NEW BUILD - Omni 15 Tall Boy in New Zealand

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Seth
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Re: NEW BUILD - Omni 15 Tall Boy in New Zealand

#136 Post by Seth »

For real though, my guess is one of those T-nuts you have holding the driver on either didn't get tightened enough and/or backed off. Highly recommend lock nuts on lock washers, or double nutting those.
Screenshot (82).png
Build in process - 2 WH6, one Alpha 6a loaded, one PRV Audio 6MB250-NDY loaded

Two 2x6 shorty SLA Pro's
One T39, 16", 3012LF loaded
Tall AutoTuba, 20" wide, 2x 8" MCM 55-2421
TruckTuba, 8½" wide, 2x 8" MCM 55-2421

Bruce Weldy
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Location: New Braunfels, TX

Re: NEW BUILD - Omni 15 Tall Boy in New Zealand

#137 Post by Bruce Weldy »

Seth wrote: Tue Dec 15, 2020 9:32 pm Just remove the offending string from the bass guitar and call it done. :D
This is actually an excellent idea......In fact, shouldn't all bass guitars just have an E and A string? And no frets past the fifth one? :mrgreen:

6 - T39 4-25" 2-22" 3012LF
4 - OT12 2512 Melded/NSD2005
1 - T24
2 - XF210


"A system with a few knobs set up by someone who knows what they are doing is always better than one with a lot of knobs set up by someone who doesn't."

Grey Owl
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Location: New Zealand, User 1603

NEW CONTACT - Omni 15 Tall Boy in New Zealand

#138 Post by Grey Owl »

Hola compadres!
I'm back in the house after 6 months away................. :hyper:
Been in good health just bin doing other stuff in other places.
Now it's deepest winter here i.e. wet, windy and cold (currently down to a low of 13C in our open seas maritime climate) I have to make an effort to track down the elusive buzz in the new O15TB cab. :slap:
Wifey says change bass i.e. fretless, and does it still buzz......?? Haven't tried that yet. :bull:
Still, I'm glad to be back here.
Cheers All
You have two ears and one mouth. Use them in the same ratio!!

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Seth
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Re: NEW BUILD - Omni 15 Tall Boy in New Zealand

#139 Post by Seth »

David!!! Welcome back brother :thumbsup:

I read a post the other day that reminded me of your buzz dilemma. It was this thread about a buzzing sound that turned out to be an issue with the amp instead of the speaker cab. So, maybe your wife's onto something :idea:

I assume our Summer Solstice up in the Northern Hemisphere is your Winter Solstice... 6 more days.
Last edited by Seth on Tue Jun 15, 2021 4:00 pm, edited 1 time in total.
Build in process - 2 WH6, one Alpha 6a loaded, one PRV Audio 6MB250-NDY loaded

Two 2x6 shorty SLA Pro's
One T39, 16", 3012LF loaded
Tall AutoTuba, 20" wide, 2x 8" MCM 55-2421
TruckTuba, 8½" wide, 2x 8" MCM 55-2421

Grant Bunter
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Location: Ilfracombe Queensland Australia
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Re: NEW BUILD - Omni 15 Tall Boy in New Zealand

#140 Post by Grant Bunter »

Welcome back!
Built:
DR 250: x 2 melded array, 2x CD horn, March 2012 plans.
T39's: 4 x 20" BP102 , 2 x 28" 3012lf.
WH8: x 6 with melded array wired series/parallel.
Bunter's Audio and Lighting "like"s would be most appreciated...

Grey Owl
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Joined: Fri Mar 20, 2009 10:38 pm
Location: New Zealand, User 1603

Re: NEW BUILD - Omni 15 Tall Boy in New Zealand

#141 Post by Grey Owl »

Ta muchly.
Yep seasons turn here Wednesday 21st June and then it's a long long run to Summer!!!!!
Can't wait.
Thankfully we don't get snow here in the Auckland region as we are at sea level +25 metres or thereabouts.
You have two ears and one mouth. Use them in the same ratio!!

