Completely Wrong Forum I Know

[csp]

I realise that it is the wrong forum, but because of the problems that I am having with a doinated d8b, I would like to install a Mackie TT24 desk, but I am having a problem in that there is no sound coming from the monitor output.

Does anyone on this forum have any knowledge of this desk and its set-up, or know of someone that might. I am sure that I have done everything correctly, but the manual is not all that great in details.

Any assistance will be greatly appreciated. I can be PMed if required.

David

[csp]

Problem solved -- took about 30 secs and about 2+ hrs to remove and replace the bottom cover -- never seen such a stupid bottom plate system/design --- nothing like the d8b but rather a full wrap around metal piece that when removed lets the chassis move so that when replacing non of the screw holes line up and there is no easy way of lining them up. I had to finally use a couple of sash clamps to squeeze everything back together and even then I had difficulty. After getting most of it back together I had to place it right way up and drag the desk so that the back of the desk was hanging over the edge of a table and then lay on my back and use a torch to see the holes (more calmping required) to get the last ten screws into place. I would love to know how they did it in the factory --- or is that the real reason that they ceased manufacturing the desk !!!

The problem was that the ribbon cable going from the Utility board (where the three non working pots are) to one of the main boards had fallen out --- almost appeared as if it had been taken out fir some reason !!!. The ribbon cable plugs are entirely differrent to those on the d8b and far superior in design.

One thing that I did discover from looking at the 40+ screws holding the base cover in place, was that someone, before I purchased the desk, has had the bottom off, because some of the screw heads (Philip Head) were badly worn.

David

[Y-my-R]

Instead of responding to the IMO unrelated "External Word Clock" thread, I'll attempt to move the discussion about this problematic TT24 unit over here, since the title of this thread is more befitting, considering that this is a specific D8B forum (but since there's no comparable TT24 forum, I do think it makes sense to have a thread about this, here... but maybe without hijacking the other thread about external word clock.

For context for anybody who's reading along, here's a (slightly cleaned up) direct message I got from David/csp about issues with his TT24 (that may be clocking related... but again, not a D8B, so this should have it's own thread, IMO... and since it already exists, here we are):

[previous paragraph redacted - this paragraph slightly modified] Last year I acquired a 2nd hand Mackie TT24, which physically looks Ok, but I think has possibly had a hard life (not by travelling, but eg a UFX2 card inserted up side down, so probably now blown up and not working and nothing on ebay).

I have only just stated to use the desk having just installed it in the Music Centre where the donated d8b was to go. Actually only turned it on for the first time two days ago.

This morning I discovered a problem that I have no idea about.

I connected the desk (via optical cables) to the HD24 recorder and powered the desk, setting the clock to Internal 48k and the H24 to Optical sync and 48k.

On raising the desk's Master fader there was low level signal showing on the Vu meters and on powering the monitors I could hear what sounded like a fast clicking white/pink noise sound. I then tried all possible combinations that the desk and HD24 would provide, but still the noise was there.

I then selected the "Word" clock option on the desk and the noise ceased, but there is no external clock connected.

I then removed every cable going to/from the desk and re-set the desk to Internal 48k but the noise was still there.

Ultimately I tried the 44.1k option and immediately the noise stopped --- I have as yet not re-conncted anything to the desk.

Can you possibly give a clue as to why there is this noise when 48k is selected but not there with 44.1k. I really would prefer to use 48k.

I have not tried the 88.2 or 96k options as they will both greatly decrease the number of recording tracks possible and I will generally require all 24 tracks on the HD24.

While typing this message, I just though, as he has the UFX2 card inserted up side down (unless someone has re-wired/turned up side down the connector), could this be causing the problem --- I have not tried removing the card and re-booting, but will do so tomorrow morning to see what happens !!!!

Any thoughts will be greatly appreciated.

If emailing, you can get me at --- [personal e-mail address removed]

I'll share my response in a separate post below, to make this easier to follow as a question/response style thread.

[Y-my-R]

Are you saying that you noticed that the UFX2 card was inserted upside down, but rather than removing it, you turned the desk on, risking to fry the desk in the process?

