PMS built by Ferran/Spain
September 2010

Dear Troels,

It has been a while since I finished my PMS loudspeakers and I was waiting to finish my also DIY listening room to send you the photos of the ensemble. As a young and poor engineering student, I decided to go DIY for the whole process which started 3 years ago. At that time, I dismantled the table tennis room at home and converted in a dedicated 2-channel listening room with also a projector for film watching.

The PMS loudspeakers where the starting point. Having already built a loudspeaker kit (Seas' Embla) I decided to go for a floorstander, and I had the time and space to build their difficult cabinets. As seen on the photos, each enclosure has 7 braces, and everything is built from 19mm MDF. Internal damping is made from rockwool and polyurethane foam, bituminen pads and cabling is braided CAT6 with the number of wires proportional to power requirements between drivers. External finishing is fabric upholstered, with black HDF feet and a top cover made of phenolic resin custom cut to the loudspeaker' section profile. Crossovers are fitted in separate boxes behind the cabinets.

For the room building, I've studied acoustics and mechanical vibrations, and it has been designed for Hi End listening. RT60 is very well controlled to 0,35s in all the frequency ranges through absorption and diffusion, and all first and second reflections are controlled and adjusted by ear and by measurements. Aesthetically, I wanted the room to be black, to improve film projection contrast and to prevent reflected light from reaching the screen. I also wanted to obtain and "infinte" perception of music soudstage, at dimmlight, which is really palpable. I could write a hundreds of lines of the whole process, regarding room acoustics design, acoustical treatment construction, loudspeaker positioning and electrical installation but let's concentrate on the final result.

UOOO, is the first word a friend of mine said, with the first second of music played [he owns a 40k€ system]. The PMS are really on the HI End side of this hobby, and each day I enjoy them more. I completely agree with your thoughts regarding the overall character of the speaker, it's is dynamic and very natural sounding due to the lightweight paper cones, with a clean and fast bass response. I noticed that the bass improved significantly as I lifted the loudspeakers from the floor, and I recommend to the other builders to try it out. I finally left 11cm. 

The integration between drivers is magnificent, and I feel that the tweeter is in a higher league than its companions, as the treble is extremely transparent and detailed. As usual with this drivers, distortion starts to increase when demanding lots of energy from musical events but it's not a common situation in my musical tastes. Nevertheless the main and the strongest point of this louspeakers is their capability for soundstaging. In any system I've heard, there isn't a sense of depth as in my listening room. It's true that the speakers are far away from the front wall, and that acoustical treatments help a lot, but none of my friends owning 6 figures systems (+100k€) can't compare as per sense of scale and depth of the soundstage. Now I'm addressing the acoustics of the listening room of one of this friends (150k€), whose system is not really enjoyable due to acoustical problems.

It has been a long and time consuming process but the experience gained and the final result is totally worthwhile. A clear conclusion I extract from this experience is that room acoustics play a major role in this hobby and that it's always rewarding to look for better sound through experimentation.

I'll like to thank you for the design of this loudspeaker and for the immeasurable task you are doing to the DIY community . I want also to thank to my parents for their also immeasurable patience and to Maria. Please find attached a summary of the process in photos.
Best regards,

Off this topic:
1- Nice Web update :)
2- My Next station: DQTWT ;)
3- Recommendations for a 'hardcore' classical music loudspeaker (prelude, jensen, DQTWT...)
4- Very nice photos in all your projects, you take great care of this aspect!
5- PMS photos on next email.

Dear Farran,
Thanks for you thorough report back on the PMS project. I can only dream of how the PMS sound in your room. I'm sure a lot of speakers will benefit from proper room treatment, but only few have the possibility of a dedicated room for hifi. How the DTQWTs will sound in your room makes my dream even wilder!
Hardcore classical? DTQWT-mkII - and it can play hardcore heavy metal too!
Best regards, Troels