Mach One 4024, 4024A, 4029 Information and Upgrades!
- Thread starter Raddek
- Start date
juniorJBL
SUB 1500 :)
Nope will not hurt it.
Use it at work all the time as well as stuck to my Ewave horns.:thmbsp:
monkeyking
Active Member
Nice find. Thanks for posting that.
I like the bit about "If you like to listen to music at levels similar to a concert hall..."
They really do come alive at the higher levels.
I like the bit about "If you like to listen to music at levels similar to a concert hall..."
They really do come alive at the higher levels.
HomeBody
Passion not Critisism
Did you remove the L-Pad from the cabinet? How could you see what to do if you didn't....?
I've thought about the insulation, myself. Removing some or adding some to test the effect on Q factor.
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dc270
Now Off the Reservation
Did you remove the L-Pad from the cabinet? How could you see what to do if you didn't....?
I wrapped mine w/old, worn out long-handles I had in the bottom of my chest of drawers.
I've thought about the insulation, myself. Removing some or adding some to test the effect on Q factor.
I just wrapped masking tape over the back of the LPads so the vent holes were covered. The main object was to deaden the rattling plastic potential! They did not need to be removed.
Padding the mid horns did help tone down the sympathetic vibrations that transfered into the horn. It does sound cleaner. I learned this trick on a pair of Altec 811-B horns- it woked very well indeed! The lower mid range on the woofer also improved as well. Try thunping those frame spokes and you will hear a distinctive ring- even through the cone. Padding those woofer frames made nothing but good sense as well!
Resonance has real effects on and in speakers. It is not limited to just the cabinets but everything else in it! It all adds up IF you care to look and cure what you can.
Let me & others know your results should you care to.
DC
HomeBody
Passion not Critisism
Well, that gave me the idea last nite to perhaps use some duct tape on the driver spokes. I wanted to remove the L-Pad section...so I took the screws out and discovered that it was way too tight. My fingers were almost white-knuckled and I didn't feel like risking any breakage so I put the brakes on.
I'm gonna look around for some lumber I have lying around...cut a brace to size and test. I can't say I've heard any ringing from the woofer.
What music are you listening to that gives you a ring effect...and at what volume level per say....
Two things peaked my curiosity...
I noticed the absence of a gasket on the woofer...So I believe the vinyl on the speaker faceplate serves as a gasket.
Thoughts?
I pondered the idea of a gasket for the horn driver and the bell...
Thoughts?
I'm gonna look around for some lumber I have lying around...cut a brace to size and test. I can't say I've heard any ringing from the woofer.
What music are you listening to that gives you a ring effect...and at what volume level per say....
Two things peaked my curiosity...
I noticed the absence of a gasket on the woofer...So I believe the vinyl on the speaker faceplate serves as a gasket.
Thoughts?
I pondered the idea of a gasket for the horn driver and the bell...
Thoughts?
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HomeBody
Passion not Critisism
I install dowel rods I had around the house (1 inch boys) for the side-to-side bracing.
I didn't get to fully audition the end result. But for my ear, the improvement was there-
Slight, but there.
I'm not getting the bell ringing from the woofer, however.
I believe I'd have to pump up the volume for that to happen...
By that time, the room would be too full of sound for me to pick it up.
I'm not saying it couldn't hurt. Isolation, is for the most part, a good thing.
I didn't get my head into the cabinet- is the L-Pad/Horn plate screwed to the speaker front or is it glued (Christ's sake) ???
I didn't get to fully audition the end result. But for my ear, the improvement was there-
Slight, but there.
I'm not getting the bell ringing from the woofer, however.
I believe I'd have to pump up the volume for that to happen...
By that time, the room would be too full of sound for me to pick it up.
I'm not saying it couldn't hurt. Isolation, is for the most part, a good thing.
I didn't get my head into the cabinet- is the L-Pad/Horn plate screwed to the speaker front or is it glued (Christ's sake) ???
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dc270
Now Off the Reservation
Sounds like you are on to good things here! If you run test tones through the system that can help identify resonances. As for the woofer frame rining I think was was hearing the ring worst around 500~800hz. This was at a moderate volume mind you- but still was there. If it is in your test tone trials then it is in your music-you may not notice it due to some music complexity.
Keep your coments coming- I do not wich my observation to be unique- unless they actually are!
DC
HomeBody
Passion not Critisism
I'll pick up another large dowel rod on my trip to town next week...for the front-to-back bracing.
On the lighter side-
If I have a belling effect coming off of the driver spokes....
Maybe that's making the Timpani sound more authentic
I'm seeing a whole team of psychiatrists....
On the lighter side-
If I have a belling effect coming off of the driver spokes....
Maybe that's making the Timpani sound more authentic
I'm seeing a whole team of psychiatrists....