Before doing anything else, I'd remove that card first, and check for fried components around the slot it plugs into. Hopefully, there's no voltage passing through the card, but just going in from the desk... if so, hopefully only that UFX2 card went bad and not the desk... and if you're lucky, there was no damage at all, if no power was applied to critical components via the wrong pins on that card.

As for 44.1 working OK, but 48 NOT working... I mean, that UFX2 card, if the pins are connected all wrong, could spit all kinds of nonsense into the system, and it's unpredictable what would happen if inserted wrong. So, I'd start there.

Otherwise, I don't think there's a separate crystal for 44.1 kHz and for 48 kHz - should be the same one, but I don't really know what's going on inside those little clock ovens. Maybe something that regulates the speed at which that crystal should oscillate... like, a voltage controller in the circuit, before the clock crystal/oven...?
That's usually a small-ish silver colored component.

But again... I would first remove that UFX2 card if it's inserted wrong. That could cause all kinds of havoc or destruction.

Other than that... unless you're working for video/film, I see no reason at all to work in 48 kHz, and as stated in various posts before, the seemingly "higher" sample rate, at least in theory makes a "for CD" end-result worse, because the re-sampling and "odd math" that happens in the process (i.e. the pulse=on/pulse=off stuff I mentioned in that other post fall in-between all the time, and create an additional noise floor, that wouldn't be there, if you'd start in 44.1 kHz to begin with).

It's different if you work for film/video because the typical frame rates used for that, align better with the 48 kHz sample rate. So, it really depends what the end result of such a recording project should be.

I don't think that anybody would be able to tell in a blind test, if something was recorded at 48 kHz and then re-sampled to 44.1 kHz (unless it's classical music with very quiet passages or other material where every half-dB or so of noise-floor matters).
But if you have the choice to start out with a better suited sample rate, I'd go with 44.1 kHz for audio CDs or music in general (although it doesn't really matter if producing for "online-only" releases).

Everything I do is in 44.1 kHz, because I don't usually do music for film/video, btw. Anybody who tells me that they go with 48 kHz because of the improved quality because of the higher sample rate, immediately gets a "doesn't know what he's talking about" stamp from me, hahaha.

...and sorry... I don't want to move this to a direct e-mail conversation because of my tech support past. I actually quite enjoy, that I'm not directly reachable for tech support questions with an expectation for a timely response.
If I choose to help with technical problems, I want to do so on my own time. And usually more for the purpose of helping anybody who reads along in the forums... and not start a new "direct tech support" hobby. I've been doing that for waaaaaaaay too long as a job, and am SO glad that I escaped that. So, I'm not gonna volunteer to do 1-on-1 tech support again in my free time, sorry.

With all that said, I'm happy to help here, whenever I get to check my forum mail or via responses to forum posts... but don't want to open a direct communication channel for support questions, sorry.

I hope the desk will spring back to 100% working after you pull that wrong card out. Best of luck with that!

(...and I thought you posted something about that TT24 a few weeks ago, already and said you turned it on, then. Kind a confused about that and at least for tech support purposes, there's nothing worse than only being told part of the story and withholding potentially other important details, such as what has happened previously... e.g. with the ribbon cable you said that came loose. Anyway... I've never seen a TT24 in person, so I wouldn't be much help with that one, anyway).

[Y-my-R]

In this context, David's response to the "External Word Clock" thread should now make more sense:

Y-MY-R,

Even with the few mistakes (???) It was still the best/easiest description of clocking that I have read.

Re the TT24 the person that I purchased it from (it was basically wrapped up whern collected) had apparently been using it and unfortunately I did not inspect the UFX2 card before powering the desk when I got home from collecting it, only saw the situation a couple of days ago, when I happened to look at the back of the desk and saw that the name and model of the card was written upside down and that there was a small gap at the top of the area where the card was inserted.

I prefer not to have to remove the base cover as there are more screws than about 10 d8b desks (!!!) and as it is a wrap-around cover, once removed it is almost impossible to re-align the screws when replacing the cover, as the desk's frame is not rigid. Also everything is working in the desk (apart from the clock situation),

It would just mean that if using Light pipe from thr HD24, that Bank will have no effects as the Digital Bank (as the desk was designed) had no DSP on that Bank --- hence the need for the UFX2 card. I have not as yet tried to see if there is actually any DSP/Effects on that bank, if there is then it means that the card has been inserted correctly, but something inside the desk has been reveresd or that the UFX card's PC board has been removed from its face plate and screwed back on reversed (if that makes any sense in the way I have put it).

