Akai 747 w/DBX question

barnettk

I was interested in the DBX mainly to get the bump on dynamic range which also by proxy reduces the noise however like I said the faster recording speed definitely improves things for sure. The Dolby A I think would improve the highs.

Dolby ’A’ will improve the highs and DR.

Not really a fan of demagnetization. There are two camps on that topic and it seems to be a little dangerous for me to try it myself even though I do have a demagnetislzer. Your thoughts on that.

I was not aware that there are two camps of thought about demagnetization. There’s no question that tape deck parts can become magnetized with use over time, which is obviously not good for the deck or any tape played on it. Demagnetization is actually part of routine tape deck maintenance. That it can be improperly done doesn’t mean that it should be avoided, imo.

@cleeds  

there are are some that think demagnetizing tape heads is not s good practice. Their words. Not mine. I was just curious to know how he felt about it. So you make a good point. I will never try it “myself” if it gets done it will be part of the bi annual service my deck gets. Good point tho. 

I would suggest demag'ing the heads every so often. Otherwise you will lose high freq response. Just make sure you use a demager with a protective tip and move the demager SLOWLY, you want remove magnetic fields from the heads not add them.

I demag the heads on my decks before doing any serious recording.

The stock load resistors on the 747 are carbon film. you may think the deck is quiet now at 7.5 ips, but wait til you listen to it with Vishays, you'll think you got 30% more musical detail coming through.

The other big benefit the 747 deserves is bypassing the audio stage coupling caps with film and foil caps.

Incidently the Vishays do wonders for MM and MC cart loading positions, but not trying to hi jack the thread.

@johnss 
"Incidently the Vishays do wonders for MM and MC cart loading positions, but not trying to hi jack the thread. "

I am perfectly fine with talking about whatever so it all fits IMO. 

I think these are all good ideas, and the more I think about it I would rather make the deck sound better nativily without adding additional components. Sounds like a better option to me. I was considering re-capping it anyway. So I will see how much my tech will charge me to get that done (adding the Vishays, and replacing the caps. 

Question 1: In regards to replacing  the wire from the head to the PCB with Mogami Console wire. What will this do for me? allow me to add the Dolby A since the ones I have seen have what appears to be a console connector instead of line level?? I have never heard of doing  this so excuse my ignorance on that. 

Question 2: In regards to head demagnetization. Do I need to damag the erase head or only the playback and record heads? I have a demagnetizer, and the way I did it was as follows: Start about 6 feet out and slowly work my way to the head (without touching it) then slowly work my way back away from the head. The first time I attempted this I just got nervous because the closer I got to the head the device seemed to vibrate in a way that, well frankly scared me. Plus its a time consuming process and it was getting pretty warm.. I guess thats normal but I was just afraid I could possibly do some damage to the deck, by  possibly causing some harm to the machines other parts, boards, etc. 

I hope you weren’t using a bulk tape eraser. Those are way too powerful to demagnetize a tape deck, and have pretty short duty cycles