ADAT SVHS recording - anyone have any knowledge

[HSLand]

Thanks for the welcome.

The problem with sending them off for repair is that it's probably cheaper to just buy another one. I guess I just refuse to let them defeat me

[km6xz]

If there is a constant Err 7, and the tape path is clean, don't adjust anything hoping to get the deck to work unless you have a scope and calibration tape. The most common cause on a low hour machine that is clean and properly adjusted is 1/2 of the modulated waveform from the Helical head is missing. There are two heads and a full rotation scans the tape with the heads mounted on opposite sides of the rotary drum scans with one head for 180 degrees and the opposite head scans for the second 180 degrees. A switching circuit connects one head then the second and the PG signal does the switching between the heads. I would wager the balance video amplifier chip inside the head is bad. Usually that requires head assembly replacement(expensive if it is even available) but with careful work the chip can be replaced. The mechanical alignment of the motor and magnetic drum that generates the PG on the bottom of the motor need to be aligner precisely after reassembling the head. You can verify the chip problem by using a scope to see if only a RF envelope is seen for 180 degrees of the heard rotation. If anyone still has that Alesis custom video amp chip it would be Ruth at advancedmusical@ca.rr.com in Culver City CA She has the last remaining stock of Alesis parts.
We used to rebuild headstacks, and built a jig to do it with high accuracy, probably refurb'd 1,000 of them and we were repairing 5,000 ADATs a year back when they were still available. In fact we took over the factory service so everything shipped to Alesis in the last 2 years of their operation was put on a pallet and trucked up to Northern California to us.

[HSLand]

I figured it was something like that. The whole thing is immaculate otherwise. It still plays audio and I can hear it clearly in some parts, but there's still the constant error 7. I guess it's probably best to just buy another.

Did Alesis ever rectify these issues on XT machines? It's almost like every single one of them is eventually going to die suddenly.

[Jazz P Bass]

Grasping at straws but have you tried to reinitialze the software?

"re-initialize the software by holding down RECORD
and PLAY buttons while turning on the POWER switch."

[HSLand]

Grasping at straws but have you tried to reinitialze the software?

"re-initialize the software by holding down RECORD
and PLAY buttons while turning on the POWER switch."

Yep, doesn't help.

[km6xz]

Every piece of digital gear dies suddenly and parts are not available but the XT was actually pretty reliable. The first model, the Black Face, was introduced and ended up with many field modifications, each upgrade was paid for by Alesis to be upgraded. There were over a dozen mods to be done to them during and a bit after its production run. But they were $3,000 each originally. Considering the time, 24 tracks of digital tape for only $12,000 was an absolute bargain. My Sony PCM-3324 DASH format deck was $125,000 and the remote control was $19,000 back when a hundred $K was real money. That kicked off the second and more serious home and project studio fad. It was a groundbreaking device and it had some really ingenious technology in it, the optical port is still used in modern gear for example. Later Tascam brought out a DA-88 that was about $4,000 that was basically a Hi8 transport with 4 multiplexed stereo DAT channels that was not as technically advanced but better made. Some well known albums were done on both.
A lot of beginning engineers got their starts in their bedrooms on a rack of ADATs and a Mackie 8Bus 24 or 32 input board. It still took some chops and skill to do something of value so most people faded out of the scene. The advent of digital which made recording seem simple and affordable coincided with the demise of the major label record industry from self inflicted damage in the 90s(way before MP3 which the clueless record companies claimed was responsible for their tanking). The record industry died because the success in the 80s meant the companies were all ripe for corporate raiding. By 1990 all the majors were owned by large corporations who thought MBa's and lawyers belonged in the CEO positions instead of the self taught music people who had done very well for 60 years. Within a couple years the newcomers killed the industry, killed radio and killed touring. That is why every town with a radio station only has two choices, right wing talk radio and right wing hate radio. Musicians never recovered. ADATs were enabling technology that came just too late by a year or two from ever transforming music that people actually could hear and buy. Later, when computer music took over, and it was dirt cheap to record, the results were of no value at all.

Regarding the XT and LX, and M20, they worked pretty good but people using them were not used to the requirements of having equipment maintained and serviced so they seemed to die but were really pretty simple to keep running if you caught problems before it stopped a session. They were electromechanical so needed to be cared for occasionally but the very amateur amateurs who were buying them had no experience with gear that needed maintenance.
For studios they were a god-send, with very little maintenance compared to their tape decks. Even the best RtR 2 inch decks like Studer and ATR Ampex needed some attention every time a reel was put on them. A full meter, repro, sync and record alignment plus dolby cal even if the deck was mechanically perfect. Most of the people who bought ADATs had never seen a tape deck let alone being involved with keeping studio gear in proper condition so had no basis for comparison for reliability of performance.
I liked the ADATs, and the DA-88s, both were money makers for me but also I liked the ground breaking technology. They were easy to repair and few took more than 1 hour. We had a flat rate of $65 for repair for other shops and to Alesis so they came by the truck loads. Alesis said we did more ADATs than anyone in the world including the factory. They had a service seminar event every year at NAMM where the shops and techs from all over the world came for tech training and learning about new models or tech issues. They started giving an award for the best support shop world wide and retired it at the 7th year because we won every year but once.
The last one I took my shop out of the competition because others were thinking it was a joke. So that's some of the reasons I liked them and still think a quality record could be done on them that would be competitive with anything produced in the last 50 years. A good producer, with good material would have no problem with Grammy nominations or major project sales on a trio of ADATs. It never was the gear anyway but if amateurs knew that they would buy everything that came out. Them thinking that creativity and chops could be skipped if the right gear was purchased was the main driving force in pro audio equipment sales. Same with guitar amps and effects. Amateurs are much more concerned about gear and "tone" than masters.