Might definitely have to dig out the donated d8b again and try a few new suggestions and possibly buy the spare cards that were offered to me before Christmas --- just more expence and possibly more wasted money !!!!!

Any way thanks for the clock info and 44.1k is Ok by me.

David

I'll response in yet another post below (i.e. question/response style)

[Y-my-R]

As mentioned above, I haven't even seen a TT24 in person, but when looking at pictures of the back panel, it appears that the two expansion card slots are accessible from the rear panel. Is this where the UFX2 card is installed?
(I'd have to read the manual to figure that out, and don't really have much of an intention to learn about the TT24... not planning to get one).

If so, still, the first step I'd suggest, is to remove that card and check if the desk can operate at 48 kHz after that (...and as you tried before, having all external cables disconnected for the first test, is a good idea since you won't have any potential clock-mismatch coming into the desk, that could cause an issue like that).

And sorry to say... even if the UFX2 card is installed inside the desk in a way where it would be necessary to take the bottom panel off, that's STILL the first thing I'd try.

I mean, what you're essentially saying is "I have a problem with the desk, and noticed something that is most likely wrong, that could mean that pins that shouldn't make contact inside the desk, potentially DO make contact. I don't want to deal with this, though. Can you fix this in another way, where I don't have to do the unpleasant work?"

...the short answer to this would be "No." I've never used this kind of desk, you identified a potential serious problem with how the desk was assembled... so, that IS the place to start troubleshooting.

If someone else knows more about the TT24 and what could cause that specific problem, please chime in. But with the information given - I don't know what else to say, than to first try if the problem is still there, when removing the thing that is a likely cause of problems.

And just to make sure this is 100% clear: I'm NOT suggesting to flipt the UFX2 card upside down (or right side up) and then power on the desk. I'm suggesting to (for the first test) REMOVE the UFX2 card altogether, and then try with 48 kHz and check if you still get the same problem.

I mean, I get that you want to use the FX DSPs on that card... but we're not putting the desk to use, yet. We're troubleshooting and trying to isolate where the described problem is coming from... and a card that appears to be installed wrong, is a very, VERY good pointer for a potential cause.

[csp]

Y-my-R,

Thank you for doing all of that.

The card is inserted into the top slot of the two card slots on the rear of the desk.

If you consider the card slots on the d8b, when all cards are inserted (correctly) there is no space between the individual cards or the two ends of the section. Unlike the d8b the card slot section runs horizontally rather than vertically as in the d8b, so that when (as in the case with this desk) a card is inserted (say) in the top slot and the blank plate is left inserted where the bottom card would go, like the d8b there are no gaps.

With this desk if you look from the rear of the console, the UFX card (which is in the top slot) running along the top edge of the card frame is a gap of about 1/8th inch and the botton plate rather than sitting snug within the frame is hanging over the bottom edge of the frame by about the same 1/8th inch, much the same effect as if you placed (say) the Apogee card back the front into a d8b then put blank plates oover all of the other slots you would see a gap somewhere.

I will be at the Centre later today and will pull out the card and try the desk to see what happens, but prior to doing this I will do a quick test to see if something (say one of the HD24 optical cables) plugged into the Digital bank has any DSP, Effects, EQ, etc. If it does then it suggests that the UFX card is actually working correctly and that for some reason the socket has been reversed somehow or rewired for some reason !!!!!!!

Do I really want to have to remove the base plate again --- a very definite NO !!!!!

Again, thanks for your assistance.

David

[Y-my-R]

Here's a picture of two extension cards (the bottom one a UFX II) installed in the rear panel of a TT24:

TT24_rearPanel_RemovableCards_s.jpg (Array KiB) Viewed 303 times

Looks like the writing on the cards is the right-way up... would be weird if someone rewired something internally, or flipped the face plate of that card around... like, why?

