OT12 for 12 volt system.

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Seth
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Re: OT12 for 12 volt system.

#16 Post by Seth »

monekh wrote: Sat Jan 08, 2022 12:33 pm Im currently putting together a 12v system which will be mounted on a steel trailer and pulled by bicycle...
Hey monekh, love the project :thumbsup:

Other than being 12v and trailered behind a bicycle, what expectations do you hope to fulfill with this system? Is it meant to broadcast as far as possible? Provide the fullest sound? Chest pounding bass?

Would it get towed to location and operate mostly while stationary or will it primarily be used while riding around? How far away from the trailer are people that are actively listening to the music potentially going to be?
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

monekh
Posts: 83
Joined: Mon Mar 31, 2014 5:56 pm
Location: London, UK

Re: OT12 for 12 volt system.

#17 Post by monekh »

thanks everyone for your input and sound advice.

monekh
Posts: 83
Joined: Mon Mar 31, 2014 5:56 pm
Location: London, UK

Re: OT12 for 12 volt system.

#18 Post by monekh »

Seth wrote: Mon Jan 10, 2022 1:46 am
monekh wrote: Sat Jan 08, 2022 12:33 pm Im currently putting together a 12v system which will be mounted on a steel trailer and pulled by bicycle...
Hey monekh, love the project :thumbsup:

Other than being 12v and trailered behind a bicycle, what expectations do you hope to fulfill with this system? Is it meant to broadcast as far as possible? Provide the fullest sound? Chest pounding bass?

Would it get towed to location and operate mostly while stationary or will it primarily be used while riding around? How far away from the trailer are people that are actively listening to the music potentially going to be?
Hi Seth,

Thanks!

The project is to make a sound piece based on field recordings and music in and about the City Marseille. This work is gonna be played in some outdoor public spaces and there is some money to build this system to do that. There's no vehicle or power source available so the decision was to go 12v and give up on a stereo representation but try and make something that sounds great anyway. After the project the system and trailer will be left with a community centre in Marseille for outdoor events primarily playing hiphop and electronic music to small crowds (probably between 20 and a 100people.)

So in a sense we need enough volume and low end for the second intention, and also a full and quality sound for our first objective.

We had already considered that the original plan would be too heavy for a very very mobile function, so its definitely more about getting to any given square, cave, or courtyard in Marseille and playing music for some hours then it is about riding playing music with a bicycle entourage. :)

building the OTop 15 is definitely better in that its lighter and cheaper then my original plan. Bill said it would go lower than the cubo plus an OT12 , but i wonder if it could possibly be as loud overall? Another concern is the high end will be blasting into peoples knees. ( unless modified that the horns/ compression drivers are ontop of the cab rather than in its mouth). Also annoyingly somethings like the amps have already been acquired so it isnt the easiest thing to make a shift to a new plan entirely rn.

Im gonna bring the suggested OTop15 option to the group today and see what we decide.

If people do decide to go ahead with the original plan I'd' also really welcome any suggestions of a DSP to use with a 12volt system ( itd be just for the Otop12 - the cubo is fine with the controls on the amp i think ). I think we dont have the time or knowhow to make up the passive crosovering in the end.

Ta,

monekh
Posts: 83
Joined: Mon Mar 31, 2014 5:56 pm
Location: London, UK

Re: OT12 for 12 volt system.

#19 Post by monekh »

Seth wrote: Mon Jan 10, 2022 1:46 am
monekh wrote: Sat Jan 08, 2022 12:33 pm Im currently putting together a 12v system which will be mounted on a steel trailer and pulled by bicycle...
Hey monekh, love the project :thumbsup:

Other than being 12v and trailered behind a bicycle, what expectations do you hope to fulfill with this system? Is it meant to broadcast as far as possible? Provide the fullest sound? Chest pounding bass?

Would it get towed to location and operate mostly while stationary or will it primarily be used while riding around? How far away from the trailer are people that are actively listening to the music potentially going to be?
Ps. i guess it doesn't need to broadcast too far no, but should be full and loud enough for that size crowd around it to really enjoy themselves.

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Seth
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Re: OT12 for 12 volt system.

#20 Post by Seth »

So, I have nowhere near the expertise Bill possesses, nor the experience Bruce has. But, I did stay at a Holiday Inn Express last night.

