Monday, August 1, 2011

Late model Quad 303 (3rd unit)

I managed to purchase a Quad 303 with a IEC power socket and the large capacitors facing upwards. Such units were produced between 1980-1985.

So far, have not tested the usability of the unit as I need to take out the Quad 33 to partner it. It does power up and the heatsink does warm up after left power for a few minutes.

Thus I decided to open up the unit to view it's state.

Before clean-up
After cleanup

Before cleanup the layer of dust was about 2-3mm with a few feathers in the unit??? Had to remove the heatsinks to vacuum the boards. Rest of the unit was dusty enough.

Capacitor tops after vacuuming

When tested, the unit works fine without issues.


  1. Hi,

    First of all I'd like to say: thank you for your blog, it is always great to read it! These old stuffs are wonderfull!

    I have a vintage amplifier: TEAC BX-300 in great condition. Could you please tell me some opinion and give advise how to tuning it? Thank you.


  2. Hi Indy,


    Apologies as I had not been fortunate to came across this model. As such I have no idea what needs to be improved.

    I did note there were some comments on DIYAUDIO for the BX-300. However, there were no followups.

    What I normally do is go thru some reference material and listen for any reproduction issues, obtain the schematics or trace the signal path on the motherboard (lotsa work) to determine if there are any components which provide good ROI.

    Quality and make of components do effect the resultant reproduction, and, can be highly subjective - as well as how deep you pocket can be!