Results lowering the resonate frequency by cutting welds.
Пікірлер: 19
@swingarmer2 ай бұрын
Then you can replace the removed material with a material that will damp them further. Could be as simple as silicon caulking! Thanks for this!
@MrNeverlift2 ай бұрын
Yes that works. I did try fill ngin the gaps I cut with fiberglass reinforced Bondo. (car body stuff). In fact when striking with the screwdriver it was completely dead. It went THUD! Out of the attempts in damping the hone, this absolutely worked. However, they did not sound as good. with music. Of course there is nobody hitting the horns when I am listening to music. As I point out in the video, the problem is not that they ring like a bell when I hit them. The problem is that they ring at the wrong note and that demonstrates they are out of tune.. Deadlining the horn did not give me good results . Tuning them did. These were meant to resonate at 811 hz which is below the 1,200 hz crossover. Most of the 811 horns I come across resonate upwards of 2,000 hz which is in the range where they are meant to play music. That is why they would have a sharp or hot spot when listening to music. The hot spot is gone and the rest is still lively.
@josephfinn62442 жыл бұрын
Excellent Steve, as long as your ears tell you it sounds better - it's better!
@tybotti8 ай бұрын
I found that the lips of the horn produce most of the noise. I bought automotive door edge guard, and fit it onto the edge of the lips and the ringing stopped.
@MrNeverlift6 ай бұрын
Thanks for watching. Sorry somehow I missed you comment until now. When you say the ringing stopped do you mean when you listen to music? My video is not about getting rid of the ring when you strike them it is about changing the resonate frequency which you may have done if the trim is causing some sort of detraction at the edge. In essence changing the shape of the horn.
@phrayzar6 ай бұрын
Once they are bolted to the driver with a cork gasket, the ringing is 90% gone. I have some sitting on top of my speakers with some auto deadening sheet un the underside and no ringing at all.
@MrNeverlift6 ай бұрын
Thanks for watching. In the video I clearly state "bolting them into the cabinet provides adequate damping". Also if you look close at the silver horns you can see the cork at the edge of the flange. I am only dinging / ringing the horns to demonstrate they ring at different motes. I have tried many, many different ways to add damping to the point where the horns did not ring at all and that is when I realized the problem I was trying to fix was the horns are out of tune.
@MrNeverlift6 ай бұрын
Sorry I missed you were talking between the driver and horn. Yes the cork is way better than the old cardboard gaskets.
@thanhphamAltec Жыл бұрын
horn altec lansing gold
@Danielvanderpoll11 ай бұрын
Could you give any advise on how to refinish and paint these cast alu horns? Im currently working on a restore project.
@MrNeverlift9 ай бұрын
Hello, Sorry I did not see your question sooner. Besides cutting the welds I had them sand blasted. Then I used Rust-oleum Universal Spray cans. They can spray at any angle, even upside down. I have used the Hammered finish straight on without any primer or surface prep. Came out great and the paint is easy to apply. Heals well and doesn't run or sag easily. Also I have primed and wet sanded. Made paint sticks with foam on the end and emery cloth wrapped around the foam to reach in to deep spots. Then i used Rust-oleum Universal Metallic. Got a real smooth finish as opposed to the Hammered. Also if you want a smooth finish I recommend the sand blaster uses fine sand (may need to be a second pass) as the blaster I go to usually is using pretty heavy sand.
@michaelboland7987 Жыл бұрын
Interesting. What type of saw did you use to make the cuts. They look very clean.
@MrNeverlift Жыл бұрын
I use a Saws-All with pretty fine tooth blade. I have made a little clamp on straight edge and I start with the saw blade in full contact with the flat surface of the vein and make a good score. Go slow. Once I get a good score I remove the guide plate and put a little attack angle on the blade (cutting against the edge some). Go slow. Pick the weld with the biggest buggers to determine how wide the gaps will be. You can cut through the actual welds but it is harder to make a good cut. If you want to cut through a weld bugger then it pays to file it flat first. After cutting, some filing to smooth things up. Then sand blast. You are likely to encounter some small air bubbles or imperfections. I use fiberglass reinforced bondo to fill any if needed. Then sand a little. I use Rustoleum All in One that keeps spraying at any angle, even upside down. An interesting note. I did try completely filling the gap with the bondo. The result was a completely dead horn. Way deader than any damping I had tried. All of my damping experiments were a failure. The hot spot no longer hurt my ears, but there was not much left exciting my ears either. So the choices where, real exciting sound with a hot spot. or real dull sound with a bump. Cutting the welds gives me real exciting sound without the hot spot. I used to sell Model 19's back in the late 70's. The "Harsh Horn" as we nick named it was already a problem. Some were good and some were bad. My best guess is that there was a lot of unpredicted variance in the welding process. Most notably the time lag between casting and welding. Also, cost and availability of foundry vendors / alloys was a problem. I have purchased 17 of these 811's in the past 3 years. Only 2 of them "ding" near what I believe to be what Altec intended. The rest of them are all over the place. I have also Cryo / Heat treated. The horns with the cuts held their shape and I think are the best so far. I had one done like this with the welds still in. It sounds fantastic. The only problem it the lips or the horn all warped like a ridged potato chip. That demonstrated to me the pent up tension in the castings. I discussed this stuff with someone I know who worked at a world famous trumpet manufacture. The response was pretty much, well duh, of course.
@michaelboland7987 Жыл бұрын
@@MrNeverlift Thank you so much for your thorough and thoughtful answer. I had wondered as well about either cutting these welds or possibly filling the gaps and then filing them down. I'm currently building a slightly modernized pair of Altec 620A cabinets with a removable upper front baffle to house a 416-8b and I am planning to use interchangeable horns and compression drivers up top. I currently have the JBL 2380A horn with the 2446H CD but can also get a nice pair of 811b's with 807-8A drivers and N801-8A dividing networks. I intend to build sleds for them either way for some damping and also to protect the upper layer of the cabs. Also, the intention of the removable front baffle is to have the option to switch over to 604s at some point down the road. Thanks again for your answer and your video. Much appreciated.
@MrNeverlift Жыл бұрын
@@michaelboland7987 I built Model 19 / 620 hybrids. 42.5”H x 19”D x 26”W. 416B, GPA 802G II with load caps removed and GPA crossover. I found that the acoustic panel from Amazon. typically 12’ x 12” x 1/2” high density (no foam) can be used to tune the cabinets. Doesn’t take much and is very effective. It cuts with a wood burner with hot knife accessory or just a sharp razor blade. You can experiment with placement. I would attach picture but don't think I can on youtube. Great Plains has a Face Book group. There are pictures there. They are pretty easy to spot. Black with Fender Grill cloths. You will also see a pair of model 19 with the same general look. I recently sold those.
@signalpath9597 Жыл бұрын
I can't seem to find the pics on there. Feel free to find me in the group. I'd love to see them. Thanks!
@MrNeverlift Жыл бұрын
@@signalpath9597 I sent some pictures to signalpath@gmail
@josuesantiago723 Жыл бұрын
Hi my friend what color green is the 811 horn
@MrNeverlift Жыл бұрын
The green horn is one I did not modify so it is the stock color that Altec used.