[Bwanagreg]

I've been on a minor tear recently, trying out the Pwave amp, the Dakiom devices, I ordered diffraction panels for the rear of my room (not installed yet), and I've been trying out a few tweaks on my TS-1's. Here is the list so far, in the order I added them:

1. Pwave amp
2. Diakom R103 feedback stabilizers
3. Thin Sorbothane squares under the speakers.
4. Cotton stuffed behind the whizzer (the famous $.02 tweak).
5. Grounding the driver basket to the + terminal.

This last one (grounding) has got me buffudled and verklempt. I found the idea on Audio Asylum's HUG and tried it last night. I took a short length of magnet wire, attached alligator clips to each end, and then attached one end to the driver basket, the other to the + lead at the terminal strip. The theory/rationalization behind this tweak, which is claimed to work for many Fostex drivers, is that capacitance is built up between the basket frame and the voice coil circuit. The wire grounds the two together. I think Moray James is credited with the original idea.

Until I did this last ground tweak, I was enjoying the sound (as I've been saying in my comments on the Pwave), and each incremental tweak beyond the Pwave perhaps improved things a bit, but not radically. Then I did the grounding tweak. As I listened last night, I was struck by the fact that this was the best this system has sounded, and by a noticeable amount. I am particularly irritated by glare, and it reached new low levels last night. The whole palpable presence thing that single-drivers are great at ratched up a notch or two also.

Was it the grounding tweak? That was the only new thing yesterday. Was the Pwave or the Dakiom breaking in? Maybe, but that suddenly? Was it the Scotch - just kidding. Do I have to go back and remove every tweak to find out?

Anyway, that's what I have tried so far for what it's worth.  Has anyone tried the grounding tweak? It seems to have had the single most impact so far.


System (2 Channel configuration):
Power conditioners: Two OneAC, One Powerwedge
RAM CD Player
Dakiom R103
Old mid-line Audioquest interconnects (line level and digital)
NAD 752 (DAC, surround processor and preamp sections only)
Dakiom R103
Old MIT Interconnects (suppose I need new interconnects? )
Powerwave Amp
Mapleshade Speaker Cables
Cyrotweaks Speaker Bybees
Omega TS-1s
Rava Sub
LEDE room treatment treatments (in progress)

[moray james]

Hi Greg: thanks for the credit but I think that the idea is very old, the only credit I can take is for thinking about it too. Nothing new under the sun as the saying goes. You need to experiment with both polarities. Sounds like you have the best connection for your set up but it is best to listen to both the positive and negative connections. Of the two one way will clearly sound right and the other not as good.  
   This wil probably sound silly but you should also listen to both possible combinations of amplifier phase. Switch your speaker cables around with respect to absolute phase. Sometimes you can get a real surprise when you do this. This is easy and painless so give it a try too.
   Morse has done lots of great work in driver tweaking do a search on AA Tweaks. I think that installing machine screw inserts and machine screws to mount your drivers will work small wonders.  Further you can install 3/4 inch #10 flat head wood screws into the bottom of your cabinet (I use a tripod mount) flust to the bottom surface (these screws point into the cabinet, they do not stick out) and positioned so the screws fit inside the dimensions of your stands top plate. Then I use Noel Nolan's new ceramic feet to interface between the speaker and the stand directly under the inset screws. The screws act as a kind of stiffining energy sink for the cabinet and shunt away vibration into the stand via the foot. The Steel nut and washer feet that I designed and posted here also work really well to do this job. I lock the three wood screws into place with a little slow set epoxy when I screw them in place. These are ultra simple mods which will help a lot and cost almost nothing. Le me know how things work out. Best regards Moray James.

[Bwanagreg]

Moray,

Thanks for the additional ideas.

Am I roughly right in my description of the reason why the grounding tweak works - some capacitive effect between the driver basket and the magnet structure? If that is true, I suppose this would be a bigger problem with the larger full-range drivers, and that small tweeters would be the least affected? The tweak really is a remarkable improvement given it's simplicity.

I'd like to see if anyone else with TS-1's can replicate my observations with this tweak.

[moray james]

Greg: I cannot say with authority exactly why this tweak works. I am guessing that it is more of an active "charge bias" effect. I have installed a swithch (three position) which allows me to select connection with either the positive or negative speaker terminal and also offers the option of switching th mod completely off. I have had sucess with both tweeters and compression drivers using this idea.
   Triodeuser (Ken) over at HE AA has had very good results with this mod on his FE206E Fostex drivers mounted in a front horn. The difference in some drivers is such that without it the driver sounds as if it is sick.
   I hope that you can find others to give this modification a trial. My experience has been that when you suggest ultra simple mods which have significant impact and which can be easily reversed hardly anybody wants to experiment. That said if you tell people to paint thier brand new Fostex or Lowther drivers with some esoteric goop which sells for more than a barrel of crude oil and comes in a 10cc vial which is also a perminent treatment and takes 3 months to cure they are on line with thier credit cards in minutes. I just don't get it. I am not against any exotic modifications but I think that most folks could go a long way toward improved sound without ever loosing any resale value of thier driver with simple mods. As I said before Morse has done a lot of work to establish easy to do mods which all make sense and work well. Following that lead will take a poormans driver beyond many stock in the box esoteric drivers. I always though that this was all about raising the bar in terms of performance vs cost. Have fun and enjoy. PS take a look at the back loaded horns designed by Bill Woods of Yorkville Sound (RCA-fan) in his photo gallery over at the HE AA forum. They will take FE208 sigma's or Lowthers. Very cool! Regards Moray James.