Grey Owl
Posts: 215
Joined: Fri Mar 20, 2009 10:38 pm
Location: New Zealand, User 1603

That Elusive Buzz - I think I may have it - Maybe!! - Omni 15 Tall Boy in New Zealand

#142 Post by Grey Owl »

Afternoon All,
We're back in COVID "lock down" agin so, took time out to properly investigate what's going on. :fingers:
Pics attached for your edification.
= back removed
= thought it could be a rattling loose wire etc. Everything tightened, resoldered, stapled cardboard caps on long run wires.
= tightened all speaker bolts etc
= tweeter turned off
= sound appeared loudest in the midrange.
= removed Alpha 6CBMRA
= checked speaker. Pics show what I reckon is definitely a gap between the dust cap & coil. Came adrift? Your thoughts please? :broke:
= Why he thinks??
= looked at my cutting of the plug. Looks quite a bit off on one side. Actually, more than a bit
= Didn't notice that at the time!
= using a divider with pencil scriber, marked the required size circle and I was oversize as the pic clearly shows. :slap:
= Thought to meself, ahhh that's the phantom buzz right there :hyper:
= ground down & curved plug edges to be safe just in case
= to ensure (double braces) of enough space between plug and dustcap, I also added an additional layer of speaker tape
= all-in-all, the cab back came off & on 3 times
= when tested with mid removed, no buzz :D
= reassembled after adjustments and tested loud with good quality jazz & dub tracks; sounded good
= I've taken 4 or 5 vids to show you the tests I did but not sure how to load them as I can't resize them.

Thing is boys, my wife may have been on the right track all the time; using my fretless (whilst it's low gain), no buzz.
Fretted low B however, it's definitely a bit buzzy down low. Mibbee the response sensitivity of the OT15TB is producing clarity that I could not hear before?? It was built as a 4 string low e but I restrung it to low B.
Perhaps a visit to my luthier guy is needed.

Anyone else had mysteries like this before? :confused:
Al thoughts appreciated.
Cheers
:feedback:
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You have two ears and one mouth. Use them in the same ratio!!

Grey Owl
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More pics: NEW BUILD - Omni 15 Tall Boy in New Zealand

#143 Post by Grey Owl »

Further pictures.
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You have two ears and one mouth. Use them in the same ratio!!

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Tom Smit
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Re: That Elusive Buzz - I think I may have it - Maybe!! - Omni 15 Tall Boy in New Zealand

#144 Post by Tom Smit »

Grey Owl wrote: Wed Oct 06, 2021 12:12 am
Thing is boys, my wife may have been on the right track all the time; using my fretless (whilst it's low gain), no buzz.
Fretted low B however, it's definitely a bit buzzy down low. Mibbee the response sensitivity of the OT15TB is producing clarity that I could not hear before?? It was built as a 4 string low e but I restrung it to low B.
Is the action that low? Perhaps you need to raise the action a smidge.
Oh, and one more thing: is there clearance between the midrange baffle RH lower corner and the front/rear brace?
TomS

tallevan
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Joined: Sun Oct 20, 2019 12:15 pm
Location: London, England

Re: NEW BUILD - Omni 15 Tall Boy in New Zealand

#145 Post by tallevan »

Hiya.

The gap in the dust cap on your mid driver looks exactly like mine. I don't think it's a problem.

I built a OTB12 with two 10" drivers, and have a sympathetic resonance at 133hz.
It feels like a really loud golden tone, for any upright players out there.
I can't find any structural defect, I've swapped out the drivers and taken out everything except the two 10" drivers.
Also increased the bracing (joining the top and bottom structures) and removed the back.

Even then, same resonance.
Bill and the members here were very helpful, but I've built a couple of Simplexx and Jack 10 boxes for the drivers instead.
If it's not a delamination, I can only think it's a natural resonance for my particular build. Like ringing a bell.

Could be wrong, of course.

tallevan
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Re: NEW BUILD - Omni 15 Tall Boy in New Zealand

#146 Post by tallevan »

One thing I remember, I thought the plug might have been quite close to the dustcap of the mid driver on my build.
I feared with the excursion it might buzz against it, so I thinned it by about a mil.
Ply varies in thickness.

That wasn't it.

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Seth
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Re: That Elusive Buzz - I think I may have it - Maybe!! - Omni 15 Tall Boy in New Zealand

#147 Post by Seth »

Grey Owl wrote: Wed Oct 06, 2021 12:12 am I've taken 4 or 5 vids to show you the tests I did but not sure how to load them as I can't resize them.
Upload them to YouTube then paste the link here.
Build in process - 2 WH6, one Alpha 6a loaded, one PRV Audio 6MB250-NDY loaded

Two 2x6 shorty SLA Pro's
One T39, 16", 3012LF loaded
Tall AutoTuba, 20" wide, 2x 8" MCM 55-2421
TruckTuba, 8½" wide, 2x 8" MCM 55-2421

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