Ampex AG-440B-8 Story...

sweetbeats

Reel deep thoughts...
I'm more or less putting this up as a place-holder while the information is fresh in my mind...This came up on eBay. Got it for a pretty good price but it needs help for sure. I'm just in process of doing some coarse cleaning and running an inventory of obvious parts needed before it goes into storage. Not going to touch this much for awhile until some other projects both studio and home-related are finished, and also not until I sell some gear.

So the bottom line is that this thing is pretty straight but it looks like a deck that has been used as a parts deck...some tape path components are missing (scrape-flutter filter, head shields for instance...simple stuff like that :rolleyes:), the monitor head is beat up...pretty much no hope in that one so that stinks...didn't figure that out until I got it home and looked closer...covers are missing to some things, but it looks like it might clean up pretty good. It has the (apparantly) more desirable AC capstan motor and it is a 'B' model which included a lifter delay circuit so the tape wouldn't hit the heads until the transport came to a stop...all the electronics modules are there and are also 'B' variety which had improvements over the 'A' electronics, but there is one repro card missing (each module has three cards, one each for bias, record and repro) from a couple modules, and a couple others that are suspect...shoulda pulled the covers off before driving away...It did come with a new pinch roller, spare relay, a dummy plug and some used tape :eek: so that is good...just need all the stuff that attaches the roller to the arm...:o Anyway, the gentleman I bought it from was really, really nice and has a collection of some of the most wonderfully eclectic and desired vintage gear...wow. So here are some pictures and then it is going away for awhile.


Have to have a picture of the gear in the Subaru...everything fit...barely:
440-8%20in%20a%20ru.JPG



Here it is unloaded, front view:
Front.JPG



And the back view:
Back.JPG



And here are the electronics modules that are obviously not in the rack with the transport...nobody but nobody would be able to safely move that thing with the electronics in it...it was a bear with the rack empty:

Electronics.JPG



The transport:
Transport%20Overview.JPG



And the underside of the transport:
Transport%20Underside%2c%20small.JPG



Headblock:
Head%20Block.JPG



A closeup of the repro head:
Reproduce%20Head.JPG



And a closeup of the sad, sad monitor head...it appears that it sustained a hefty impact. See the crushed laminations on track one, and compare this picture with the one of the repro head and you'll notice that the monitor head looks like it separated from its base and its been hot-glued together :eek: and even the mounting plate looks tweaked:
Monitor%20Head.JPG



And just for fun the erase head:
Erase%20Head.JPG



Power supply unitswoo-hoo:
PSU's.JPG



A bias card...I'm so used to the PCB's in my Teac/Tascam gear...these are so different. Really hefty...thick...and there is so much solder on them; on the traces:
Bias%20Card.JPG


And last but not least I thought this would be fun...here is a Tascam 48 amp card with the equivalent of the "amp card" of the 440, the electronics module:
Old%20School%20and%20'Contemporary'%20Amplifier%20Electronics.JPG



Well, that's all for now! ;)
 
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Seriously, Cory, how does the 440 strike you as far as ease of service and "LEGO", just pull 'em out, components? Thanks for sharing this story with us. :)
 
The Saga multiplies.....

Well Cory, If nothing else those amps go for a pretty penny.

Drop by some weekend (in the spring) and we'll relap those heads.

--Ethan
 
Can they be relapped? The one head shows gaps, if that's the case, I'm pretty sure it's garbage. I don't know how available the headstacks are but man I'd sure like to see that baby reconditioned and working, that'd be one sweet unit...
 
Can they be relapped? The one head shows gaps, if that's the case, I'm pretty sure it's garbage. I don't know how available the headstacks are but man I'd sure like to see that baby reconditioned and working, that'd be one sweet unit...


It won't hurt to try.... And actually if you look at it you can see that the gaps are visible on all tracks and that they are uniform in width. I think that we are seeing the gap spacer here rather than a worn out head. You can also see the gap spacer on the other head.

Regards, Ethan
 
Yeah, I think Ethan is right. I don't see any gaps...it is misleading because of the original profile of the head...the wear pattern is the skinnier band in the middle.

Ethan, I will be in touch with you about relapping. Shared with the folks over on the Ampex List about the results of the lap job on your 38...was it roughly -2 @ 30Hz and -8 @ 34kHz? :eek:

Though I don't think the repro head (what I was calling the monitor head) can be saved with that damage to track 1, but good for practice...:D

Daniel, I'll let you know about the LEGO-esque nature as I get into it more with breaking down the transport and cleaning/testing/repairing, but even just looking at it yeah...everything interconnects with neat plugin harnesses...need to pull the capstan motor? Rotate the transport, remove the motor mount screws, unplug capstan motor harness from the transport control box and its out...everything is that way on this thing, but I have to say that it feels really alien...so used to the Tascam decks...I'm sure I'll get more comfortable, but it is all pretty new...
 
Yeah, Ethan is really good at those lap jobs. He posted photos of the before / afters a while ago and it looked like a brand new head. :)

Cory, just wanna echo a previous statement that I too look forward to that machine being reconditioned and working. IMHO, with Ethan's help, you're most of the way there, as the heads are the costly proposition and Ethan will do a great job, I'm sure. You know, I'm not at all down on that head which appears to have a crushed track one. Don't give up on it yet as I think it can still be re-polished.

