[James Edward]

I have the M3 Turbo S... Therefore, in the true spirit of our hobby- never leaving well enough alone, I will also be trying brass screws and listen for what changes may occur.
I won’t be removing the grille cloth, making the conversion that much easier. I’m also going to try and find some rectangular brass washers of some sort, to more evenly spread out the screw torque across the driver basket rim. Something like these:
https://www.nationalengfasteners.com/products/category/193-rectangular-washers
It seems a lot of expensive speakers make heroic efforts to really fasten the driver to the baffle, so maybe there is something to it.
In closing, I will say this: my wanting to try this should in no way be construed as disappointment in the M3. Quite the contrary, it sounds phenomenal not only for the money, but also in absolute terms. All these tweaks cost money and time in manufacturing and development; if Clayton were to spend more time tweaking, I suspect we’d no longer be looking at a $3,000.00 out performer. I love the sound of these things.

[ric]

Hi Tim, I can send a photo, but I did not do it for looks so I can tell you that it is not pretty. My M3's are flat black and so it clashes with the brass and white gasket (Herbies product). If I were doing it for looks (which matters less on the back of the frame) probably best to pre paint the screws and isolation gasket.

[ric]

And James, I would recommend removing the grill cloth as I am noticing cymbal strikes and dynamics that I had not before. In fact I was thinking that it would be great if Spatial had an option so that they could be removable, as doing so does make a difference.
If you do remove the cloth, it is not attached to the speaker and I suppose it may be possible to make or find a (plastic?) circle and glue it to that and attach with simple velcro mini pieces, or something like that.
Again, the dynamics and soundstaging to my ears are about 30-40% improved. I too love the sound of these speakers and am shocked how much improvement I am hearing. Of course YMMV.

[ric]

As per request here are a few photos:

[Steven Stone]

I wonder if merely tightening all the screws, which can and will loosen with time due to wood shrinkage and shipping vibrations could be most of the difference you are hearing...I always check and tighten all screws holding drivers on new speakers after a month...

[rollo]

I wonder if merely tightening all the screws, which can and will loosen with time due to wood shrinkage and shipping vibrations could be most of the difference you are hearing...I always check and tighten all screws holding drivers on new speakers after a month...

  Steven nice seeing you post. Good tip however not all drivers desire a vise grip. Some are to tightened to a certain resonance point.  Brass also has a different resonance factor than steel. Over time will not magnetize either. Cost more as well. Maybe it has to be measured. 





charles

[ric]

C'mon, somebody out there please try this to confirm or deny my claims of a 30-40% increase in Soundstage and dynamics. Even my diy hallographs are set differently to accommodate the difference in Soundstage. Good luck!

[Rocket_Ronny]

I will deny your 30-40% number. That is a huge increase. I would think more like 5-10% would be more in line. That's if we are still talking about the brass screw tweek.

Now if you truly want a 30-40% increase in imaging get your speakers out at least 6' off the wall. Just some friendly audio phoolary advice. Cheers

Rocket Ronny

[James Edward]

Ric, my M3’s are right in the middle of the living room, so removing the grilles is just not domestically feasible.
However, I will be doing the brass screw thing as soon as I get the supplies. As an aside, due to the open baffle design, you can see my dog thoroughly enjoying the approximately -6db null between the speakers. (Measured very unscientifically with a RadioShack SPL meter.

Maybe a moderator can turn my picture right-side up...

[ric]

Still trying to think of a way to have the grills removable. That way aesthetically pleasing when not in use. Hope your dog doesn't exercise by doing leg lifts!

[Spatial Audio]

Hi Guys,

Let me try to sort this out and comment from the manufacturer's perspective:

It is certainly possible that Ric heard something happen after making a change of any kind. But, the tweeks he is proposing are not recommended and interfere with the manufacturing design of the product. The M3 carries a 20 year warranty against defects and workmanship issues, but these tweeks void the warranty.

Lets take the two tweeks separately:

1) Brass screws - The important thing to consider is the baffle material being used - a high grade MDF in the case of the M3. As a material for speakers, MDF is the only good, reasonably priced, machinable material available, thus everyone uses it in the under $10K price category and some very expensive speaker (over $100K) such as the Sonus Faber Aida use MDF. The material, however, does not hold screw fasteners very well, so very coarse thread screws must be used. We do use drywall screws for this reason. Cost has nothing to do with it. Brass screws are not available in coarse thread to my knowledge, so the options are virtually none. There is a good screw known as a Tek screw, but they are not produced in the 1 inch length required in this application and don't appear to have any real benefit over drywall screws. The problem with replacing a screw to a finer thread type is that it can destroy the original thread pattern. The CNC router drills a precise diameter pilot hole in the MDF, so that when the drywall screw is driven in, it forms the thread pattern. If you trash the pattern, you will likely end up with a stripped hole situation. Therefore, it is bad advice to suggest M3 owners make this change and potentially ruin their baffles. As to whether brass screws sound better, I would leave that to the tweekers. But to suggest 30-40% improvement is ridiculous and should be challenged. The compliant washer Ric added would appear to be redundant since the woofer mounting face already has a stiff foam gasket that damps vibration. The entire woofer frame is steel, so what would a steel screw change even if it became magnetized? None of this makes any sense to me and indicates a lack of basic knowledge about mechanics.