If I understand you correctly, the primary use will be towing it to a location for a crowd of 20-100 people listening and dancing. Ease of mobility for storage is also a priority.

I like Bruce's recommendation for extension AND I like Bill's focus on sensitivity. For every 3dB increase in sensitivity, you'll get the same output with half the power... be able to run twice as long on a battery charge. (Not exactly, but loosey goosey talk, for the sake of conversation). I also agree that the sub enclosure you mentioned wouldn't be as effective as other options.

My recommendation is no better or worse than the others given. Just another option and opinion to ponder. If it were me, I'd build a full width T48 to put that 15" driver in (yes, the T/S specs are acceptable). I'd put it on the trailer lengthwise, yet firing to one side or the other, so the cab width is maximized in a vertical orientation without affecting the needed width of the trailer, keeping it minimized to as little as 24"/61cm wide (plus tires 'n stuff). Sonically, it won't make a difference which direction the mouth faces. I'd put casters on the end of the cab that faces rearward so the trailer could be tilted rearward until completely upright up on it's end, easily wheeled around tighter spaces, and take up a smaller footprint when stored. I'd put a top-hat in the top of the T48 and another in the side that faces up when in trailer mode so that you can pole mount your mid/high cab(s) with the trailer in either orientation and get the mid/high cab(s) above the crowd. Personally, I'd just build two 2x6" loaded SLA Pro's for tops. They're an easy build and they can be mounted one on top of the other and aimed the same direction for better throw when needed, splayed outward for wider coverage when needed, or aimed 180º for coverage in two directions. Or, you could even put them on standard speaker stands, left and right, for a more traditional "stage" type of venue/location.

I'd put your mono amp on the T48 and bridge the other amp for 2 channel output, one to each SLA Pro 2x6. I have used and like the Dayton Audio DSP-408 for signal processing. But, Mini DSP 2x4 is very popular too. I just haven't used it. I've seen some others pop up on the market from some of the car audio speaker/amplifier companies. But, in reading through their functionality and user interfaces, I don't think I'd appreciate them after using the Dayton unit. But again, I haven't used them so I really can't say for sure.

This plan would give you great extension, fantastic sensitivity, and excellent versatility. It wouldn't be as compact as the other options mentioned. But, sound wise, it would be the most impressive option, IMO. Especially capitalizing on, and maximizing the potential of the amplifiers on hand, too.

Whatever you choose to build, I highly recommend just building and using the passive crossovers in the plans (component values appropriately modified to accommodate your driver if need be). The parts are easy to source, they're easy to build, and ultimately will make it much simpler to get a sound you'll love. I get the allure to want to run everything on it's own amp channel. It's just not worth it in this case. But, feel free if it's what you really want to do.

If you have no idea what the Holiday Inn Express has to do with anything... Playlist: Holiday Inn Express commercials :lol:


Side note about the Dayton DSP-408: There's a Bluetooth option (not included) that gives tunability via smartphone (versus the standard method of PC via USB) and also allows Bluetooth music streaming... no other source needed. Could be handy.
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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tactix
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Location: Providence, RI
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Re: OT12 for 12 volt system.

#21 Post by tactix »

monekh wrote: Sat Jan 08, 2022 12:33 pm Hello all,
Im currently putting together a 12v system which will be mounted on a steel trailer and pulled by bicycle
Monekh,
I've wanted to build something similar to what you have planed for some time, so I'm hopeful you will move forward with the project and start a build thread. I'd follow it with much interest. Great project!
Seth wrote: Tue Jan 11, 2022 12:01 am
My recommendation is no better or worse than the others given. Just another option and opinion to ponder. If it were me, I'd build a full width T48 to put that 15" driver in (yes, the T/S specs are acceptable). I'd put it on the trailer lengthwise, yet firing to one side or the other, so the cab width is maximized in a vertical orientation without affecting the needed width of the trailer, keeping it minimized to as little as 24"/61cm wide (plus tires 'n stuff).
Riffing off Seth's suggestion, given that they will presumably be building a custom trailer to carry this rig, might it not also be possible to keep the floor of the trailer open and mount the T48 at an angle with the mouth facing the ground to use the road as boundary reinforcement similar this
Image as is recommended when working in open areas viewtopic.php?f=10&t=398&p=2775&hilit=s ... ding#p2775?

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