DX-4D info etc

[evm1024]

Anyone interface a DX-4D to their 32?

I have picked up one and I'm looking for manuals/schematics/info and alignment information.

I have a 32 Manual and a 3440 manual so once I figure out the control pin function I should be able to build an adapter to the 32 and 3440 and who knows what else....

Thanks!

 

[evm1024]

I should note that there are lots of questions about this on seach but no answers (perhaps I missed them) And having the machines here I can get it working....

 

[The Ghost of FM]

You can use the DX-4D on a TASCAM 32, no problems or reconfiguring of the control pins required. Just use the first two channels of the dbx, plug in the control signal cable and you're done.

The levels for calibration on the 32 must be set with the dbx in bypass mode to get 0.317 volts input to show 0vu on the meters with a 1Khz test tone and on repro, get that same 1Khz recorded tone to show the same voltage on your multi-meter. Just trim the record level knobs on the front panel of the 32 to set your levels.

The DX-4D's internal settings, unless monkeyed with by a previous owner, should not need to be touched and is why there are no external calibration controls on the unit because it is supposed to stay set from the original factory set up.

Cheers!

 

[A Reel Person]

I'd swear that...

0vu = 0.316V on a -10dbV spec.

......................

 

[The Ghost of FM]

0vu = 0.316V on a -10dbV spec.

......................

You're right!

I can never remember that damn number!

Thanks Dave!

Cheers!

 

[evm1024]

er make that 0.316 volts

thanks Ghost.... I think that you mean 0.316 volts. I think tht I have enough information to see if I can interface this to my 3440. Should not be too hard but I may need to wire up some logic if the 3440's dolby signal need it.

My 32 manual has enough info to get going. Ans the 3440 schematics will cover the rest.

I do want to learn how to calibrate the internal controls of the DX-4D. I would assume that there has been drift over the last 20 years.

Level adjustment looks very easy. (assumes a properly calibrated deck) Just make sure that 0.316 volts @ 1khz is 0 dB going in and 0 dB going out of the deck is 0.316 volts. This is the reference point of the DBX unit.

No sweat.

 

[The Ghost of FM]

I do want to learn how to calibrate the internal controls of the DX-4D. I would assume that there has been drift over the last 20 years.

I have two DX-4D's on my TASCAM 38 deck and they have stayed true since I got them and mine are also around 20 years old at this point. If there has been drift in them, I think it's pretty negligible and wouldn't worry about that.

Having a well calibrated tape deck is of far more concern and importance because they will slide in their specs because of head wear which forces calibration touch ups to compensate for the wear and the condition and batch of your blank tape media. The electronics in the decks are actually very stable!

dbx drift is the least of your problems.

Cheers!