Revox B77 Reel-to-Reel

[337alant]

Hi Richard
All the Manuals for the B77 are here Index of /studer/Public/Products/Revox/Revox_B77 (reeltoreel.nl)
Generally 7.5 ips has a bigger bass hump that also goes lower than 15IPS
I have just calibrated a Tascam BR20 and that was the same
I will try and post some examples when I learn how to use that ARTA ?

Alan

 

[337alant]

Sill had no time on Arta, but just to give you an idea what a typical R2R head bump looks like see my notes sheet below for a Tascam BR20 with LPR90 tape, note the at 7.5ips its still within -3dB at 10hz, 15ips rolls off sharply below 30hz.

IMG_4427 by Alan Towell, on Flickr

Alan

 

[ToTo Man]

Sill had no time on Arta, but just to give you an idea what a typical R2R head bump looks like see my notes sheet below for a Tascam BR20 with LPR90 tape, note the at 7.5ips its still within -3dB at 10hz, 15ips rolls off sharply below 30hz.

IMG_4427 by Alan Towell, on Flickr

Alan

That's interesting Alan. I'm not seeing that behaviour with B77 with the white noise, jazz and electronica tracks I recorded. I get the mid-bass bump in 7.5ips but then it starts rolling off in the low-bass earlier than 15ips. Maybe my B77 is just an exception to the rule?

 

[337alant]

That's interesting Alan. I'm not seeing that behaviour with B77 with the white noise, jazz and electronica tracks I recorded. I get the mid-bass bump in 7.5ips but then it starts rolling off earlier than 15ips. Maybe my B77 is just an exception to the rule?

I don't remember yours being any different to other machines?, I will check my B77 HS tomorrow.
I prefer to use a tone sweep rather than white noise
Here is a video of a FR check on a B77 that I did and it looks looks flat within + or - 1dB, I only started at 100hz so you cant see the bump
Revox B77 Mk2 - YouTube

Alan

 

[Ray Jung]

Hi!

very interesting discussion indeed.

I am also upgarding all boards with better parts.

especailly I need to know 470K trimmer in monitor amplifier PCB.

it has only 2 leg.

From Alan's photo, it looks like one of Phier trimmer.

But I can't find exaxt part no.

would any one specify part No?

Hi,I’m a novice, just bought a Revox B77, what I want to ask is: Do I need to open the machine for visual inspection and lubrication before powering on?
Best regards
Ray

 

[chartz]

Hi,
You should yes. I’d replace the Rifa snubber cap on the power socket first.
Then just check everything runs smoothly, especially the three motors.
I’ve just replaced 4 ball bearings that were knackered.
Then check head wear, which should be under three mm.

 

[Mynamemynaim]

Then check head wear, which should be under three mm.

3mm
Yes I should hope it should!!

 

[chartz]

I have come across ReVox machines with 5 mm large wear print – totally worn. About 2-3 mm is acceptable.
New Revox heads are pretty easy to find but setting up new heads is a real achievement.
I steer clear of worn studio/radio machines. I now have theee mint machines: G36 mk3, A77 mk3 and B77 mk2 (currently under restoration process) all bought from one original owner and practically never used.
I suspect many of those were nice ornaments more than audio sources, because when cassette arrived they became kind of obsolete for many users.

Look at my friend Yves’s complete dismantlement of his B77 – eye candy!

https://www.vintage-audio-heritage.fr/viewtopic.php?f=101&t=10509&hilit=Revox+b77

 

[Avinunca]

Shouldn't this be a 'stickie'? So interesting and lots of useful information.