Take your time, Cory. Don't rush it. We'll still be here.;)
 
The electronics ("amps") are line-level amplifiers, not microphone preamps.

Daniel, the problem with that record head though is that not only are the laminations crushed on track 1, but the thing was separated from its base and has been glued back together...and it wasn't even glued on straight...I haven't lost hope on that bit, I mean, I'll pull the head at some point and pop it apart, get the glue cleaned out and use a proper thin adhesive to re-glue it, but do you really think that head could ever function right again? It needs more than a polish on track 1...its like the equivalent of taking a ream of paper and smacking the end of the stack with a hammer...the paper sheets in the stack are like the laminations.
 
I've been messing with "modern" equipment too long

heehee

Laughing at myself...I was pondering last night about the different rollers and guides in the tape path and then it hit me..."which one is the tach roller"? Hehehee...then it really hit me "wait...there's...no counter on that thing!"

I'm quickly starting to understand the value of:

  1. razor blade
  2. splicing block
  3. splicing tape
  4. leader tape

heeheehee...
 
I haven't seen the thing up close, but it looks to me like the front of the track has been squished down. If you can use a knife or something to get rid of the squished bit and prevent it from touching the guard, my guess is that a relap could probably save it, though it would likely reduce the total life of the head.
 
I haven't seen the thing up close, but it looks to me like the front of the track has been squished down. If you can use a knife or something to get rid of the squished bit and prevent it from touching the guard, my guess is that a relap could probably save it, though it would likely reduce the total life of the head.

We can measure how far down it is and if it is further than we plan to go on the relap we can dress it up a little, epoxy fill it and then lap over it. So long as the gap is OK, I'm OK.
 
Smoke test

Finished vacuuming up the dust off of it last night and looking a little closer at some things.

Turns out there is a flywheel assembly missing from the Reel Idler (the idler to the left of the headblock) which explains why I can just pull the whole assembly out right now...another 440-8 owner told me that with the flywheel "that thing should spin for several minutes after you rewind tape off the supply reel". I may have a source for one though.

So of course I had to plug the thing in and test the transport functions at least before tucking it away for a bit.

Takeup%20Motor%20Spinning.JPG



All the transport functions seem to be working just fine. Everything will need cleaning and adjusting I'm certain, but lifters lift, reel motors spin, brakes brake, and the capstan motor spins...it even spins really fast if I switch the transport to hi speed...not certain yet if it is setup for 7.5/15ips or 15/30ips, but it spins really fast when set to high speed. Once I get the pinch roller assembly put together I'll measure and dump some tape through to see...might also see if it is easy enough to find where the speed option is set...saw that somewhere but I'm not certain yet if my version required a soldering iron to do the job or if its a jumper setting. I think with my capstan motor it is a solder job...

So that's all for now. It is at least in a more climate protected area now. Now...back to dismantling my parts 48...I've got stuff everywhere.

OH! Here's a video of the smoke test:

YouTube

I must say it seemed too easy to do this smoke test after my last two power up challenges (the M-520 which was missing the PSU at first and then once that was found there was still a missing umbilical cable so that had to be fabricated and of course the parts were obscure, and then the power up of the Tascam M-___ prototype mixer which had no PSU, umbilical cable or schematics to know what was required of the PSU...tackled that with a lot of help particularly from evm1024). This was wierd...I...plugged it in and...flipped the switch...wow.
 
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Man, gotta love the masculine vroom of those motors!:eek::D Makes the 48 / 58 pale in comparison!;) I'm officially jealous, 'cause once restored, this beauty will be amazing. :)
 
jp...I think I've heard that before but never really paid attention because I didn't know what a 440-8 was...or a 440-4/2/1 for that matter. It is naturally of considerable interest now. :) MAN but isn't that getting creative with what you have...I mean, having an 8-track machine at your disposal was a much bigger deal then than now, but doing what they did compositionally without timecode and autolocators, and even moreso without even a tape counter...wow. Reminds me of some of the work Skinny Puppy did with open-reel digital tape machines...:eek:

Daniel, yeah, in the video when I commented that it sounded like it belonged in a machine shop...the whirring and the sound of the brakes just reminded me of a pneumatic cylinder or something...it certainly has an antiquated quality...it turns out that the AC capstan motor is not the more desirable from a performance standpoint...it is easier and cheaper to service, but much more complicated to vary the pitch (not really a concern to me), has lower wow and flutter performance over the DC servo motor, and is susceptible to mains line variations (its speed will vary with line voltage I guess)...but in spite of the vintageness of it it was certainly built at a time when this kind of stuff was just wildly overbuilt and serviceable, so that is really neat. When I look at how my 48 or 58 were built, and then look at some truly contemporary plastic hunk of nothing, that disparity is the same as when I compare the 48 or 58 to the AG-440. I guess that's why it weighs about 350lbs. But there is still a sophistication in the Tascam stuff...I'm taking apart my parts 48 and getting ready to do a sweep of auctions for the parts on eBay and all that stuff is so well-built too...just smaller. :D
 
Cory, I think the speed only varies when 50 / 60 Hz is concerned. That, of course, is not an issue 'cause you're not planning to use it overseas.;)

Years back when I was looking into the AG-440, I was given the impression that the original AC powered design was more rock solid, reliable and indeed easier to service.

--
 
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