I still don't get why you have to take the bottom off of the TT24 to take that card out...? Looks like you can just pull it out from the back - just like on a D8B...?

Anyway... personally, I'd first try WITHOUT the expansion card in there... not that the TT24 only starts activating the DSP card and applying voltage to the wrong pins, once you add an effect in software. It's unlikely, and power is probably applied as soon as you turn the TT24 on, but it's possible that it only gets activated when used.
...but if so, you might just fry something the moment you try to activate the effect. (Again, very unlikely, but not totally impossible).

Curious to hear how that test went! Best of luck!

[csp]

Y-my-R,

The photo is exactly the way it should be, but in this console the space above the U100 card in ther photo is much wider and the bottom of the UFX card is possibly level with (or lower) than the bottom of the two small screws. When I go to the Centre later today I will take a photo and post it.

The card can definitely be removed without removing the base, but I will need to remove the blank face plate because the UFX card only has one of the holding screw devices the other side is a Phillips head screw --- what has happened to the other mounting screw I have no idea !!!!!

The reason for removing the base plate was to get inside the desk to see if the UFX card socket had been tampered with, BUT I will wait untill I do the tests later today before even considering that job.

David

[csp]

Y-my-R,

Somehow I think that I am jinxed with 2nd hand Mackie desks !!!!

Went to the Centre mid afternoon and booted the desk to see what the UFX2 card was doing (ie was there any DSP, effects, etc) and found that the card was not recognised as being inserted. At that stage the clock noise was present. I then discovered that if I removed the Optical cards one at a time the level decreases until all cables have been removed at which time there is no noise

Then turned off the desk and removed the card --- I was wrong about one thing, it did actually have the two standard Mackie securing screws. I took a photo of the card before removing it. Once removed I inspected the slot and the card was definitely inserted correctly --- components facing down --- components facing up the card would not fit. I have removed the face plate and installed it correctly after I took the photos and apologies for the quality of the photo but my cell (mobile) phone is not great with close up photos !!!!!

Rear Mackie TT24 Desk.jpg (Array KiB) Viewed 251 times

For some resaon completely unknown to me, someone has appeared to have actually removed the face plate from the UFX PC board and then screwed it back on but upside down --- makes no sense to me why someone would do this --- unless the mistake took part on the Mackie assembly line !!!!!

Then I did a bit of clock setting changes and ultimately got to a point where I had no noise (desk --- Internal, 48k, SMPTE and the HD24 --- Optical, 48k). The 48k on the HD24 was blinking indicating that it had not locked to the desk, but it worked perfectly --- I have not experienced this situation with my d8b desk and my HD24's. Any other combination of the desk and HD24, there was the clock noise and generally no sound or Vu reading.

After getting the desk to put out sound, I decided to undertake a VERY detailed test of everything, but an introduction to the desk first.

Under the LED display screen there are a number of knobs and switches that allow the operation of the various features of the DSP and EQ section for each channel.

1. The Digital Bank was as though the clock card was not inserted as every option was blank and this was on both the desk's LED screen and the external monitor --- via PC (Mackie's TT Control program) being fed from the desk via USB.

2. The Analogue Bank, displayed most of its features for each of the 24 channels, but altering settings, although visable did not appear to alter anything audibly --- no EQ, effects, dynamics, etc.

3. The Returns Bank that takes as the first 8 faders all of the external analogue inputs was as for the Analogue Bank. I did not try the other features/inputs of this bank.

The motorised faders on all three main banks are working correctly and the desk is passing audio as expected, BUT why the other sections/features of the desk appear not to be working I do not understand.

I am seriously starting to think that I was sold a very sick and possibly very much fiddled with desk, so I think that it is going to have to be removed and back to square 1 with the donated d8b desk, or right back to the originally donated Behringer analogue desk.

It is times like this when I really wish that there was someone in this country who was an expert on the desks that I could call on to sit beside me and work out if it is me or the desks that are faulty --- my wife woud say it is definitely me !!!!!!!

WHY DID I EVER ENTER THE AUDIO/ELECTRONICS FIELD AS A VOCATION WHEN I HAD PLANNED RIGHT THROUGH SCHOOL TO BE A PHARMACIST !!!!!!!!!!!

David