Newbie Going analog with a TEAC 80-8.

  • Thread starter Thread starter samth3mancgp
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Here's the thing...you may want to check the record frequency response. Look at page 17 of the Owner's Manual, step 9. Set your oscillator for 18kHz at your reference level (-10dBv or 0.316VAC RMS) and then record the 18kHz tone. While recording monitor off the reproduce head and look at the level on the VU meter. Is it at "0"? If not, adjust R108 until the reproduce level of the 18kHz tone is also about 0VU like the 1kHz was. I ran into this issue with my Tascam 58. I think somebody had whacked the record eq to the point that there was so much HF gain the bias amp wasn't strong enough to bias the tape to handle the signal properly.

The trick is that they go hand in hand so you'll have to do a gross inital adjustment of the record eq, rebias, recheck the record eq, maybe even rebias again.

You need to get a test tape my friend. You realize that all the above is also dependent on your reproduce frequency response. Somebody could have whacked the setting of R102, the "MONITOR EQ" trim pot and you can only set that family of trimmers (R101 ~ 104) with the calibration tape.

You're getting there.
 
cjacek said:
There is a slightly different / add on method, that you can also try. It's from Steve Albini, the original post escapes me now, but here it is:



It's a way to set correct bias for any tape deck. It's basically like dialing in a clean FM radio signal.
Click to expand...

I tried that alternate method of adjusting the bias. The instructions worked very well and I think I did it properly. The 1khz tone peaked out and I adjusted just a TINY bit below where it peaked. I then played a 40hz tone instead of 30 because I could hear it better and made very fine adjustments to bias until I heard little background noise and distortion. If this method does essentially the same thing as the method in the owners and service manual for the 80-8 I like the method using 2 tones better. I am checking the EQ level with the 18khz tone before doing the alternate bias adjustment. (I'm also going to add that after adjusting one channel I saw that it roughly matched all of the other channels that have not been touched for god knows how long. And if the SM911 tape is roughly the same bias as Ampex 456 My adjustment using the other method should be right?)

Correctly me please If I am wrong. Or if the way shown in the service manual is a better idea. I'm going to go ahead and adjust all of the other channels. Also, I'll pick up one of those cheaper test tapes If I know which might be in better condition, or will be more worth the money :) I plan to hold onto this machine for as long as I possibly can. I plan to record quite a bit with it, and hopefully learn a lot in the process. I know I am now!
 
OK, first off, the eBay tapes are likely from the worst period of sticky shed (you know about that) and have the bad binder. If you still want to take the chance, bake the tape (we can provide instructions) so that you can actually use it, provided that the tones are still intact. I would also make an aggressive offer on the tape, perhaps the TEAC one, pointing out the above sticky shed info. Yeah, talk to the seller about it.

Also, you don't have to actually hear the low tones (when fine tuning with 30hz).. You're just adjusting for low distortion / modulation.
 
Haha alright I offered $20 for it. I've been adjusting the EQ and bias for all of the channels. If I play a tone at 10khz and try and adjust rec EQ it does not change anything, and the peak adjust for the higher 18khz didn't seem to do much either. however, around the 10khz range monitor EQ (which I know wasn't one of the adjustments I needed to be making) will pull the 10khz up to 0 VU If it does not reach it. The EQ adjustments all seemed like they were doing nothing. But the bias adjustments using the second method you showed me seemed to work like the instructions.

The position of the bias adjust after ch 2-6 were all pretty much the exact same place. ch 7 and 8 bias position were different than 2-6.

7 and 8 also seemed to have less low frequencies recording. Channel 1 had some very odd issues the higher frequencies were recording very low VU

Just some obvervations I made after the adjustments.
 
OK, now don't take what I say here as gospel but I've been reviewing the rather small and unclear photos of the heads and it seems ("seems" for now) that there's a substantial flat spot on the heads. Now, whether this is a trick of the light is unclear. Say, is it possible for you to take a large, clear, in focus, close up photo of each of the heads, without the use of flash? It is *possible* that the heads are worn to the point that you're having a hard time getting it up to spec.

Another option is for you to evaluate the heads. Take a look at this:
http://www.analogrules.com/badheads.html
 
I have been to that page several times. I read it over and made sure that I knew how to spot a bad head. As of right now I dont think that there are any gaps on the heads, But yes in the picture it looks like they are decently worn, and I would agree. The old Sony TC-377 that I have that dosent work right now because of old caps has almost brand new heads, And It is obvious the TEAC has had some wear. But no Gaps like in that article yet.

I can try and take a more closeup picture today If it have time. Happy Thanksgiving!
 
You said the record eq adjustment didn't do anything while playing back a tone? Exactly. It is the RECORD EQ, not the playback eq. Adjust it WHILE RECORDING the 18kHz tone and monitoring off the repro head.
 
Sorry that was a typo on my part. Or not being specific about what I was saying. It was while I was recording the 18khz tone. and monitoring while it was recording off of the playback head. Both record EQ adjusts seemed to adjust very little if at all :confused:

I think I might try recording some instruments to the new tape with the adjustments I have made so far so I can have a better Idea of what I have done and If it has made a difference. I still dont know what music sounds like on this new tape! :eek:
 
Yeah, record some instruments and post a few photos of the heads, when you have the time.

BTW, can you specify, in bullet form, which things currently remain an issue with the 80-8?
 
Ok The things that remain an issue have drastically reduced since I first started calibrating it. Erase is fine on all channels. All channels record and playback the 1khz tone at 0VU. Channel 1 is no longer dead. 100 times better than when I first started working on it.

