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33 ultimate


Quad 33 Full Component Replacement  Service 33FCRS1 @ 250.00

If you opt for this more expensive option, all the resistors capacitors and semiconductors throughout your Quad 33 will be replaced with modern low noise high quality components. If the bare PCBs, slot in cards, sockets, switches, fuse, pots, transformer and the PCB boards are in good condition they will be reused. If any fail our test, we will inform you before going ahead with any work.

We suggest you  only go for this option if your Quad 33 is in physically good condition. e.g., good paintwork, push button switches functioning correctly, edge contacts undamaged, case  intact.  If you are unsure we will check for free (you are of course responsible for the cost of delivery and return).

All the Rs & Cs are replaced on the motherboard too!

What we do:

After verifying that your 33 'parts to keep' are  in good condition (we inform you if any are not); we strip all the existing components from the seven PCB boards.*  We then clean off the solder and flux residue and re-populate each board with new high quality components. For example, the resistors are 1% metal film types. This allows the DC operating points and gain setting components to be optimised and reduces the inherent noise and improves reliability.  Likewise for the capacitors and semiconductors.

The legend light is modified to a white diffused LED circuit. This gives a pleasing clean looking legend. If you prefer the original 'dull lamp orange' we can fit an orange led instead. 

We modify some components in value and rating to improve performance, this includes the PSU smoothing capacitors, rectifiers, bias resistors and response tailoring components. Nothing drastic, just sensible improvements so the system still has the smooth original sound as it was when first unboxed.

The push button switches are individually dismantled, contacts cleaned and reassembled. A similar dismantling action is carried out on the slider pot. If the switched volume control and tone pots are in good working order, we clean the wipers and tracks with IPA. If not, they are replaced with modern nylon spindle controls. The edge connectors are checked for integrity and cleaned.

Everything is then assembled back in place and the system is then checked for correct operation on. Finally a full listening test , PAT and bench soak test is  carried out.   

As you can imagine this is a labour intensive operation but the end result makes the increased outlay very worthwhile.


If your old 33 PCB boards are damaged, it is obviously pointless for us to remove the old components and fit new ones. Luckily, we can supply new pre-populated replacement PCBs at a nominal extra charge.

The examples in the image opposite are typical examples. The top left PCB has lifted copper edge contacts, after the gold contacts were soldered over by an over keen DIYer ! The fault with the lower left image is obvious. The damage was probably caused in an accident, e.g., transit damage or the 33 being dropped.

The same applies to poor or damaged 'top entry' edge connectors. We can fit replacements if necessary. Currently we do not have a source of new side entry edge connectors for the rear slot in cards. If yours are damaged we can only fit  salvaged ones.  

If you have a 33 and you want it brought up to the best possible working condition with our ultimate full replacement service, sent it to us for appraisal. Alternatively contact Rob on 01905 821737 for technical advice. 

*PSU, Pre amp, L/output, R/output, Disc card, Tape card, Tone motherboard


This option uses a similar replacement procedure to the full through hole component service 33FCRS above but we completely replace the old circuits with modern high performance circuits designed in house. The new PCBs slot straight into the existing slots.  Click here for details.




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Last modified: Monday, 27. April 2015 12:57