Akai DPS24 ADAT expansion card woes: no audio

[Kwackman]

Red Herring time....
ADAT can be 8 channels of audio, or a single stereo feed.
From memory RME can switch between these modes in software.

Probably not relevant, but, just in case!

[Drew Stephenson]

Red Herring time....
ADAT can be 8 channels of audio, or a single stereo feed.
From memory RME can switch between these modes in software.

Probably not relevant, but, just in case!

Just to be picky...
The toslink optical connection can carry ADAT or SPDIF. ADAT can be up to 8 channels depending on sample rate. SPDIF is always stereo.
The socket is the same but the configuration isn't and needs to be set accordingly.
[/pedantry]

[Kwackman]

Just to be picky...
The toslink optical connection can carry ADAT or SPDIF. ADAT can be up to 8 channels depending on sample rate. SPDIF is always stereo.
The socket is the same but the configuration isn't and needs to be set accordingly.
[/pedantry]

Drew, have you not got anything better to do, like spotting frequencies in choirs no other humans can hear?

PS. You are correct of course, that was very sloppy terminology on my part.
I'll be in the corner huffing for the rest of the afternoon......

[Drew Stephenson]

I'm sorry about the choir thing too.
But it's definitely there.

[forumuser840717]

Yep, and all the RME's optical ports can function as either ADAT Lightpipe or SPDIF ports, as can the TOSLINK connection on the DPS24 itself. Hence asking whether there was a known working link passing clock and ADAT audio to use as a test source. I wondered whether the RME or DPS24 might be set to SPDIF on all or some of the ports.

If everything were set to SPDIF then obviously they'd sync up but wouldn't pass 8 channels of audio (and they'd show up in the DPS24 patch pages as a two channel link rather than 8 channel). Also, if the RME were set entirely to SPDIF, it wouldn't sync into the ADAT ports on the expansion board (as they don't do SPDIF) but could sync and send two channels into the DPS24's optical port if that were set to SPDIF. Gotta love digital formats!

The lack of output LEDs on the DPS24 expansion board isn't a good sign though.

[Anthony gilbert]

I wondered whether the RME or DPS24 might be set to SPDIF on all or some of the ports.

Thanks again for the suggestions. It's set to ADAT. One of the nice things about the RME software is it displays the source type and sample-rate of the incoming signal it syncs to. I've had previous RME Digiface products and they remain pretty good.

The lack of output LEDs on the DPS24 expansion board isn't a good sign though.

Agreed. I've had the DPS24 open over my lunch break. I've checked the pins of the DPS24 option interface PCB. I've also checked the micro-ribbon cables to the interface PCB. The other end of these go underneath the main PCB and aren't visible. A strip-down looks to be a "fair job", and one which may break more items than it may fix.

Next step is to try another IB-24ADT expansion card, or find someone to test mine. I've made an enquiry with VST Services.

[forumuser840717]

Thanks again for the suggestions. It's set to ADAT. One of the nice things about the RME software is it displays the source type and sample-rate of the incoming signal it syncs to. I've had previous RME Digiface products and they remain pretty good.

I'm a big RME fan. Since getting my first RME card - a Digi96/8 PST in about 2002 (still got it and it's still working fine in an old WinXP machine), I went on to get another one the same (sold a few years ago), then in 2005, an HDSP-MADI and, later, HDSPe-MADI and HDSPe-MADI-FX Triple MADI cards (all now gone in favour of external interfaces to make it easier to move them between computers). I currently have 19 assorted RME boxes - mostly MADI related - and couldn't be happier with them. If only all manufacturers were as reliable and straightforward.

A strip-down looks to be a "fair job", and one which may break more items than it may fix.

Definitely try another expansion board if you can get one, before taking everything apart. It's not terribly difficult to strip it down but it is generally fiddly, involving more screws than a screwy thing and, as the DPS is getting on in age now, there's lots of potential to accidentally make things worse so it's best avoided until you eliminate other possibilities.

If you don't get any joy with VST Services, it might be worth trying a post in the SOS Reader Ads Wanted section.

Failing that, I don't know whether you've tried it but there used to be a really good user board for the DPS products. I don't know how functional it still is but there's what looks like an archive of it here. If it's still running, there might be some sources of parts there or current users who might be able to help.

