TG1000 (4.75cm speed) distorted higher frequencies

[helloradio]

Hi

Even at 4.75 tape speed sound is very pleasant till higher frequencies appear.
All the 'sssssss' become very unpleasant distorted 'shshshshshsh'
Very low recording level does not help, just adds more audible tape noise.
I imagined that higher frequencies will be gently rolled off with max frequency let's say 8khz for this speed and half track.

It is not bias thing and the tape is BASF.
Just wondering if something went bad like capacitors but if yes why other speeds are ok and very nice.

I noticed in the schematics that 10khz is amplified 20dB so maybe recording amplifier and EQ section can not handle this anymore.

Any suggestions from great people willing to help?

Darius

[raimund54]

Hi Darius,

the frequency range of 4,75 cm/s is limited to something around 8 kHz, so higher frequencies are cut off or distorted. The ssss contains a lot of high frequencies and sounds very bad.

Regards,

Raimund

[helloradio]

Hi Raimund and thank you for your answer.
Would you please show me on the schematic which RC elements in recording amplifier are responsible for EQ for 4.75cm speed and to what value to change them to lower from 20dB to 10dB for instance at 10kHz.

Darius

[Hape]

Normally you won't have these kind of problems with a TG1000 at low speed. Therefore to me it sounds like the heads are worn. The recording head is the weakest link in the chain.

Best
Hape