Hi Kirk,
I used to own the Meadowlark Osprey. Funny how I never knew about the driver damping material, however, I never had to replace a driver while I owned them, nor did I ever have a thought of needing to check for their driver screw torque. Too bad that Meadowlark's no longer around. They sure made some great speakers. |
Tvad,
Sounds like a good idea. I don't have a Wheeler Fat Wrench, but I do have an older Black & Decker battery-powered driver that has similar adjustments. I recall that the video suggested starting at 8 ft.-lbs. torque. I think I'll do the same initially on the stock screws. I just came back from Lowe's and bought 3-packs of solid brass screws of the exact size of my speaker driver's screws. Each pack had six screws at $.98/pk. |
I agree that the equal torqueing of the screws probably is as important as the composition of the screw. |
Apparently this Fat Wrench is offered in a couple of versions. Here is a site where the model shows 5-60 lbs. I don't think the differenc ebetween 8 and 10 lbs. would be that dramatic. Chances are if you manually tightened the screws down it would be more than even the 10 lbs. so you should be fine.
http://www.amazon.com/Wheeler-553-556-Wrench-Variable-Torque/dp/rebates/B000Q2AYF8
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I think you'll be fine. I just did a torque test on one of the original screws on one of the midwoofers and it was about 10 lbs. Actually, I pre-tested all four screws on a mid-woofer driver and all four were slightly different. Hmmmm... interesting. Also, a correction: it is inch-lbs. not ft.-lbs. Even if you don't hear a dramatic difference, you can always use the Fat Wrench for your hunting and target rifles. Or if you don't hunt or shoot, it would make a great gift for a relative who does. (O: Let's have some fun. |
Well, I guess I'll be the first to be in line for flames from the other side. I initially equally torqued all my stock screws to the same 8in.-lbs. Soundstage appeared to be a little cleaner and a tad more focussed and centered. Nothing really revelatory. I then put the brass screws in one speaker only. I'll be danged if that speaker with the brass screws didn't suddenly sound a tad louder with a cleaner, crisper sound than the other side. Since I have small mini-monitors, I swapped the speakers and sure enough, the brass-screwed side sounded better. I listened for a while to make sure what I was hearing wasn't some subconscious desire for the sound to be better, then I put the brass screws in the other speaker. Sure enough, the other speaker matched the first with brass screws. I can say that this isn't a night and day difference, but the whole soundstage sounds a bit taller now and wider and deeper. Depth seems to be the most improved. The overall sound is a bit cleaner with better transient response. To my ears, a very slight haze or veil has been removed. I think I'll leave the brass screws in for a while. |
Sorry, I'm not going to over do it with the torqueing. I might try it at 10 lbs. soon, though, to do a quick comparison. |
I had an old Black & Decker already. |
Have you noticed an improvement with the felt around your tweeters? It makes one wonder why the manufacturer didn't do this if it does improve the speaker (as it is a cheap tweak). I guess the same question would apply to the manufacturer as to why they don't use brass screws on their speaker drivers, assuming they make a sound improvement. |
I wasn't aware of The Absolute Sound award as I don't subscribe to any reviewer mags any longer. Many years ago, I subscribed to them religiously. |
I just received an e-mail from the manufacturer of my speakers after I asked them if the screws on my speakers had to be a certain torque. His response was, " You want the screws to be firm, but not too tight to avoid stripping the screw holes." |
Well, the credit, although known by some for a while, must be given to the owner of Virtual Dynamics. I simply brought it up for discussion. |
Anyone else try the brass screw replacement and torque experimentation? I've been experimenting with different in.-lbs. and the results have been interesting. I've only tried 3-10 in.-lbs( I'm not so sure that my old Black & decker is accurate) but so far, regarding torque, too much thins out the soundstage and too little muddies it up. With my B&D driver, on my speakers, 5 in.-lbs seems to be just right( on both tweeters and mid-woofers). But I want to do some more listening and fine-tuning. I sometimes hate being an obsessive-compulsive personality. (O: |
Tom,
Can you share what Rick recommended as far as using magnets instead of fuses in your system? This is intriguing. |
My speakers are Reference 3a Dulcet. I e-mailed the main man, Tash, at Divergent Technologies and attached the VD video. He emailed me back telling me that the video was interesting and that it made sense to him. Tash asked me to run my personal tests with the brass screws and torque tests. I followed up telling him how the brass screws made a nice difference and explained to him how I came to fine-tuning the torque to achieve the best sound possible from the Dulcet. I suggested to him that he try his own tests in the factory and asked him for his results. So far, no answer from him. We'll see. I feel that this is a very good tweak and the laws of physics are in play here. I'm no physicist, but I'm thinking that the proper torque somehow is related to the screws matching the resonation of the cabinet with the speaker drivers. Perhaps someone can explain this phenomenon. It's obvious that the brass, being non-ferrous, doesn't negatively react with the driver magnets and brass has good drain-resonating characteristics. Help me here, tech guys. |
Tom, besides switching to brass screws for your drivers, have you experimented with the torque? I'm curious what the proper torque should be for those inner screws for the tweeter, or maybe it depends on the type and brand of tweeter. I recall finding a thread on AA how the Merlin speaker driver's screws are properly torqued at the factory and some owners check for torque maybe twice a year. I remember that the inner screws on the tweeter are torqued higher than the outer screws. |
Tom,
I understand the tuning by ear. Although I was experimenting with the torque using a screwdriver with a torque setting, I could hear the difference with each incremental setting. All this tweaking with the brass screws and proper torqueing not only puts the soundstage into perspective, but the best tone, timbre, and dynamics are also achieved when the setting is "just right".
