We revised Eduardo's 405.
He uses it in his studio to monitor his recordings.
We used the Dada dual-mono power supply and Burr Brown OPA627 opamps.
"Received my Quad 405 with your upgrade plus the Velleman K4700 loudspeaker protection.
The packing was very secure, well done!
The sound now is much more open and extended; bass to trebles through the whole spectrum are very clear and rich. A very wonderful sound. I'm very very happy . I now can hear very clear my mixing and recording work in much more detail.
Thank you very much for all you wonderful and professional work - I have no hesitation in highly recommending your upgrade services and give you 10/10.
Best wishes to you all (I'm definitely a happy customer)."
Click on the picture to visit Eduardo's website.