Jump to content

SOLD: Rebuilt Quad 303 Power Amp


Recommended Posts

Need some thump for your La Scalas? The Quad 303 is a two channel power amplifier designed for driving loudspeakers in the 4-16 ohm range and will provide an output of up to 45 watts per channel depending upon the load impedance. The input required for full output is 0.5 vrms unbalanced. Transistor triples are employed in a Peter Walker original circuit to provide a completely symmetrical output stage, quiescent current independent of junction temperature and symmetrical current and voltage limiting. Harmonic and intermodulation distortion products in the audio range are so low that they are difficult to measure in meaningful terms.



Power output: 45 watts per channel into 8Ω (stereo)

Frequency response: 30Hz to 35kHz

Total harmonic distortion: 0.1%

Input sensitivity: 0.5V

Signal to noise ratio: 100dB

Speaker load impedance: 4Ω to 16Ω

Dimensions: 120 x 159 x 324mm

Weight: 8.2kg


This venerable Quad 303 power amp had been rebuilt and upgraded. The case has some small cosmetic nicks on cooling fins, but nothing that detracts or catch your attention.

Work performed: new audio grade Digikey capacitors on all PCBs and power; Nichicon output coupling caps. new Bourns 15 turn trimpots on all three PCBs; regulator, bias, & mid-point voltages adjusted; new AC switch; new gold plated RCA jacks (DIN plug is disconnected and not usable); new IEEC mains input; new rubber feet and a green LED in front for power on.


$450 including shipping in the lower 48. Please email any questions. Thanks.

Quad 5.jpeg

Quad 3.jpeg

Quad 6.jpeg


Quad 2.jpeg

Quad 7.jpeg

  • Like 2
Link to comment
Share on other sites

  • michaelwjones changed the title to SOLD: Rebuilt Quad 303 Power Amp

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Create New...