Need help with Pioneer RT707 Recording level very low

K

kevman

New member
Hi,

I got an old dirty RT707 seems to work good, plays fine, and get input signals from any source ok, if I listen to the source with the headphones the levels are good both meters work great. When I record though, it records really really low, way lower then the source is plays back. dont even see a blip on the meeters Any ideas ? The heads seem to look pretty clean

Thanks
 
Just checking, is the tape threaded the right way up? Generally you have a matt-black side and a shiny brown side. The shiny brown side must go against the heads or it will do exactly what you've just described.
 
I tried a few different tapes, and I am pretty sure they were threaded the correct way. I was using a line out from my computer into the record inputes on the back of the unit and also tried old microphone. any other ideas? the meters show no activity when listned to the tape as it records and the volume is really low. but it is normal when I listen to the source.
 
I'm not that familiar with the 707. I do have the big brother (rt-909) and might have a few ideas. Is the bias and noise reduction set properly? Are you adjusting the input with the "line in" control for the inputs in back and the "mic" control if using the 1/4" jacks in front? Is the tape wound with the incorrect side up? Are the rubber pinch rollers getting sticky? It seems the Pioneer RT series decks were notorious for this, seeing as how the rubber produced then wasn't cured properly. A good head demag and cleaning might do wonders.

I've noticed that anything recorded on mine isn't quite as crisp as I would like it to be. The recordings sound kind of flat. However, when I play a reel which was recorded using my Akai deck, it sounds awesome. As soon as I get a good demag unit I will see what difference it makes.

Sorry if I confused you or overwhelmed you. Just wanted to throw a few things out there that you may (or may not have) thought about. Good luck and let me know what you find out.;)
 
The RT707 is a fine machine. They were sought after audiophile decks when they came out.

Properly set up you shouldnt be able to tell the difference in level or tonal quality. With the meters not even registering it sounds like what's already been said: Tape inside out, heads dirty.

A sticky shed tape (eg: Ampex 406/407etc) can make a real mess of the heads. Getting that stuff off can take some time. I'd suggest you stick the machine on its back, get in a good strong light and look carefully at that tape path with a magnifier.
Watch the tape as it runs over the heads. Make sure it stays right in the centre and doesnt creep up or down the capstan shaft. The heads should be really clean and like a mirror where the tape touches them.

BTW the left hand roller is not a pinch roller but just a guide made out of hard plastic. Also the machine does play in both directions but only records in forward.

Cheers Tim
 
Thanks all. Jjones, I adjusted the proper knobs in the front to no avail. it does go up and down as i adjust it , but its overall pretty low. How do I adjust the bias ? other then the heads, is there anything else I can check? I'll take a look tonight at the heads on the heavy beast.
 
Key Kevman, probably the best bet in getting your problem solved would be to head over to the Yahoo group for reel to reel decks. There are lots of knowledgeable people on there to lend a hand. Like I said, I'm not familiar with the RT-707...............yet. I plan on buying one in the not too distant future so I can leave the heavy work (strictly 10.5" reels) to the 909, and the 7"/5" reels for the 707.

http://tech.groups.yahoo.com/group/reeltoreel/
 
Thanks all, I'm gonna give it a shot in the other group, I've just about had it with this thing!
 
Don't give up on it Kev. Like Tim said, the 707 is a fine piece of machinery. Just have some patience. The solution may be simple. I've had to nurse my decks back to health and I've still got 2 more to bring back from the dead.

As far as responses on the Yahoo group, be patient with the guys. Sometimes it takes 'em a little while to respond (possibly a day or two).:p;)
 
check line in level

You could get a mini sterio jack to RcA jack adaptor at Radio shack or some other such place (assuming that you don't have one) and plug it onto your computers line out. Then you could down load one of the signal generator programs that you can google for. Then you set the signal generator to generate a 1 kHz tone and adjust the level until you measure 0.316 volts AC on the RCA jacks (beg, borrow or buy a voltmeter).

The 0.316 volts represents -10 dBv and is a common 0 VU level.

Now that you have a 0 VU signal to feed your deck hook the RCA jacks up to the line inputs. When you select source your meters should read something close to 0 VU. If so then try recording the tome for 30 seconds or so. Then rewind and play it back. You should also get a reading of near 0 VU. (Don't forget to select playback)

There may be input selectors to select mic or line and input level controls to adjust the input levels (duh?) that you may have to adjust.

My hope is that you are lightyears ahead of this belated post and don't need it.

If you cannot 0 VU in the source position then the signal is not getting into your deck properly (so to speak). If you ger a near 0 VU reading on source but not on playback I would first make sure that the record head is very clean.

There are other tests are useful (monitor from playback head during record for example).

The basic idea is to take the signal chain and divide it in to 2 to see which side is failing. Once you have the failure point identified the solution should appear. (Poof of orange smoke drifts away after a small flash and bang appear over your head)

Don't give up and best of luck.

PS a service manual is always nice to have.

--Ethan
 
The point made about the heads being immaculately clean can not be overstated enough. Even a small baked on layer of oxide, deposited from a previous roll of sticky shed syndrome tape can be enough to throw your levels way off when attempting to record.

Skip the normal route of isopropyl alcohol and go for some methanol instead as that has much more cleaning power to get at really stubborn, ground in oxide. Observe all the safety precautions of using it in a well ventilated environment and keep it away from all sources of flames and sparks as it's highly flammable stuff!

Odds are your problem lays there unless a previous owner has botched up the internal calibration settings of the deck...ask the person you got it from if this is the case and if so, get the deck calibrated by a reputable service shop or buy the calibration tapes, test gear and learn to do it yourself...it's up to you.

Cheers! :)
 
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