Behringer ADA8000 modifications..

[gyraf]

Hi Group,

I'm looking for a schematic of the Behringer ADA8000 Ultragain Pro-8 A/D D/A converter.

The thing is that this box is extremely inexpensive, and has ADAT lightpipe ins and outs. Supposedly based on the not-too-bad Alesis chipsets.

So it's an obvious target for a DIY modification project.

Mods could possibly include analouge path, direct monitoring, metering.

Behringer themselves are less than helpfull when it comes to their digital stuff - and we're not going to buy this box and start modifying without a proper schematic..

Anyone?

Jakob E.

 

[Gulistan]

The thing is that this box is extremely inexpensive, and has ADAT lightpipe ins and outs. Supposedly based on the not-too-bad Alesis chipsets.

Yes, ADA8000 is based on Alesis (now WaveFront Semiconductors) A/D (AL1101), D/A (AL1201), an ADAT encoder (OptoGen AL1401) and an ADAT receiver (OptoRec AL1402).
Take a look at application notes and datasheets.
The ADA8000 is a copy of the RME AEB8-I (I had schem for it if you want), and the schem is simply an expansion to 8 channels (instead of 2)of the appnote given by Alesis for OptoGen and OptoRec.

 

[gyraf]

If it's a true copy of the RME AEB8-I, I would very much like to see the schematic for that one..!

But still, a "real" schematic would be preferable before we buy a unit to experiment on.

Gulistan,

If you have the RME AEB8-I schematic in electronic form, I would very much appreciate a copy. My large-email receiving adress is jakoberland (at) feedback (dot) dk

Jakob E.

 

[bradzatitagain]

Jakob, I've tried to get Behringer scats in the past, you won't get anything from them for ANY unit they build. Your best bet is to find a rogue B. approved repair shop, but those guys are bound by a signed agreement they make that they will not provide scats to anyone, ever. You could become an authorized Behr repair guy and get it all, however. My terse opinion is B rips off so many others' designs they don't want anybodys' lawyers to be able to succinctly prove it in court. I'd bet if you got the scat from the Alesis specs and started to do just a small amount of reverse engin. you'd find a dot to dot copy of the gear Gulistan called out.

It's so easy to hate Behringer.

 

[synthi]

Hi friends,

I have 2x ADA8000 here, they sound very good, better than some expensive top converters. the ada8000 may be one of the best B*hr*ng*r products, they even have a toroidal psu inside

I saw the post in the forum about changing the buffers in other AD/DA converter and I think the ADA8k would be a good candidate for mod.
Gyraf, I`m sorry I can`t help you with schematics, but I could provide photos for the inside of the unit if you are interested.
I`d like to "bridge" the gain pot, I don`t need the mic preamps,I only use the line inputs but I think that having a gain for the line in is because the signal passes thru some kind of (crappy?) amp..
Any clues?

Thanks!

Synthi.

 

[Steve Jones]

As much as I can't stand Deadringer, I am going to buy one as well, because with decent amps on board it would be a really useful box, and boy is it inexpensive. A DIY mod to the analog circuits would be a killer!

 

[Michael Krusch]

Yeah, photos from the inside would be nice.

 

[Steve Jones]

PLEEESE someone get a diagram quick! :grin: I am busting to see what can be done with one of these units once Jakob is unleashed upon it.

 

[rafafredd]

I´m also going to get one!

 

[synthi]

I was pretty sure I saw photos from the inside in our group...
I search a bit and they are here:

http://www.groupdiy.com/index.php?topic=2121&postdays=0&postorder=asc&highlight=alesis+ad&start=30

Let me know if you need other photos!
I can`t wait to modify mine..., I`m sure we will end with a hi-end converter at outlet price

Thanks.

Synthi

 

[rafafredd]

Well, it shouldn´t be that difficult to get rid of the line/mic input stage...

Just try cutting some pads and feeding the signal directly into the converter. Don´t forget to use a cap and an attenuator before the converte. Check the converter mzx input level!!!

 

[pilo]

Hi

I has I've already said it before, I'm working on an ADAT convertor, using al140* and al1101 from alesis, and a pcm1798 from ti (I wanted to try a better dacs than alesis one, maybe it's a bad idea, see below).

