Buy first to find out what driver you need?

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matt ristrom
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Buy first to find out what driver you need?

#1 Post by matt ristrom » Sat Jul 13, 2019 4:04 pm

OK - so Bill's stuff pops up a lot and it caught my interest. However, what seems to be absent, is actual driver information BEFORE the ordering process.

And before I go into that - are we a bunch of 5 year olds??? Why do I have to endure a swarm of "smilies" off to my right as I try to type??? JFC

So I do a lot of pro audio stuff and have an enormous pile of various drivers. What I will NEVER do is buy plans from Bill without knowing what drivers the plans are designed for. Why the drivers for each project have to be a secret - or why this information is so intensely difficult to find is maddening. There is a limit to how much work I will do to give someone my money. I was ready over a week ago to order some plans and try a design. But before I send $15, or whatever, I will need to know which drivers I will need for these cabinets. In fact, the first plans I buy will be determined by which plan has drivers listed that I already own.

Has anyone else found a solution to this? Is there a driver list by tuba/titan model?

Having to dig for information on this forum reminds me of the way our potus tweets instead of doing professional press conferences. From someone that typically deals with engineers and professional sound companies this seems like a big red flag. It would be helpful to have a website where this information is listed and easy to find.

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Bill Fitzmaurice
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Re: Buy first to find out what driver you need?

#2 Post by Bill Fitzmaurice » Sat Jul 13, 2019 4:14 pm

The projects aren't designed for specific drivers, they're designed for drivers with Thiele/Small parameters that fall within a given range and, in the case of horn loaded tops, a rising response in the midrange. For that reason there's no list of drivers that may be used in a specific design, as that list could have dozens of entries.
This is covered in the FAQs. Specifically:
Please do not ask "Do you have a cab I can use my driver in?". When choosing a cab your priorities are frequency response and cab size, so that's what you base your choice on. You then use a driver with appropriate specs. If you happen to have one on hand fine; if not, buy one. Trying to make use of an on hand driver to save a few bucks and ending up with a cab that doesn't meet your needs is a bad idea.

matt ristrom
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Re: Buy first to find out what driver you need?

#3 Post by matt ristrom » Sat Jul 13, 2019 4:19 pm

Pretend I said "Thiele/Small parameters list" then. How about providing the T/S parameters for each tuba and titan design so we can figure out which drivers we need?

Or, as I posted, do I have to buy plans first - and then you tell me what the T/S parameters are?

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Re: Buy first to find out what driver you need?

#4 Post by matt ristrom » Sat Jul 13, 2019 4:23 pm

To be clear - I am not going to throw money at you until I know what drivers I will need. And because I have never used one of your designs I am also not going to risk having to buy drivers I do not already have.

I am willing to buy one of your designs but my intent is to pick a design that I already have drivers for. And I have a LOT of drivers so that should not be an issue. What is missing is you seem to be hiding the T/S driver specs for each design.

Do you have the T/S parameters listed somewhere or do I have to buy first and hope?

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Re: Buy first to find out what driver you need?

#5 Post by rfauske » Sat Jul 13, 2019 4:31 pm

If you list what you have or check the sbl charts most have the driver specified.

If you list what cab you are thinking of most will be happy to say what drivers fit. But looking for a cab for a driver is not much use in as the cabs have totalt different frequency response and output.

The thing you need to find is a cab that fits your use and not one that fits your driver..

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Re: Buy first to find out what driver you need?

#6 Post by matt ristrom » Sat Jul 13, 2019 5:41 pm

You should not have to pick a cabinet first if you already own suitable drivers. Out of almost a dozen different sub designs I should be able to find a design that I already have drivers for. Nobody is responding to the big elephant in the room - Bill is not even listing the T/S specs unless you pay him first. In fact, I have not even seen where there are driver sizes listed for each design (8", 12", etc.) It is backasswards to not find out what driver you need until after you pay for plans.

Am I am the only person here that has an issue with this?

rfauske - Thanks for mentioning the SPL charts. I will see if there is any useful information there but I am already getting a lot of feedback from other pro audio guys that have tried Bills designs and suggested I save my time and plywood. FYI - I appreciate the "buy the design based on specs" but I would also not buy a car by telling the dealer to just give me something that will go at least 75mph for 300mls. I would want to pick the color, number of doors, etc. And in this case I already have the motor.

I think I am in the wrong place for pro audio.

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Re: Buy first to find out what driver you need?

#7 Post by matt ristrom » Sat Jul 13, 2019 6:09 pm

rfauske - where are these SPL charts you talk of? Are you just talking about the chart showing a single comparison for each design?

If that is all there is I would have to go through and make my own list with one driver for each design. I guess I could then look up the TS for that driver myself and then compare other drivers I have to see if they are comparable. But don't some of these designs allow you to choose between different drivers: 1x15, or 2x12, or 1x10, etc. ??
Are we supposed to buy plans for a design without even knowing what size the driver will be? Or how many drivers will be needed ??

How about this for an idea Bill:
Box Design: Super Dooper Tuba 900
Freq Response: 22 - 120hz, down 10db at 22hz (or show your fancy graph comparing it to another brand)
Driver options for this design: 1x12 or 1x15 (now we know what the driver options are and the box size options)
Box sizes by driver option: (now we can figure out what we want to build based on what fits on our truck or in our venue)
TS parameters by driver option: (now we can figure out what driver we want to order, or if we have drivers in stock for this design)

If you listed the TS driver parameters for each choice, audio pros with piles of drivers could find designs they like that they already have drivers for. You would not be giving away your design secret (a folded horn? hmm. big secret). The only info you would be giving away are the specs the driver manufacturer is willing to let you have whether you buy their driver or not. And for the DIY types that don't want to bother - they can simply order whatever driver you spec and not worry about it.

