Possible causes for loss of high frequencies?

[Aerochrome]

I'm currently working on a Pioneer Hipac tape player, and have almost no high frequency sounds being reproduced. Tapes sound fine in another player, speed checks out, adjusted head position, and even bypassed the poweramp to get the line level from the headamp chip (A Mitsubishi M5111, if you have the datasheet please get in touch) and off the headamp chip it still has no high frequency sound. I have recapped the unit, and the only component between the head and the headamp is a tiny ceramic capacitor. Could the M5111 have partially failed?

 

[oldvinyldude]

Head cleaned thoroughly?

 

[Aerochrome]

Head cleaned thoroughly?

Cleaned and Demagnetized.

 

[kfalls]

What do you mean by "adjusted head position"? Have you checked all adjustments azimuth, tracking (height), tilt? Have you looked at the Dolby NR? Taking the hisss out sometimes makes it sound "duller". Does the deck have options for Type 1, Type 2 and Metal tape?

 

[Aerochrome]

What do you mean by "adjusted head position"? Have you checked all adjustments azimuth, tracking (height), tilt? Have you looked at the Dolby NR? Taking the hisss out sometimes makes it sound "duller". Does the deck have options for Type 1, Type 2 and Metal tape?

The Hipac format was in it's "prime" in the very early 1970s, and never had any options for tape formulations or NR.

 

[GPS16]

Hi Guys,

in my case, my age!!!

GPS16