The adc side works great, I use TI pll1700 for clock generating and a simple input buffer.

Now the DAC side... it's becoming a nightmare! I can only hear a verryy noisy sound, when I get sound... But when I switch off the converter, while sending sound to it, I can here for about 0.5s a very good and clear sound (and I can see it on the scope). So that's my problem by now, and I don't know what is the problem...

schematic and some pcb layout here :
http://membres.lycos.fr/blendinpulse/adat/

Making a diy adat converter using Alesis chip is not very hard I think, and maybe a cheaper and better solution than modding an ADA8000.

 

[synthi]

Hi Pilo,

I dunno you can get cheaper than modifying an ADA8k, just the case, PSU and XLR/jacks/power switch/hardware worth the price of a new B*r*ng*r.

Also I want to ask you did you choose the TI for the DA part? I`m using my ada8k for DA and sounds near as good as the Swissonic DA24...

rafa: the question is what pads to cut? what cap and attenuator values? and where to feed the signal?. I`m sorry but I need some guides, my electronic knowledge are basic...

Synthi.

 

[pilo]

just the case, PSU and XLR/jacks/power switch/hardware worth the price of a new B*r*ng*r

mmm I didn't though about that, and you're right...!

did you choose the TI for the DA part?

mmm I don't understand the question, but, I think the al1201 DAC from alesis is a very good one... I choose TI because... I wanted to, but I start thinking about buying one al1201...

 

[synthi]

the question is : why did you choose the TI for the DA part?

I`m hungry and eat the first word

Josue.

 

[pilo]

why did you choose the TI for the DA part?

because I can get sample of ti's dac... (maybe a bad reason...)

I`m hungry and eat the first word

 

[saxtim]

Don't forget this thread for those interested in adding a cheap 8 channel Adc to mic preamps and such:

http://www.groupdiy.com/forum/viewtopic.php?
t=2121&highlight=adat+lightpipe

Towards the end of the thread someone pointed http://www.zzounds.com/item--STOADAT

8 channels of ADC for $100. I'm not sure if anyone has used this before, but I guess if you're going to bypass the mic/line amp seciton of the Beh. and run straight into the ADC then this card might be a cheaper option, especially if you were to install it into a DIY mic pre rather than a separate box (save on jacks etc). Think it ran of a +/-5V supply from memory

tim

 

[bradzatitagain]

[quote author="saxtim"]Don't forget this thread for those interested in adding a cheap 8 channel Adc to mic preamps and such:

http://www.groupdiy.com/forum/viewtopic.php?
t=2121&highlight=adat+lightpipe

Towards the end of the thread someone pointed http://www.zzounds.com/item--STOADAT

8 channels of ADC for $100. I'm not sure if anyone has used this before, but I guess if you're going to bypass the mic/line amp seciton of the Beh. and run straight into the ADC then this card might be a cheaper option, especially if you were to install it into a DIY mic pre rather than a separate box (save on jacks etc). Think it ran of a +/-5V supply from memory

tim[/quote]

Does the STOADAT get you both in and out, AD/DA, or just AD?

 

[SonsOfThunder]

It was me that had pointed to that card in the thread.

I believe its just AD.

HTH!

 

[bradzatitagain]

[quote author="SonsOfThunder"]It was me that had pointed to that card in the thread.

I believe its just AD.

HTH![/quote]

10-4 that, read the pdf specs AFTER I posted, duh. It can't be that hard to jump past the pre's in the B-word ADA8000, it's just a matter of whether or not it's worth it. If there's no sonic difference between it and the convertors in the Digi001, at least in my case, there's not a lot to merit the effort. BUT since it is the case that you can connect the ADAT in to the ADAT out on the B-word box with one cable and have 8 analogue to analogue mic pre's in a row, the topology is at least worth considering the effort, especially if the convertors are easily upgraded (not, I'm sure.) I'd toss 8 Ampex MX35 EF86/PF86 cathode follower pre's in there and have a dynamite box.

Does anybody know what the spec'd convertors are in the ADA8000?

Ah, semi-poverty....