2) Grille cloth removal - Ric's hearing must be world class, since the cloth is almost perfectly transparent acoustically . The cloth only attenuates the compression driver's output by 0.60dB as shown below. More importantly, the attenuation is exactly the same across the range, so the result would be that the range from 1kHz to 20kHz is now 0.6dB louder. 30-40% improvement in sound?




I have always encouraged experimentation because it is a great way to learn and fun to do. But, we need keep in mind the ramifications that can result from telling others to alter their products when based on opinion only. I would suggest asking me about any ideas for improving our products before tearing into them - we are always looking for ways to improve. I have heard of most of these tweeks before, so I may be able to save you a lot of headaches.

Best wishes for 2019,

Clayton Shaw
www.spatialaudio.us

[ric]

Thank you Clayton for responding. Let me note also that I stand by what I am hearing. Yes, 30-40% is high, but I would temper that affect with another possibility which is room loading. It is possible that a small increase sounds huge IF for whatever reason, in my smallish room, the room sounds full and saturated, due to a tweak, to the point that my Hallowgraphs no longer function in the same way they did before the tweak, and for that explanation I am at a loss.
     As I said, I had the grill cloths removed for one day before trying the screw tweak, and curiosity got the better of me, and I should have waited, although myself and others do hear differences (i.e. Dunlavys) when grill cloths are removed. I think I said there was a slight improvement without the grill cloths, (not 30-40%) and we also know that measurements as well are not always an accurate way of describing what one hears.
    This is why I was suggesting that others try these tweaks, because if someone else hears ANY difference, something is going on. But this something needs to be verified, in this case by consensus.
    For the record, the brass screws I used are slightly larger than the sheetrock screws so they do work, but changing back to the sheetrock screws could be a problem as those holes are slightly larger now, and would need a larger diameter screw IF the MDF is overused.
As far as the washer material, it is a Herbie's product, made for this type of application and I am assuming that it is different acoustically than the foam you are using. Now whether this has any influence on what I am hearing I have no clue without removing them and using my ears.
    Tweaks are supposed to be a fun and interesting and sometimes rewarding way of hearing changes. Now, if these tweaks void a warranty or poise a danger to the integrity of the material then of course they shouldn't be done. Now unfortunately, I have no consensus in either direction, but based on what I am hearing, I am suggesting that you, Clayton, TRY some brass screws. After all, if this improves your product that's a good thing.

[glynnw]

Yes, tweaks are fun, but business is business and you have voided the remainder of the warranty on your speakers.  I suggest you send Clayton the serial numbers so he can record that the warranty is no longer good, in case someone else has a problem with this pair 15 years from now.  I am not trying to be snarky - just want to protect future owners.  I have done lots of similar stuff, but only on units with no warranty.

[TimS]

I wonder if merely tightening all the screws, which can and will loosen with time due to wood shrinkage and shipping vibrations could be most of the difference you are hearing...I always check and tighten all screws holding drivers on new speakers after a month...

Clayton, do you recommend doing as Steven suggests above about checking/tightening the screws after a few weeks?
Thanks

[Spatial Audio]

Yes, just don't over-tighten them since its MDF.

Clayton

[James Edward]

glynnw, I opened the cover on my amp once, I confess.

[glynnw]

James Edward - How do you sleep at night knowing what you did?

[ric]

In response to Glynn and voiding the warranty. I would suggest that ANY problem with speaker attachment would void that warranty, but to be fair, if the tweeter blows and it is not the fault of poor attachment than I would hope Clayton would honor that. But I'm happy to pay for parts, as they do wear out over time.
Many apologies for opening a can of worms. Yes, I should have checked with Spatial first about the screw attachment and I DO realize how fragile MDF can be in terms of screw attachment. It would be a major PITA to repair a crack or separation that would not allow a screw or screws to hold.
It may be best to delete this whole topic, as I would not want someone who has read part of it only, run the risk of doing what I did, unsuccessfully, so Clayton, perhaps deleting this whole mess? thanks!