Re: [ARSCLIST] Need help with a Revox A77 [?] in Chicago

[Scott Phillips <scottp@xxxxxxxxxxxxxxxxxxx>]

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:ARSCLIST@xxxxxxx] On Behalf Of Paul Tyler
Sent: Saturday, April 07, 2007 9:24 PM
To: ARSCLIST@xxxxxxxxxxxxxxxx
Subject: Re: [ARSCLIST] Need help with a Revox A77 [?] in Chicago

That's a good suggestion.
  Paul

David Lennick <dlennick@xxxxxxxxxxxx> 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:ARSCLIST@xxxxxxx] On Behalf Of Paul Tyler
> Sent: Saturday, April 07, 2007 3:28 PM
> To: ARSCLIST@xxxxxxxxxxxxxxxx
> 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
>>
>>
>>   
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