[HSLand]

I once owned a blackface that had well over 1000 hours on the heads. It looked like a grenade went off next to it and it was so bent up it wouldn't even fit into my rack without some rubber mallet and plier treatment. It ran beautifully.

Hopefully I'll have some XTs that do the same.

[HSLand]

Would anyone happen to have a copy of the XT service manual?

I'm also still wondering about the head preamp chip. If that chip happens to fail, will the entire unit basically be unusable? Because I've still got mine 'working' -- I still get audio coming out (just glitchy), but with a constant Error 7. If the chip failure results in not being able to read anything at all, I know that that isn't the problem.

[km6xz]

The chip is two video amplifiers with balanced line in. The normal failure mode is one of the two video amplifiers dies. No signal is being read from the tape for 1/2 the head rotation. The error correction is pretty good, since you can still get some usable frames even though half the data is missing.
Unless you have a calibration tape(back when Alesis was still Alesis, they sold the tape for $200 which was cheap for calibration tapes.) be sure not to make any mechanical adjustments. The special tape was a a trackless signal that allowed PG and Envelope alignment.

I am sure there service manuals floating around but all mine are in binders for each model, in storage 7,000 miles away.

[HSLand]

Alright, I acquired an old ADAT from someone and the heads have lots of hours. It's completely fine though. I'm guessing that switching out that burnt chip or switching the heads out completely is probably beyond my ability due to the calibration and special tools that I'd need. Correct me if I'm wrong though.

Thanks for all the help in any case

[oc disorder]

Just thought I would add this

Studio Connections - Home

to the thread .. (respected tech .. serviced Alberts Studios Easybeats etc recorded there Australian band)

[km6xz]

The head is a different part number for the "vintage" blackface and the XT/XT20/Lx20 series/


Regarding digital electronics being through away, that is pretty much true. Caps can be changed but so many manufacturers relied on single source parts that the number of units that can be repaired is based on how many junker parts units can be stockpiled. When buying digital gear, do not assume it has resale value or is repairable, if you can't get the full value from it during its warranty period, it is a risky investment. Manufacturers are so concerned with cost they ignore life of a product and consumers have proven them right 100% of the time. Sell something that has more features and drop the price compared to prior models and it will sell even if there is no repair possible for it. I had a good client come with a box full of wireless mics and rack mount receivers for a concert hall a week ago and finally was able to get information from the manufacturer about the needed parts for repair. NLA, No longer available. The customer said they paid $8,000 for the system just 4 years ago. I suggested he either buy replacements that are the cheapest plastic junk he can find and toss them when they break and he will be far better off than investing in "quality" and losing its total investment in a few years. Or scour eBay and buy up all the junker units for parts and we might be able to keep a few going. I have all the RF test instruments for wireless, a service monitor that cost me $28,000 in 1986 back when $28,000 was real money. That was a long term investment and Motorola supported it with parts until recently. That does not work anymore. Buy cheap and replace often but don't be surprised that the lightest weight devices are probably more reliable than the more ruggedly built 5 years ago.
Recording gear is one example of built in obsolescence because the industry changes formats so often. The ADAT might not fit into current systems but if you built a self contained studio with a stack of used ADATs or DA-88s, a BRC and a couple spare junkers for parts, and a repairable analog board you could do just as good as any other period in recording standards. But to make any recording investment, either it has to be a serious hobby with no expectations of paying for itself, or it better have a short definite payback path or it is just an expensive money losing hobby. If you have reliable paying customers you are ahead of 95% of the others trying to earn a living from recording.

[j-man]

deleted

[jantoman]

Wow. So much time passed since your last post, Km6xz. I really hope you're still reading and writing in this forum, some hint from you would be helpful. Any other help would be more than welcome, of course
I've been working for years in recording studios, starting in 1987 as maintenance engineer, and I fully agree with your words about recording technology. It's such a shame that so much knowledge got lost in recent years: here in Italy only a few studios remain alive, most of them acquired by producers/musicians for their projects.
Back in the days I was taking care of analog Studer machines: when ADATs came out I already quit working in the tech department and became a full-time musician and producer, so I used them a lot but I never put my hands inside (apart for some cleaning).
Last year I "inherited" three XTs: the first one was working fine (almost), the other two had many issues. I managed to fix some (electronic is still my main hobby) but there's plenty of work to do to put them in working order. I found out that two reel motors are completely worn out and should be replaced: I opened them up and clean them, but they're still noisy, hardened and barely spinning, compared to the one that works fine. They seem quite hard to find, though: any suggestion?
The other issue is a "no good tc" message on ADAT #2. I did the ordinary maintenance routine, to no avail: then I plugged the transport to another board using connector extenders - like I used to do with old mixing consoles - and... surprise, it started to read the tapes flawlessly. So I thought the fault was on the board... but then I read that this issue could be caused by PG delay malfunction, correct?
I checked out all three ADAT's PG values (test mode #3) and they're matching with the ones written on the stickers, so now I'm getting a bit confused... could it go out of alignment by itself?
My Hameg HM205-3 scope has a 20 Mhz bandwith: is it enough to read the waveforms?
Thanks in advance.