For whatever it is worth, here is a brief description of typical tape head adjustments: Wrap = twist the head on it's axis, as looked at from above Azimuth = the angle of the head ad looked at from directly in front of the head Zenith = the angle of the face of the head as looked at from above ( that is, is the bottom of the head parallel with the top of the head, or is the bottom 'sticking ' out further or less than the top of the head....? This is simplistic in description at the very least, but may help you. All / any of these adjustments, it incorrect, will make for very poor sound. An expert is really required to do them correctly, and special tools are a requirement. -----Original Message----- From: Association for Recorded Sound Discussion List [mailto:[log in to unmask]] On Behalf Of Paul Tyler Sent: Saturday, April 07, 2007 9:24 PM To: [log in to unmask] Subject: Re: [ARSCLIST] Need help with a Revox A77 [?] in Chicago That's a good suggestion. Paul David Lennick <[log in to unmask]> wrote: Have you tried recording new material on this machine? See if you get the same effect on playback (assuming you have tape on which to record..maybe a blank spot at the end of one of your reels). dl Scott Phillips wrote: > This is part of the mechanical alignment of the heads, and can easily > produce the symptom you describe. It refers to the 'tilt' of the > heads, left to right so to speak, of the heads as you face them. That > is, as you face them the heads are supposed to have their 'gaps' > perpendicular to the direction of tape travel. This is normally set > with a MRL or STL alignment test tape with a phase meter or more > properly (IMHO) with a o'scope. For 'special' reasons it can me > deliberately misaligned to match a tape made on a misaligned machine. > > I'm likely not explaining this well.... As is common with someone who > has done it for so long... :>) > > -----Original Message----- > From: Association for Recorded Sound Discussion List > [mailto:[log in to unmask]] On Behalf Of Paul Tyler > Sent: Saturday, April 07, 2007 3:28 PM > To: [log in to unmask] > Subject: Re: [ARSCLIST] Need help with a Revox A77 [?] in Chicago > > Ah, there's another word of which I was ignorant. Is the azimuth > related to the alignment? Could that be why one of the channels is > way muddier than the other? > > Thanks > Paul > > phillip holmes wrote: Paul, Could be the playback head's azimuth was > mis-adjusted (?). > Phillip > > Paul Tyler wrote: >> Hello, >> >> I'm hoping someone can help an electronic ignoramus. Here's the > story. I have a hundred and fifty open reel tapes I recorded twenty > five years ago that I've been trying to digitize. Most are field > recordings I made on a Nagra on loan from the American Folklife Center > or on a Revox B77 (I'm unsure of the exact model number) owned by a > then brand new public radio station in Fort Wayne. The restof the > tapes are the 26 one-hour radio shows I produced using my field > recordings. After that gig ran it's course, I was left with the tapes > and no machine. The original field recordings are in the Archives of > Traditional Music at Indiana University, and what I have are earliest > copies dubbed on the ATM's Ampex decks. >> Fast forward twenty years and I bought a Revox A77 on eBay and >> started > dubbing my field tapes in my spare time. Somewhere along the way my > preschool daughter filched a light bulb out the Revox--I don't know > what you call it but it was for a light activated shutoff. I took the > Revox to 20th Century Stereo on the north side. The elderly > European-accented proprietor ended doing $300 worth of repairs and > adjustments. This was two years ago, and I'm just now getting back to dubbing my tapes. >> But they don't sound the same. I don't have the technical vocabulary > to describe the sound difference. The clarity is gone. It sounds > like my recordings have gone through some sort of filter that > distances the sound. Another description: >> the loss of clarity sounds like what happens when you dub cassettes >> on > cheap portable decks from 1980. >> Can anybody offer any help? Like what kind of words I should use if > I take it back to the old German guy. Or do you know any other good > repairman (or woman) in the Chicago area I could consult. >> Thank you >> Paul Tyler >> >> >> > >