Please do let us know how this develops and any outcome as it'd be good to know what's wrong for future reference. All this chat about the DPS24 has reminded me what a great bit of kit it is and how much I miss mine. It took me ages to sell them as, even when I'd stopped using them, every time I started the sale process I was reminded how much I liked them and kept changing my mind

One other thing - do you have the ak.Sys TrackView DPS24 PC software for the DPS24? It probably needs a fairly ancient PC to run it - mine was on WinXP - but it does have some useful facilites that make things like metering and editing clearer. There might be a version floating around online but if not and you think it'd be useful I probably still have it lurking on an old hard drive somewhere.

[Anthony gilbert]

Please do let us know how this develops and any outcome as it'd be good to know what's wrong for future reference.

I certainly will do.
I thought I was an RME fan! It's not cheap but a classic case of getting what you pay for - especially the longevity of driver support. That's a rare thing these days.

This was my first post on the SOS forum and the response, knowledge and helpfulness has been quite overwhelming.

I've been an SOS reader since the days of Electronics & Music Maker. Never thought to ask the forum before today, and I'm now wondering why.

The DPS24 continues to impress (other than the obvious exception). I get 20 live mixer channels currently (12 analogue and 8 ADAT), using the old trick of armed track channels. I can output to the RME using an 8-buss output, or multi-passes of track-per-channel. Above all, I find it still delivers musical results whilst being intuitive and tactile.

I'll certainly keep on hunting for a solution to keep the old thing alive.

Thanks again everyone for your time and assistance.

[Anthony gilbert]

Quick update and a question...

I've been scouring all the usual places for a replacement ADAT expansion card to try. No luck to date.

This creates the question: what if it's not my existing expansion card? I've done continuity and power checks on the expansion card and it's all good. It is also detected by the DPS24.

Is anyone willing to test my existing ADAT expansion on their DPS24? I will gladly post it for "field trials", and supply it with some beer/wine funds...

[OneWorld]

Do you have another audio interface you can try. I too use RME and I too get a no audio issue using one of the ADAT ports. I have some external effects which I want to use as insert effects, which use ADAT (in SPDIF - stereo) mode, I have set up the RME for ADAT to work as stereo, I had the red lights showing on the ADAT output, etc but try as I may I simply cannot get get the audio into the RME, in this insert effects scenario, but the ADAT works in other setups. It has to do with the patching or clocking I am sure.

I have given up and used the analogue i/o instead.

OK I guess this is a 'longshot' and quite often these 'have you tried' suggestions often lead you down a garden path and you end up given a dis-proportionate amount of time to something that will come to nothing but I suppose in the absence of anything else then owts better than nowt and it might be worth a try.

Best of luck. The DPS24 is a lovely machine and I suppose came along at the wrong time, when HDD recorders finally gave way to DAWs

[James Perrett]

I have some external effects which I want to use as insert effects, which use ADAT (in SPDIF - stereo) mode, I have set up the RME for ADAT to work as stereo, I had the red lights showing on the ADAT output, etc but try as I may I simply cannot get get the audio into the RME, in this insert effects scenario, but the ADAT works in other setups. It has to do with the patching or clocking I am sure.

It may just be sloppy terminology but I just wanted to check... You can only run ADAT format signals in stereo if you are using a 192kHz sample rate. So do you have all the RME inputs and outputs set to SPDIF or ADAT? It should be SPDIF. Are you using the RME as the audio clock master and is everything else set to external audio clock?

[Hugh Robjohns]

There is a lot of confusion over the optical interface, and routine misnaming is a common cause.

The socket is identified in technical circles variously as the EIAJ RC-5720, the CP-1201, or the JIS C5974 F05 -- but probably the most common shorthand is the JIS F-05.

In consumer hi-fi circles it is more usually known as the TOS-Link socket, after the 'Toshiba Link'.

But just like the humble XLR-3, the socket itself doesn't define its function. The JIS F-05 is regularly used as the interface connection for either S/PDIF two-channel digital data or ADAT multi-channel data -- and many platforms allow the electronics to be configured manually to support either format.

In both cases, the S/PDIF or ADAT data carries embedded clocking data, so can be used as the clock source for the receiving device if suitably selected for that function.

Common reasons for non-working optical ports are:

* Wrong data mode selected.
* Wrong clocking source selected
* Multiple unsynchronised sources feeding the device simultaneously
* Excessively long or poor quality optical fibre
* Kinked or damaged fibre
* Dust or dirt in optical sockets
* Optical fibres connected to the wrong sockets (in/out reversed)

[Anthony gilbert]

Thanks for all the response on ADAT and optical.

