Always worked and sounds ok. In a pinch the preamps are useable too.

I had one when I downgraded the studio before closing it :)
I thought the convertors were better then the 002 although they are all out a bit from each other .5db here almost 1db there. The pres not that good although I have been spoiled for years even with downgrade I still had Neotek, API, Calrec, Buzz, Trident desk all into the 002/be!@#$%^& combo..
I tested the DA against the Mytek I used and it was better then the 002 although not near the Mytek of course.

Is there much benefit to running a horribly expensive preamp only to have it attenuated and given the be!@#$%^& pre treatment? The line in is simply attenuated and them run through the preamp so you still have gain control. Seems a bit like paying a premium for expensive beer in a plastic cup!

Kurt wrote:Is there much benefit to running a horribly expensive preamp only to have it attenuated and given the be!@#$%^& pre treatment? The line in is simply attenuated and them run through the preamp so you still have gain control. Seems a bit like paying a premium for expensive beer in a plastic cup!

Yes I know.. Although as said I was in the downgrading phase before I just shutdown the studio. Just could not let go of my old preamps at once until I closed the door.
Although I think the be!@#$%^& sounded better then my old 16 bit digi mix convertors which I was happy to run good pres in years ago, also thought nicer then the 002 which again you run through the preamps on 4 channels..
The thing is as a engineer I was always striving for the best sound and chain I could setup. Although a lot of bands are striving for the cheapest recording they can do. The two do not mix :)
The extra money from selling my HD system with 3 interfaces and a lot of other real nice outboard went into buying a house.
Back on subject honestly this is one of the better be!@#$%^& products they have. Although you know there has been 3-4 revisions on getting cheaper parts inside and like everything be!@#$%^& some are good a lot have no QA.

as Kurt said, the line in is simply run through a pad, then into the whole mic-pre stage. The only mod that ever made sense to me, was to dump this whole front chain and provide a simple balanced line input running at unity gain. Rather than throwing away some 40db of signal then dialling back up 40db of gain.

i'm sure it's possible and installing higher performance opamps is possible....but is it worth it? Probably cost more to do all this than the unit retails for. ( or do they give them away now??? ) Never the less the actual converters are pretty good.

Rob

one word. JLM, people.

http://www.jlmaudio.com/user/viewtopic.php?t=22

"8 channel transformer to ADAT interface. The 8 audio transformers step down the +18dBM full scale inputs to match and feed the A/D chips directly so power needed is only one 5v rail. 24bit 44.1k and 48k with word clock in and out. "

oh Joe, you've done it again.

"yeah, but tell 'em the price dad!"

I run three of the ada8000's for work, mainly for the outputs so I can't comment much about the sound of the pres.

I can however say that 1 of the 3, the newest one, has started clicking and generally being a pain when driving all 8 out puts. It only happens when I push it hard for a while, it also gets quite hot compaired to the other two.

there are a veritable mountain of threads on Prodigy/the Lab re: the ADA8000

Most of them are devoted to bypassing the mic pres, to make it solely a line input device. I think Gyraf even has on his site a schemo with his suggested changes. I've contemplated exploring it down the track when I run out of nis and outs on my Multiface.

Hmm, nis. Queue Chrisp and another Holy Grail quote :)

Tony wrote:I run three of the ada8000's for work, mainly for the outputs so I can't comment much about the sound of the pres.

I can however say that 1 of the 3, the newest one, has started clicking and generally being a pain when driving all 8 out puts. It only happens when I push it hard for a while, it also gets quite hot compaired to the other two.

That's what mine did, little clicks when lots of channels running. A real PITA. I binned it and replaced it with a Yamaha 02R that has been sitting around, a far more versatile box... ;-)