Some good news (for me??)

mamm7215

mamm7215

Member
So this morning I get the cover off my TSR-8 to put on the new capstan belt I just got. Figured I'd Demag it too while I had it apart so I did. But when I got the cover off I noticed a sticker up top on a square thing between the reel motors that says:
Service Date 1/23/2004
Replace cap&both reel motors
Replace belt and pinch roller
Replace reel tables & hubs
Adjust tension pb,ff,rr, lube
Polish heads, clean, demag 90%
Cal bias/eq/dbx for 499

Now I know it's only been used lightly since 2004 and has sat unused since about 2006 before I bought it (for $500.00) so this is basically a completely rebuilt unit, no?
The only thing is I've calibrated it with my MRL tape for 456 (+3) and didn't do anything to the DBX so it's still calibrated for 499. Is this a problem? Should I cal to 499, I have 2 reels of it that don't shed. I know it's harder on the heads and I've got 3 good reels of 456.
And maybe I won't do the belt 'cause it looks like a big job. Anyone done a belt for one of these units?
 
Update, got the belt on...thanks AGAIN Beck, I found you post on how to do it! The belt that was on before was definitely stretched.
 
Wow!

That's really cool!

What is the head wear look like on your TSR-8?

I don't know anything about calibrating the onbooard n/r, so I can't help you with that, but if it were me I'd be setting it up for 456...that's just me tho' being newbie to using the atr...I'm hyper concerned about anything that will accelerate wear on the heads that isn't necessary, and until I have some more experience with the tape for which my 58 was designed (456 equivalent), the risk of increased head wear isn't necessary. If I try the 499 equivalent tape and I like what it can do, then the risk of increased head wear might be worth it.

Hope that helps in some way.

I'll be interested to see what others say.
 
The head wear was light and even. I think I'm going to go through the manual and see if I can just reset the DBX levels to 456. 499 is for +6 and I don't know if I need that, the s/n is negligible as is anyways. These decks were designed for +3 iirc, too.
Cheers.

oops I meant +9, d'uh
 
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This was clarified for me in a recent thread, so this will be a test to see if it finally stuck!

499 is a +9 over 185nwb/m tape. 456 is a +6 over 185nwb/m tape. Tascam's narrow-format 8-track atr's were designed to run the +6 tapes with the deck calibrated to +3 over 185nwb/m, which is 250nwb/m.

The tape spec (+6, +9, etc.) just indicates what the tape can handle before distorting to a certain level. The deck can be set (calibrated) to whatever operating level you wish (+0, +3, +6, +2.5, -0.25, whatever). It all depends on how much of the tape's headroom you want to to utilize, and how much risk you want to take that you're going to distort the tape. Why push the capacity of the tape? Higher signal-to-noise ratio...meaning less discernable hiss. Source material with strong program peaks and/or a wide dynamic range will demand some headroom. Source material that has a more stable level will require less headroom or buffer on the tape.

That's why Tascam spec'ed a +3 operating level on +6 tape. +6 tape was the standard of the day, and calibrating the deck at a +3 operating level gave the operator about 70nwb/m (depending on the reference frequency) headroom before distortion. It was/is a good all-around average operating level that offers a good compromise between tape noise and distortion buffer for most types of program material. What tape you use and what operating level you calibrate the deck to depends on your program material, tolerance for noise, whether or not you use n/r, and how you like to use the tape (i.e. do you like to saturate the tape or keep it clean).

That's why, for the time being, I'm sticking with a +6 tape, and +3 operating level, because that's what the deck was designed for and I'm going to start there and get a reference point.

Regarding calibrating the dbx, I don't know how it is on the TSR-8, but the calibration of my dbx 150x outboard units is simply setting the levels up so that what goes in is the same level as what comes out to and from the deck. There are more complicated calibration procedures, but they are far beyond me and shouldn't have to be messed with unless somebody has been naughty and messed with it. So the kind of noise reduction calibration for the general operator shouldn't be effected by what kind of tape you use or what operating level the deck has been calibrated to. Does that make sense?
 
mamm7215 said:
So this morning I get the cover off my TSR-8 to put on the new capstan belt I just got. Figured I'd Demag it too while I had it apart so I did. But when I got the cover off I noticed a sticker up top on a square thing between the reel motors that says:
Service Date 1/23/2004
Replace cap&both reel motors
Replace belt and pinch roller
Replace reel tables & hubs
Adjust tension pb,ff,rr, lube
Polish heads, clean, demag 90%
Cal bias/eq/dbx for 499

... The only thing is I've calibrated it with my MRL tape for 456 (+3) and didn't do anything to the DBX so it's still calibrated for 499. Is this a problem?
Click to expand...

Wow, a service sticker... you don't see many of those with that much info. It looks like all the major things have been taken care of. 90% head life is good. :)

Yeah, you'll have to do a full level calibration starting with reproduce level and including bias and record level before setting DBX.