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audiozaz
rtfm!? - tl;dr
Each time I've worked on bracing, stiffening, padding, damping any of the many and various structures in a loudspeaker driver and/or enclosure, results were immediate and apparent.
That type of mod is usually very cheap, simple enough and not too time consuming. I feel this should be done before worrying about cables or other "last ditch effort at improvement" type of mods.
az
That type of mod is usually very cheap, simple enough and not too time consuming. I feel this should be done before worrying about cables or other "last ditch effort at improvement" type of mods.
az
dc270
Now Off the Reservation
I concur completely. I personally think those extra resonances truly subtract from a speakers best potential. You are correct as well when you stated that addressing those resonances is simple and not too time consuming- especially for the return one can get!
First time I looked into a B&W cabinet and noticed all the estra bracing it woke me up to why it probably sounded so good. When I looked inside otheer premium sounding speakers they usually had that in common. When I applied that logic it worked exceptioanly well and should for otyhers!
It is like trying to have a private conversation when there is a jack hammer working 10 feet away. The best part is you can easily turn that jack hammer down with a bit of effort, materials and time.. I keep plenty of 2"x2" around and save all my driver cutouts just for bracing purposes.
Speakers, in general, can be the easiest bang for the buck to improve. The best part is you can hear it to believe it too! I don't know about others, but I like to see obvious results for efforts.
DC
audiozaz
rtfm!? - tl;dr
Of course what I said does not apply so much to big buck$ speakers that are likely to have this stuff largely taken care of out of the factory. But those of us on the prowl for vintage "mid-fi" speakers can put this stuff to good use and go great lenghts towards much better sound.
Some of those speakers will generaly have good components and overall good build quality, but being built to a price-point, might skip on the afforementionned details. That's where we come in!
az
Some of those speakers will generaly have good components and overall good build quality, but being built to a price-point, might skip on the afforementionned details. That's where we come in!
az
Arkay
Lunatic Member
I've done similar things to a variety of vintage speakers, almost always to good effect. A few of the "New England" ("East Coast") speakers seem to rely on cabinet resonance to boost their bass sound a bit; really dampening and bracing ARs changes their sound considerably, and they start to sound a bit "dead" if you overdo things, but up to a point, they'll improve.
Don't forget the corners of the boxes, either. Just as with bass waves in a larger room, they are important points to absorb lower frequencies, to cut the extent to which the box becomes just a big resonator (think of a guitar body). I glue/stick some good sound-absorbent foam into the corners first, and sometimes all over the inside of the box, before replacing the fiber-fill stuff.
Adding weight/mass to a speaker to "anchor" it better, also helps. You can put a wrapped paving stone or a sandbag on top of a speaker -the difference is usually quite audible.
Don't forget the corners of the boxes, either. Just as with bass waves in a larger room, they are important points to absorb lower frequencies, to cut the extent to which the box becomes just a big resonator (think of a guitar body). I glue/stick some good sound-absorbent foam into the corners first, and sometimes all over the inside of the box, before replacing the fiber-fill stuff.
Adding weight/mass to a speaker to "anchor" it better, also helps. You can put a wrapped paving stone or a sandbag on top of a speaker -the difference is usually quite audible.
Maxamillion
Super Member
HomeBody
Passion not Critisism
Yeh, it dawned on me that I was changing the color of the lower tones. Then that brought to mind my understanding on speaker building. Hi-Fi builders depend on the over-tone of their cabinet design as part of their final sound output.
As I understand it, Speakers are a musical instrument unto themselves. And the cabinet's characteristics are unique, just as the type of wood or metal that are used to construct other musical instruments.
Back on topic-The change was apparent.
I found a 1x2 in the shed yesterday. So I was able to cut and brace up the front/back panels. Then auditioned the speakers thru a Pioneer SX-3800.
Material included-
Steely Dan: Two Against Nature
Swan Lake: Neapolitan Dance
Glen Campbell: Live
Led Zepplin: Presence
I noticed the timpanis dropped (lost of resonance) on the Swan Lake track...which brought me back to mind on the cabinet's coloring as part of the system. But with the other three artists mentioned above, the bracing effects were most welcome. I think I'll leave the braces in place.
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westend
Audiopile
Mortite works well to reduce vibration on the woofer frames. I've also used felt to cover the back of the magnet. I think a lot of this has to do with standing waves inside the cabinet. The back audio wave excites everything, woofer frame, cabinet panels, separate mid enclosures, tweeter magnets, etc.. Anything you can do to eliminate these resonances will improve the sound, IMO. Fiberglass does a good job for most enclosures, probably eliminating most of these standing waves. Of course, anything to reduce them at the source is going to be better. Good job on the Mach's!