Teac A-3440: Difference between revisions

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Tapetech,Yes .the two micro swt's that the tension arm makes contact with.The one that engages the pinch roller was bad.Teac p/n is 51300010.
Tapetech,Yes .the two micro swt's that the tension arm makes contact with.The one that engages the pinch roller was bad.Teac p/n is 51300010.
Hi BeatleFred,
The items in the A3440 that need attention are pots, capstan motor and belt as well as the Pinch Roller Linkage for grease issues. I have had a few electronics failures in the past but I would say that the electronic failures will come more often due to caps than in the past. The changing of a lot of Electrolytic caps by a good technician can not be that hard as the cards pull out the bottom and can very easily be done on the bench. Much easier than an X1000R or A3340S. They should be changed as they are going to be drying up. After 30 years of sitting and power being applied scarcely they can not be that long lasting plus this is not a large investment in parts.
Who knows, in 2 or 3 years the current Electrolytic capacitor might be all gone due to lack of manufacturing and then everyone will be scurrying around trying to find some and end up with the Chinese caps that won't be a plus to use. Nobody sees this better than I on the front line.
Get them done, date the board as to when and move on using a well operating machine.
The RX-9 is a unit that could have problems due to the high use of relays.
The real solution is to use the better DX-4D unit as they do both jobs all the time- the is 4 encoders and 4 decoders all the time. The control cable is not needed in that case as it was for encode and decode switching depending on mode. They (RX-9) are going to be costly to repair as well.
The dBx units are used for NOISE REDUCTION and nothing else. They do not make the music more dynamic and if they do that is because the deck is out of calibration and is showing a double error in the record process. When you use two track you can get away with no noise reduction, when you strat mixing the noise adds up. When you get to 8 tracks you for sure need it. With 4 tracks that can be a matter of opinion and a part of the recording process. I used it in many demos I did and it worked well all the time- then again my machines were well calibrated at the time unlike some peoples' decks that can be far off and the dBx just makes it worse. The FV cable and circuit in the DX-4D can be removed and circuit disabled- I have done a few and there is no need for that cable anymore. The DX-4D can then work just fine as long as the proper nominal levels are put into it.
Output levels and mixer settings. The reason a mixer or tape deck is set at what is called specified output level is that this is a setting which is giving a known output at approximately a 70% gain setting. Most mixers have a grey area on the panel at 70% area. This is put there not to make it pretty but to give indication that this is the unity gain setting of that circuit. The Unity gain setting is one where neither gain or attenuation is used for the signal. Gain adds noise as the signal is too low, attenuation is needed because the signal is too high. Due to power supply rails, it is best to stay inside of the good operating position of the power supply rather than having the decks output at max (again a gain setting) and to allow the deck to put out a sufficient signal without hitting the clipping point or that of exceeding the power supply rails that an Op Amp can handle. In studios I always set my machines up for the specified output position and then leave it there.
Tape pack is one thing that the newer better machines do best. They should all be this way but over time the tape deck makers did not start all of their decks out with the most latest technology. The decks like the Tascam 52 can wind tape with little scatter. The spooling mode packs the tape as if it was just played. The Tascam 42 does the same thing but looses some control over the tape due to the arm configurations. That is why the Omega drive was made and included in the 50 and 60 series decks. All you can do on a A3440 is to use good back coated tape and to make sure the reels you use and TZ612 are in good shape and to try and not get the reel tables damaged. The tension arms need to be kept clean and edges to a minimum and polished. It can make a world of difference like when JRF gets done polishing a head stack, there is no tape handling problem when he is done and the overall performance is enhanced due to it. This does not make the tape pack different but it travels across the heads much better.
Oh, the electrolytic caps should be changed prior to calibration as the better caps will make gain changes. I don't know of anyone who is willingly using 60 year old Electrolytic capacitors in their circuits.
I hope this addressed all the questions you had.

Revision as of 09:29, 28 November 2012

As an A-3440 enthusiast, I'm glad to hear you were able to get the issue resolved, thanks to Sam, he's the man!

I'm just curious if you can check the serial # on the back of yours, which indicates the manufacturing date (the digits on the right side of the s/n). I believe the A-3440 was introduced in '78 (not sure if was the beginning of the year, or more toward later), along with its matching 2A mixer. (My older brother bought one new back in '79, when I was a teenager).