You can set bias the traditional way by using the meters, but it’s time consuming with a 2-head deck. I take it you have the manual, so you know how to set the bias by measuring AC voltage across test points 1 and 7. It should read 35 mV for 456. It’s not documented in the manual, but when setting bias for +9 tape it should read 43 mV, so you can check to see if it was in fact setup for the higher bias tape.

If you leave the bias set for 499 while using 456 it will dull the high end. 499 will also increase head wear with long-term use, so I recommend sticking to the factory recommended +6 tape like Quantegy 456 and RMGI 911. The tape tension is a bit different between 456 and 499 as well.
 
Yes I did, thanks. That's what I ended up finding and got it changed out fine. Beck, yes I have a service manual and will do another calibration. The service manual only has a small paragraph about setting the DBX. One is play the MRL tape and punch the DBX in/out at the diff. freq's and make sure there's not more than +/- 1db variance on the output levels. Also record a nominal signal with the dbx in and play the recording back to see if the levels are the same so it appears pretty basic. It's pretty easy to calibrate as my deck's I/O goes right to one of my patch-bays so I just use a test lead from there for all channels.
 
I recommend setting the bias by EAR and VU meter. Find the setting that Sounds the best and calibrate all the channels to that setting. Its really not that hard and performance will only go up. Your tension is now adjusted for 499 potentially so you might want to look at that (does a pro here want to give a tension adjustment superclass???) Also when you replace the motor on one of these tascams it now will not run at exactly 15 ips unless they recalibrated that as well. The only way I know how to do that is by ear and I haven't attempted it on my 32 that had transplant surgery but next time its open if I remember to do it I will. but yeah sounds like you got a sweet machine!
 
So here's another thing I found...I'm going through all my calibrations as per the manual and levels, biases, everything is lining up great. I'm now at the dbx part (last part) and the adjustment pot ISN'T on the edge of the card, it's about 3/4" inside and facing up, not out. Do I need to fab a right-angle screwdriver to adjust this? What a pain and it's the last step. The dbx is definitely calibrated to 499 because when you play a tone and switch it in/out, there's supposed to be not more than 1 db of difference and my levels jump 3-5db so I have to notch it down for 456.
Anyone done this?
 
Yep, that step is a pain. If you don't have a right angle tweaker in your set you'll have to get or make one. You’re using plastic or nylon tweakers, and not metal, right?
 
yes, I got a little set of plastic ones, I guess I can fab one up with a trusty stove element.. :)
Ugh, everything else went so smooth, hopefully this will too. Playing all the tones back on my MRL tape, I've got +3 levels all across the meters with a 2db bump on ch. 1 and 8 when the 50 and 100hz tones come on. Now for the dbx....
 
what voltage reading are you using for the +3 levels? what tape did you decide to use? what are the readings at 10khz? Turning on the dbx might give that response if you are not recording with the dbx on !!! you have to record tones to a blank tape and play it back with dbx on ! it sounds like you might just be getting 1/2 of the process. I am surprised you calibrated the TSR-8! thats some nice work!
 
I calibrated the 8 without DBX in. Should it have been with dbx in? The only reference to turning on the dbx is in the dbx cal section...otherwise I'm measuring 316mv for a -10db reference level. I have a +6 cal tape so I set the repro levels to +3, so at recording levels of 0db on the meters, I should be saturating to +3...no?
 
everything you did sounds correct.

before you go thinking your dbx is off try recording some test tones to a blank tape.
 
I did that first because I sure don't want to adjust anything I don't have to but with dbx in it's 3db louder than not so I guess it was still calibrated for 499. The other thing is the manual says to play a 1k test tone and switch dbx in and out-you should not see more than 1db variance in the level. Adjust as necessary with R76 (decode level). Well, ALL my channels were +3 or so variance with this so I ended up having to turn that pot all the way down for all channels except 7, I got pretty even with dbx on/off.
I'm currently adjusting the next step which is recording with dbx in to get proper level to tape. Record -10db signal, rewind, play back and see what the level is with dbx in/out. Adjust R73 (encode level) to make it as close as possible with the dbx in/out. That's what I'm getting from the manual anyways, so that's what I'm doing now...
 
And another thing, maybe I screwed something up, when I record to the deck, the levels out of my DAW to the deck are plenty high (peak at -6dbfs for this test), the levels on the deck average 0(dbv), peak +3-5 on the TSR-8 led's, playback they show the same levels as record, but the sound is WAAAYYY low out of the deck. Meters on my EMU 1820M input show -30 and I have to crank any volumes I have to max to hear it. Heads are clean and demagged yesterday. I'll have to dig into is some more tomorrow...
 
Nevermind, I got the level thing, It was a routing thing. Patchbays and EMU are confusing. Anyways, levels are all good, sounds almost the same with dbx in or out, just with it out you can really hear the tape hiss and when it's in it's gone, may lose a "hair" of high end but just a different sound is all. I think I got it this time...
 
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