TP-028, Nat Adderley's Work Song is now available

Author Topic: Studer Head Mod for 1/4 Trk  (Read 8096 times)

Offline Teeg

  • Full Member
  • ***
  • Posts: 73
    • View Profile
Studer Head Mod for 1/4 Trk
« on: March 13, 2011, 06:37:50 PM »
  I've wanted to do this for quite some time...add 1/4 track capability to my Studer A80 VU MKII. The machine handles tape so well it seemed like a good candidate for the conversion. That, along with its ability to handle almost any type of reel in both IEC/NAB would make it a nice playback rig with the addition of the extra head.

  John French and I talked about the mod, which would require removing the record head and installing the new unit in its place. A switch on the top of the headblock would select between 1/4 ~ 2 track. Since the machine was already apart due to a ticking noise coming from the capstan, it seemed like a good time to go ahead with the conversion.

  John turned the unit around in just a few weeks, complete with selector switch, new Flux Magnetics 1/4 trk playback head, and of course he gave the head assembly a good cleaning and lapped the two-track head. Unfortunately I can't give a listening impression as my capstan motor is on its way to Athan for a rebuild. More to follow, but just wanted to share the excitement....

TJ


https://sites.google.com/site/twotracktape/_/rsrc/1300061587861/temp/headblock1.JPG





https://sites.google.com/site/twotracktape/_/rsrc/1300061587861/temp/headblock2.JPG
« Last Edit: March 14, 2011, 07:41:10 AM by Teeg »
T.j. Bassi  
    Martin Logan reQuests....Martin Logan Descent x 2....Atma-Sphere MA1 OTL amplification....Krell KPS25s digital front end....VPI Scoutmaster....Studer A80 VU MKII....Ampex 300-2 Tube/SS Playback "Ampexius Maximus"....Ampex MR-70

Offline kipdent

  • Full Member
  • ***
  • Posts: 49
    • View Profile
Re: Studer Head Mod for 1/4 Trk
« Reply #1 on: March 13, 2011, 08:00:36 PM »
That is really cool! Everything looks neat and clean, too. Congratulations on creating an even more flexible tape machine!
Kip Peterson
Vintage-centric system with Apogee Acoustics Scintilla ribbon loudspeakers, Micro Seiki RX-5000 turntable and other odd bits of tube and solid state gear. Now a proud owner of a Studer A80 RC Mk II tape machine!

Offline Teeg

  • Full Member
  • ***
  • Posts: 73
    • View Profile
Re: Studer Head Mod for 1/4 Trk
« Reply #2 on: March 13, 2011, 09:25:32 PM »
 Are my pictures showing up? I saw them on preview but not after posting...

Tj
T.j. Bassi  
    Martin Logan reQuests....Martin Logan Descent x 2....Atma-Sphere MA1 OTL amplification....Krell KPS25s digital front end....VPI Scoutmaster....Studer A80 VU MKII....Ampex 300-2 Tube/SS Playback "Ampexius Maximus"....Ampex MR-70

Offline Ki Choi

  • Sr. Member
  • ****
  • Posts: 314
    • View Profile
Re: Studer Head Mod for 1/4 Trk
« Reply #3 on: March 13, 2011, 10:35:19 PM »
Hi TJ:

Can't see your photos...;-(

I trust John had put in proper Flux Magnetic Extended Frequency 1/4 track repro head.  The A80VU Mk II has factory repro head with ~10mH inductance and if the new head has different inductance value such as A80RC Mk II's repro head with ~200mH, there will be issues sharing same repro circuit with the original A80VU Mk II two track head.

Ki
Ki Choi

Offline kipdent

  • Full Member
  • ***
  • Posts: 49
    • View Profile
Re: Studer Head Mod for 1/4 Trk
« Reply #4 on: March 14, 2011, 06:48:57 AM »
Are my pictures showing up? I saw them on preview but not after posting...

Tj

I could not see your picture(s) in the post, but if you right-click on the placeholder (control-click on my Mac), and choose "Open image in New Window," the photo displays. I'm not sure why this is happening but at least you can see it!
Kip Peterson
Vintage-centric system with Apogee Acoustics Scintilla ribbon loudspeakers, Micro Seiki RX-5000 turntable and other odd bits of tube and solid state gear. Now a proud owner of a Studer A80 RC Mk II tape machine!

Offline Teeg

  • Full Member
  • ***
  • Posts: 73
    • View Profile
Re: Studer Head Mod for 1/4 Trk
« Reply #5 on: March 14, 2011, 09:23:11 AM »
  Sorry about that, guys. For whatever reason photos stored at my freebie Google site only link if I am logged into the site. A link to the photo URL does seem to work, however. I replaced the photos with links to the same.

 Ki- John took measurements from my existing two-track head before ordering up the 1/4 trk unit, approx 11 mH each track. From what I gathered this mod is done on more RCs than VUs.

TJ
T.j. Bassi  
    Martin Logan reQuests....Martin Logan Descent x 2....Atma-Sphere MA1 OTL amplification....Krell KPS25s digital front end....VPI Scoutmaster....Studer A80 VU MKII....Ampex 300-2 Tube/SS Playback "Ampexius Maximus"....Ampex MR-70

Offline ironbut

  • Global Moderator
  • leader in spreading disinformation
  • *****
  • Posts: 2503
  • rs1500>repro amp#1
    • View Profile
Re: Studer Head Mod for 1/4 Trk
« Reply #6 on: March 14, 2011, 12:52:23 PM »
Thanks Teeg,.. even I can see them now! (heck, I couldn't even see the placeholders before)
JFR does some really nice work huh?
steve koto
 Sony scd 777es(R. Kern mods)> Vpi Aires>Dynavector XX-2mkll>Bent mu>CAT ultimate>CJ premeir 140>Magnepan 1.6qr(Jensen xover)Headphone Eddie Current Zana Deux>AT ad2000,HD800 ,Metric Halo ULN-2 (battery powered),
 HE Audio Jades

Offline jdza

  • Jr. Member
  • **
  • Posts: 10
    • View Profile
Re: Studer Head Mod for 1/4 Trk
« Reply #7 on: March 14, 2011, 01:12:43 PM »
I have done something similar with an A80R. Instead of a switch I installed a second rack of electronics for the  FM 1/4 track head, It is really amazing how good commercial 1/4 track releases can sound- certainly a million miles away from my Revox machines


Johan Dreyer

Offline c1ferrari

  • Full Member
  • ***
  • Posts: 167
    • View Profile
Re: Studer Head Mod for 1/4 Trk
« Reply #8 on: March 14, 2011, 08:38:15 PM »
Looks nice, TJ :-)
Sam Lucero
SPQCV
:-)

Offline Teeg

  • Full Member
  • ***
  • Posts: 73
    • View Profile
Re: Studer Head Mod for 1/4 Trk
« Reply #9 on: March 14, 2011, 08:50:06 PM »
Thanks Teeg,.. even I can see them now! (heck, I couldn't even see the placeholders before)
JFR does some really nice work huh?

  I like to tinker with my tape machines as much as anyone else around here, but when it comes to head work it's best to put the job in the hands of someone who can get it done correctly. Not only does JRF do great work, but if you ever have to just pick up the phone and talk to them, they're really good folks.

Tj
T.j. Bassi  
    Martin Logan reQuests....Martin Logan Descent x 2....Atma-Sphere MA1 OTL amplification....Krell KPS25s digital front end....VPI Scoutmaster....Studer A80 VU MKII....Ampex 300-2 Tube/SS Playback "Ampexius Maximus"....Ampex MR-70