Things that remain a problem:
-Channel 6 will not always monitor when in sync mode. It plays back intermittently this has been a problem and remains one ever since I got the deck.

-Setting the bias using the 3dB method dosent seem to be working. I may just be confused by it though and not noticing the peaks and drops. however the other method worked fine.

-Setting the record EQ does not seem to do much on any channels. I think some did more than others. the 18khz tone only got up to 0dB on one or two channels.

-Adjusting the bias, and other levels on channel 1 are very haphazard and different from the adjustments of the other channels. Some of them cannot be performed successfully. (this channel was dead, but started working after I took the card out and cleaned the contacts.)

-I still need to get an alignment tape, the eBay seller did not accept my offer even after explaining sticky shed and how much trouble it would be for me to use the tape every time I needed to run it if the material on it was intact at all :mad:


These are just the problems that remain as of now. I still have not recorded any music to it to test the overall sound yet. I was not told about any of these problems when I first got the deck. I doubt the seller was even aware of them. He didn't even know the difference between the input monitor, sync, and playback switches. I am still happy with my purchase regardless of the problems. I'm having a lot of fun with it and learning a lot too! :)
 
The channel 6 problem may be a sticky relay. I'm not sure how switching works on the 80 series, but it has that kind of symptom.
 
Hmm.. A sticky relay? Are you talking about when I switch from sync mode to playback mode etc?

I tried a little bit of acoustic guitar recording today. channel 1 sounds very weak and kind of muffled. channel 2 and the other inner channels record but with more hissy and ringing noise than before. I didnt get a chance to try any other channels but all of the inner channels probably record well but with the noise too. Probably from adjusting the bias wrong :( as well as who knows what else :confused:
 
Happy to be back to machine that works somewhat decent...

Well.. It's been a while since I have posted on this thread, Or since I have messed with the 80-8 for that matter. I have wasted my time with the old Dokorder I got on eBay when I should have been working on the 80-8.

I took as good of pictures as I could with this Nikon SLR I have. The heads look worn, but I dont see any gaps in them. I have some zoomed in and higher res ones to put up here.

BABAorileylyricsrtf.jpg


Record head.

DSC_2237-1.jpg


Erase head. (this one looks almost new compared to the others?)

DSC_2316.jpg


All three of them.

DSC_2319.jpg


Record and playback heads.



Good or bad? I'm hoping that they are alright for now. = /
 
Yup, looks like some serious wear BUT, BUT..... don't give up on those heads and the 80-8. Yeah, I totally back you up on concentrating your efforts on that beast and not spread yourself too thin with other projects. Take it slow and try to align it and if it still can be done to or close to factory spec then you're still good to go. Maybe a relap down the line.

Can you do the same type of quality shot (for the others) as you did for the erase head? No flash though. BTW, the erase head is usually made of tougher material and its contour is not as critical as the rec / play heads.
 
Yes I can try to get some better photos. It's very hard to do because this camera will not take the picture unless it is a certain distance away
even in macro mode or whatever. I'm going to try to lean the recorder against the wall a bit to get better angles.

I've done a few more test recordings. I think a lot of the noise I heard on the acoustic guitar track was due to my condenser mic. I know they have some "Self noise" of something like that. I accompanied the Acoustic guitar with a 57 on an old peavey amp playing on an Old full hollow body electric guitar made by Aria in the 60s. I heard zero noise on that track. Perhaps it is Biased properly? :)
I need to do more tests though. The rec EQs are definitely still not adjusted. You said this could be because of the heads? I'll add that when I clean the heads. I can tell there is a slight groove right near the edges of the heads from wear. (and probably affecting the frequency response of those channels.)

Lastly, I've been cleaning up the unit (cosmetically) and it looks like there is pollen buildup in the knobs. It's go that orangey, yellowish color to it. Maybe this machine was stored outside for some time before I bought it! :eek:. If it was, I'm grateful for the workmanship on TEAC/Tascam's part. Because It still runs better than any of my others.
 
More Photos!

2.jpg
]

Record head. (without flash)

3.jpg


Record Head and erase head (with flash)

DSC_23202.jpg


Good shot of the playback head

4.jpg


All of the heads.

I thought I might put in a couple of pics of the general state of how my setup is right now. (Obviously not in a serious recording situation ;))

DSC_2326.jpg


80-8 with the nice new reel of RMG! (dont worry I was not trying to clean the heads with that Pledge! :D)

DSC_2328.jpg


The whole analog setup. My monitors are still sitting by my digital rig. You might be able to see them in the pic a bit. Not ideal, but I like it for now.

Soory if the pics are not that big? I saved them MUCH larger than theyare showing up. I think photobucket might be converting them. to a different size.
 
80-8

Ive always considered the 80-8 to be one of the coolest looking Tascam/Teac reel to reels. Mostly because of the cream colored VUs against the black surrounding areas.
 
Yeah, erase head looks fine, sync head looks rough...repro head in between. It all comes down to whether or not you can get it aligned reasonably within spec. Replacement heads are not terribly expensive...saw couple on eBay for $55 BIN. Several decks used compatible heads so they are relatively available if needed, but see what you can do with what you have. My hunch is that it'll work for now.

BTW, you're too modest about your setup...real as it needs to be. what kind of board are you using?
 
Can't really add to what sweets already said. +1 to that.:)

OK, actually, just one thing..... I'd not only keep an eye out for a heads deal but also for another local 80-8, to have as a parts machine. See, I love all the various tape machines that I have but there is plenty reason to have more than one of the same. Stick with the 80-8, a seriously over-built and ballsy sounding deck.
 
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