For my DPS24 ADAT expansion card, the problem is quite fundamental as described earlier in the thread. To recap, the ADAT expansion optical-out ports x2 LEDs flash on boot, but then go out. The in-built ADAT optical-out port LED x1 happily glows red - and does so irrespective of clocks, config etc.

The control of the optical LED may well be done by the DS24, but perhaps acting on a control signal/state of the ADAT expansion. This is why I'm wondering is it the DPS24 or the expansion card?

[Hugh Robjohns]

To recap, the ADAT expansion optical-out ports x2 LEDs flash on boot, but then go out. The in-built ADAT optical-out port LED x1 happily glows red - and does so irrespective of clocks, config etc.

I wouldn't assume that to be a fault. I have several bits of kit that turn off the optical outputs when not assigned (so the red light goes out). The Akai may be the same.

The control of the optical LED may well be done by the DS24, but perhaps acting on a control signal/state of the ADAT expansion. This is why I'm wondering is it the DPS24 or the expansion card?

As you mentioned earlier, you really need a current DS24 user to compare and confirm... Sorry I can't help, but I hope you get to the bottom of it.

[Anthony gilbert]

To recap, the ADAT expansion optical-out ports x2 LEDs flash on boot, but then go out. The in-built ADAT optical-out port LED x1 happily glows red - and does so irrespective of clocks, config etc.

I wouldn't assume that to be a fault. I have several bits of kit that turn off the optical outputs when not assigned (so the red light goes out). The Akai may be the same.

Hugh, that's worth knowing and very helpful. Thanks.

[OneWorld]

I have some external effects which I want to use as insert effects, which use ADAT (in SPDIF - stereo) mode, I have set up the RME for ADAT to work as stereo, I had the red lights showing on the ADAT output, etc but try as I may I simply cannot get get the audio into the RME, in this insert effects scenario, but the ADAT works in other setups. It has to do with the patching or clocking I am sure.

It may just be sloppy terminology but I just wanted to check... You can only run ADAT format signals in stereo if you are using a 192kHz sample rate. So do you have all the RME inputs and outputs set to SPDIF or ADAT? It should be SPDIF. Are you using the RME as the audio clock master and is everything else set to external audio clock?

That might be the issue then, as the external equipment does not have the 192kHz sample rate. It is not such a big issue as I am using the analogue instead

[Coz14]

Hi Anthony - I think I might be able to help you out with your ADAT expansion card. I am in a similar situation as you which is how I found this post. I have a DSP24 which I bought in 2004 and still own. I have just upgraded my PC based DAW (Reaper) and wanted to use the DPS24 as a front end (Pre-amp and ADC) to send up to 16 tracks of ADAT to my RME HDSP 9652 soundcard.

Currently I am able to send 8 tracks via the DPS24's internal ADAT port.
Back in ~2012 I found/bought the ADAT extension board. The board worked for a little while but it was a bit flakey. Whenever I sent audio out on ADAT 9/10 the gain would increases in steps until the audio was distorting. Eventually out of frustration I hot swapped the board (removing and reinserting it while the DPS was still powered on), it stopped passing audio from that point. I fear/suspect that I may have damaged the Xilinx Spartan FPGA at the heart the board.

Recently, I have had renewed interest in seeing if I can get this card working again (or at least understanding/verifying what is wrong with it). This is what led me here. I saw your request for help, and I am willing to test your expansion card. If your are still interested in help, please reach out.

Steve

[Anthony gilbert]

Hi Steve,

Thanks for sharing your experiences. Very interesting read. Funny you mentioned the Xilinx Spartan IC, which I replaced. Of course it needs programming, so no board detection at all when I did this.

I'm not able to send the expansion card over until the new year, but I would love to see if you have any luck on your DPS24.

Send me a PM if you can for details.

Cheers,

Anthony

[Coz14]

Hi Anthony - I am unable to send you a PM. I have not been given PM privileges yet, due to my lack of posts on this forum.

I just went back and re-read this thread and I have some questions. 1) Did your expansion card ever work properly? 2) When did you replace the FPGA, was this before or after you noticed the LEDs in the ADAT TX ports flashing/extinguishing? 3) Do you still have the original FPGA? As you have stated these IC's need to be programmed with the appropriate firmware. At this stage further troubleshooting is pointless without the original FPGA on the board.

Steve

[Sam Spoons]

Hi Anthony - I am unable to send you a PM. I have not been given PM privileges yet, due to my lack of posts on this forum.

Steve

One more approved post and your future posts will be auto-approved along with your PM privileges being activated.