Currently, I am using some heavy metal stands filled with playground sand. My floor is a concrete slab that is carpeted with a 1/2" foam padding under the carpet. The stands have basic cheap steel spikes that came with the stands. I am considering buying some Audiopoints, but I have read that the Audiopoints are more effective on a wood floor. I am de-coupling my mini-monitors from the stands with squishy isonode feet. |
Sorry, Grant. I got carried away with other tweaks in mind. Sometimes my brain gets ahead of me. (O: |
Thanks, Grant. I did start this thread, but I'm looking forward to some more positive posts( or negative, if that be the case) from others. Sometimes I feel like I'm talking to myself. Hey, wait a minute! I DO talk to myself! Anyway, I'd sure like to hear your impressions when your Fat Wrench comes in. |
Albert,
Maybe you can check with your Dali dealer or ask a factory technician about the torque. They might pre-torque these to factory specs and then, as you mentioned, they might put some lok-tite on the screws to keep them from loosening with time. It made me cringe to see that you couldn't tighten them with " all my strength..." You don't want to break off a screw or strip the wood out. |
I searched all my local hardware stores as well as the more popular "nuts and bolts" boutiques and let me tell you folks, brass screws, particularly brass machine screws in small metric sizes( ones needed for my tweeters) were very difficult to find. Most don't stock specilty brass screws because brass screws were almost all replaced by stainless steel screws a while back for most contractors. Although stainless steel is non-magnetic and holds up better to the environmental forces), it still causes "Hysteresis"( did I spell that right?) when in close proximity to magnets. Brass is still the screw of choice for things audio related. Most of the sales people told me that brass screws these days is mainly used for decorative purposes. After a lengthy google search I found a good supplier where I could order directly from their website, Mcmaster-Carr. here is a link for those interested in pursueing special-sized all brass screws for their speaker drivers:
http://www.mcmaster.com/
Just type in "brass screws" in the search window on the left and it will take you to a list to choose from. Prices are very reasonable. I got a box of 50( minimum order. I only needed 16 total, so I have plenty extra) of a metric machine brass screw of M4.7 x 6mm for $9.00. I just replaced the steel screws on the inside of my speaker tweeters and the sound is much more natural and open. I haven't yet experimented with torque, but just changing to brass made a nice improvement. I also found a very nice calibrated Proto torque screwdriver, made by Stanley, (retails for $200.00) for $40.00 on Ebay. |
Grant,
It depends if your screws are US or metric. You'll need to take one of each type of screw you intend to replace to a hardware store or Home Depot,Lowe's and measure for thread type, length, pitch,etc. so that you exchange out for the same in brass. I actually had to buy two types, one wood for the external tweeters and woofers and metric machine type for the tweeter internal screws. I can send you some of mine, but if they're not the same size, you could strip out or damage your speakers. You could always contact the Silverline tech and ask them what the screw measurements are for your speakers. That would save you the time of taking them out and to a store to measure them. If the size is the same as mine, I'll send you some. We'll e-mail privately at that point. I had a very positive transaction with McMaster-Carr( my first). I got the screws from two different warehouses within 3 days from ordering. If you look at the McMaster site, you'll see that they have a variety of heads to choose from. My external driver screws are panheads( factory screws are allen type, but I chose philips. Slot head might also be available. My internal tweeter screw heads are flat heads, philips, that are for presunk machine thread holes so that the heads are flat with the tweeter plates. |
How are those Sistrum platforms working out for your speakers? |
Ouch! They must not have been packed very well. Are you still contemplating trying out a pair in the future? I saw a used pair for sale recently( maybe that's the same guy that sold to you) as it was marked for sale in the heading but the ad remained there for a while. |
Hey, Tom! Put me on your list for that Brass T-shirt. I play a brass instrument( trumpet) as well. |
