New P20 ..... more details please?


@ John_H That looks gorgeous! Are those the lovely Von Schweikert VR 55 in the background?.. I own the VR5 Anniversary Mk 2.5 (last ones made), and will be keeping them for a LOONG TIME.

I am planning on a P20 sometime later this year or early next (as soon as funds allow). I cant see how using a P20 to run an entire system will not improve the entire system. Please let us know the improvements to your system with the P20s in :-):grin:


Elk - So I decided to add a pair of REL subs to the SF Guareni Evolution main speakers. I plugged them into the P20 group (high current); that group was free and I wanted to make sure there were no power issues to the subs. Each sub has a 350W amplifier. The REL subs are magnificent and add bass extension to the SF main speakers. Good subs that are well placed are not heard from, just a bass extension of the main speakers as a sound stage. Now the sound stage has so much more presence.


Great choice – the REL’s. What’s up with the tube traps being elevated? Just curious…


Scotte1 - So after multiple emails with John Hunter, I decided to remove the lower 3ft section of each corner 16in ASC isothermal bass trap. This would give the sub a footprint; as you can see, won’t fit in the corner with 9.5ft tall (6in stand) bass trap. I put the (2) 3ft sections together and placed them on the glass rack top. There are (3) high pressure areas for LF - attack wall corners and attack wall center, all at the ceiling is the highest pressure. I have not added the stacked 6ft bass trap yet. I’ve bought the hardware needed to measure the room using REW (Room Eq Wizard) software. I bought a J-Tech HDMI to TOSLINK convertor w/ 12ft TOSLINK cable and a USB mic with stand. I will now remove all the acoustic treatments, then measure the room and add back the bass traps where needed. So, the “answer the mail” answer is room for the REL subs and the highest low freq pressure is felt at the ceiling. Below is the initial room with no subs. I also performed the SUMIKO “master” speaker placement procedure which moved the main speakers out toward each wall. The room is small so LF content is difficult to manage. This increased the size of the sound stage from 6.5ft to 8ft. I then moved the 13in bass traps further back. All of this acoustic treatments may change depending on the room acoustic measurement results. This is a work in progress.



You might want to experiment with moving those REL subs out of the corners. They are so good that, in my experience, corner loading is not universally the best placement.

Since you are going to employ REW, you should be able to see what works best with some placement and measurement experimenting. I suspect that you also have room nodes to deal with in the corners near the floor. But, you are taking a pretty sophisticated approach, so I am sure you will end up optimizing your set up as best as you can. Have fun, and thanks for the reply.



FWIW, I have a single sub set up in my big rig at home (huge, “vintage” SVS ultra plus/2) and my office system (REL T/5i). In both instance, after experimenting with different placements, I have settled on placing the subs slightly out from the right wall about 1/3 in to the room from the front wall. With the REL, in particular, I just could not tame it with corner loading. Now it just disappears. I don’t have any corner traps (yet) so that might partly explain where I ended up.



Scotte1 - This room is a lot more complex than you assumed, based on pics you have seen. The fact that this room is small is lost on the rear geometry; causing the very low end to be reduced substantially (20Hz - 30Hz; 10dB). If it was sealed room, the opposite would happen. I got this room measurement SW & HW just to see how bad the room really is and it is bad enough. In addition, I have moved out the subs quite a bit and they sound their maximum in the corners, disappear, and keep up quite well with the SF main speakers. They are located about 6in from each wall at 45 degrees into the room. These SF mains and REL subs create a sound stage and I never listen to speakers, including the subs… just a sound stage, they disappear, sounding like a bass extension of the SF main speakers. What I like about the REL subs is their ability to disappear and the sound stage now has presence in the first few octaves. I am in the process of listening to my favorites over. Queen’s greatest hits sound amazing with the low end extended. They loved their bass and now I feel the music. In addition you have to watch out, these REL subs can now be heard on the other side of the house outside. Make sure all your wall art is buffered, they are powerful; however, not in a bass bump sense, just low end clear & beautiful presence. I just got them last week so there will be a lot of movement, crossover & gain measuring and sound testing. This will be a lot of fun and will take me months of fun. I will keep you posted.


Scotte1 - having a pair of REL subs may have something to do with not really needing to move them toward the center of the room. The pair together is really powerful and I don’t need to have them cranked up. However, I will play with the placement and I appreciate your insights.



Understood; thanks for the response. Glad to hear you have been so successful in making the subs disappear. The REL’s really are impressive, aren’t they? Have fun.