Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Leevi on January 11, 2020, 02:27:12 am

Title: Distorted output signal
Post by: Leevi on January 11, 2020, 02:27:12 am

I'm working with a 5D2 based amp and wonder the distorted output signal.


https://el34world.com/charts/Schematics/files/Fender/Fender_princeton_5d2_schem.pdf (https://el34world.com/charts/Schematics/files/Fender/Fender_princeton_5d2_schem.pdf)



I made two measurements (see the pics) with same volume (clock 9) and tone (clock 7) settings.


The first measurement (clean) is done on power tube grid before 1.5K  grid stopper (added to the circuit).


The second measurement is done on the output with 8 Ohm load.


Plate voltage: 305V
Cathode voltage: 17.7V
OT: SE OT 5K/8 Ohm


/Leevi

Title: Re: Distorted output signal
Post by: Leevi on January 11, 2020, 03:41:36 am

Found an issue with measurement cables so the situation is not that bad as described.
Some kind of distortion is normal?


/Leevi

Title: Re: Distorted output signal
Post by: shooter on January 11, 2020, 04:06:51 am

Quote

Some kind of distortion is normal?

yup, I believe that amp is played distorted way more than played clean.