The Tascam 34 came out in '82-'83, but I find it interesting that the A-3440 didnt seem to be discontinued, and was still being made at the same time as the 34. Does anyone recall what the $ price difference between them was?, just curious. I have a collection of Teac/Tascam literature, and it appears that the A-3440 and 2A were still around as late as 1984. Anyone know if the 40-4 made it that far as well?

I was also curious if there were any revisions made to the A-3440 during its production run. Is an '83 A-3440 exactly identical to a '78 model, or are any circuit boards and components, etc different? I know the Model 2 (2A) mixer had a few slight changes- the knob colors and fader controls, and also had the raised meter bridge with faux-wood panels... Just a few lil' details I find interesting, if anyone else might also relate.

Tapetech,Yes .the two micro swt's that the tension arm makes contact with.The one that engages the pinch roller was bad.Teac p/n is 51300010.


Hi BeatleFred, The items in the A3440 that need attention are pots, capstan motor and belt as well as the Pinch Roller Linkage for grease issues. I have had a few electronics failures in the past but I would say that the electronic failures will come more often due to caps than in the past. The changing of a lot of Electrolytic caps by a good technician can not be that hard as the cards pull out the bottom and can very easily be done on the bench. Much easier than an X1000R or A3340S. They should be changed as they are going to be drying up. After 30 years of sitting and power being applied scarcely they can not be that long lasting plus this is not a large investment in parts.

Who knows, in 2 or 3 years the current Electrolytic capacitor might be all gone due to lack of manufacturing and then everyone will be scurrying around trying to find some and end up with the Chinese caps that won't be a plus to use. Nobody sees this better than I on the front line. Get them done, date the board as to when and move on using a well operating machine. The RX-9 is a unit that could have problems due to the high use of relays.

The real solution is to use the better DX-4D unit as they do both jobs all the time- the is 4 encoders and 4 decoders all the time. The control cable is not needed in that case as it was for encode and decode switching depending on mode. They (RX-9) are going to be costly to repair as well. The dBx units are used for NOISE REDUCTION and nothing else. They do not make the music more dynamic and if they do that is because the deck is out of calibration and is showing a double error in the record process. When you use two track you can get away with no noise reduction, when you strat mixing the noise adds up. When you get to 8 tracks you for sure need it. With 4 tracks that can be a matter of opinion and a part of the recording process. I used it in many demos I did and it worked well all the time- then again my machines were well calibrated at the time unlike some peoples' decks that can be far off and the dBx just makes it worse. The FV cable and circuit in the DX-4D can be removed and circuit disabled- I have done a few and there is no need for that cable anymore. The DX-4D can then work just fine as long as the proper nominal levels are put into it.

Output levels and mixer settings. The reason a mixer or tape deck is set at what is called specified output level is that this is a setting which is giving a known output at approximately a 70% gain setting. Most mixers have a grey area on the panel at 70% area. This is put there not to make it pretty but to give indication that this is the unity gain setting of that circuit. The Unity gain setting is one where neither gain or attenuation is used for the signal. Gain adds noise as the signal is too low, attenuation is needed because the signal is too high. Due to power supply rails, it is best to stay inside of the good operating position of the power supply rather than having the decks output at max (again a gain setting) and to allow the deck to put out a sufficient signal without hitting the clipping point or that of exceeding the power supply rails that an Op Amp can handle. In studios I always set my machines up for the specified output position and then leave it there.

Tape pack is one thing that the newer better machines do best. They should all be this way but over time the tape deck makers did not start all of their decks out with the most latest technology. The decks like the Tascam 52 can wind tape with little scatter. The spooling mode packs the tape as if it was just played. The Tascam 42 does the same thing but looses some control over the tape due to the arm configurations. That is why the Omega drive was made and included in the 50 and 60 series decks. All you can do on a A3440 is to use good back coated tape and to make sure the reels you use and TZ612 are in good shape and to try and not get the reel tables damaged. The tension arms need to be kept clean and edges to a minimum and polished. It can make a world of difference like when JRF gets done polishing a head stack, there is no tape handling problem when he is done and the overall performance is enhanced due to it. This does not make the tape pack different but it travels across the heads much better.

Oh, the electrolytic caps should be changed prior to calibration as the better caps will make gain changes. I don't know of anyone who is willingly using 60 year old Electrolytic capacitors in their circuits.

I hope this addressed all the questions you had.