I have almost exhausted the amount of energy I am willing to spend here before I turn right around and head back to the pro audio camp.

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Re: Buy first to find out what driver you need?

#8 Post by Bruce Weldy » Sat Jul 13, 2019 7:17 pm

Since you finally listed some parameters that you want, then it looks like a Tuba 60 would be the appropriate cab.

It uses the Lab 12 or Lab 15 and here's the specs for a driver for that cab.

If you can’t get Eminence the acceptable range for pro-sound driver T/S specs is Fs 20 to 30Hz, Vas 100 to 150L, Qts .30 to .40, xmax no less than 10mm. Do not use hi-fi or auto sound drivers, they will not withstand the high throat pressure of the T60 design.

See, that wasn't so hard....

We do indeed try to help.

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Re: Buy first to find out what driver you need?

#9 Post by J_Dunavin » Sat Jul 13, 2019 7:21 pm

SPL charts-

The driver choice is really a moot point.
Go over the designs, choose based on coverage and SPL needs.. we can help with that.
Buy some plywood, make some dust, follow the plans and enjoy ;)
I love my set up! Six DR20s and six T45s! They sounds absolutely fantastic, nothing can come close dollar for dollar , pound per pound.

Sure.. there’s other DIY sites out there, but none with this knowledge base and all around nice group.
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Re: Buy first to find out what driver you need?

#10 Post by ACUA » Sat Jul 13, 2019 8:28 pm

I agree with you, there is some strange angles to things here. The whole philosophy is different here, if you are not willing to try to see things from this perspective it may not be the place for you. As far as getting advice from other sound guys about saving your time and money by avoiding building Bill’s speaker designs, well you do you man and good luck to you. I have been here for over two years and I have spent a lot of time studying and trying to learn. It has been a steep learning curve and I claim to know a lot of stuff.

Are you going to discredit this whole thing if you find out that somehow none of the current drivers you have fit the available plans, or if one does fit but it does not perform how you want it to? The reason things are this way is to ensure your not set up for failure.

I feel like I understand why things are the way they are at least as far as why the T/S specs are in the plans, the correct philosophy, to me, is to have a need, find the plan that best satisfies the need, buy and build, then enjoy the tool.

I see your point, you have every right to be aggressive and caustic about how you invest your money. It is a risk for sure, you have some gear and want to put make use of it. I get it, it would be easiest for you if the driver requirements were given and more disclosure was provided here, fair enough. But uh this stuff is complicated, if it was not then it would be mainstream. Well that is how I see it, at least to some extent. Some suffering on the new guys part helps solidify the value of this place speaker plans and all.

I would challenge you to study up here a little bit, be patient, look at the why for these horn loaded designs. What is the pay off, there is magic here but it is not for everyone honestly. For me I have a diy attitude and am on a tight budget. I wanted bass extension below the typical PA subwoofer available to average consumers. This ticks all the boxes for me and I have had great success with these products.
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Re: Buy first to find out what driver you need?

#11 Post by ketoet » Sun Jul 14, 2019 3:57 am

I also found bill's designs in search of a cab that i could build for the drivers i had laying around. I ended up on this forum and got some great help from the people here . I never used the drivers i had because they didn't work in the designs i actually had a use for. They do work in the jack 15 but that's not a cab that's suits my needs best.
I eventually bought the whole cd of plans and have build several designs for several different uses.
It's however your money and you spend it how you see fit. I never had any regret sending some of mine to bill.
But that's of course just my opinion

Greetz ketoet
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matt ristrom
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Re: Buy first to find out what driver you need?

#12 Post by matt ristrom » Sun Jul 14, 2019 1:48 pm

Bruce - I did not list any specs. I was suggesting a way that Bill could actually list the driver options and T/S recommendations for each cabinet in a way that made it easy for engineers or pro audio people to find right away. I don't think Bill has a "Super Dooper Tuba 900" designed yet - just showing an example of what might be handy for pro audio guys that are thinking about one of his designs.

This forum seems to be a part time job/hobby/social media for a lot of you. I appreciate spending weeks/years wading through this stuff on the forum might be fun for some of you but I do not have that kind of time. I am used to working with JBL, EV and EAW where you have PDF's with all the information you need including cabinet size, driver specs, etc. and you can get the information you need and make decisions in a matter of hours.

Good luck to all of you. Moving on.

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Re: Buy first to find out what driver you need?

#13 Post by ACUA » Sun Jul 14, 2019 2:43 pm

Well since it was not obvious, you did figure it out in the end. This product is not marketed for the big time suit that I feel like you claim to be, funny how big time you claim to be and yet can’t spend the lousy $15 asked for a set of plans!!! If you ain’t got time for this forum than you certainly ain’t got time to build these sophisticated speakers.
People in your shoes don’t waist their time in diy dive bar forums like this. No, they just go blow a ton of money into whatever company has a reputation for the best product, they don’t have time to study and research. I will join your band wagon in a heart beat, just tell me where I can get equipment cheaper than here that actually performs as good or better!!!!

Ask any of those big sound companies for subs that play out to 25hz. Or ask them for any data or schematics for you to diy reverse engineer their stuff. Go ahead and pay the premium price for their equipment. Or start your own company and design your own loud speakers. You are clearly smart enough to do better than this place
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Re: Buy first to find out what driver you need?

#14 Post by Votandrums » Mon Jul 15, 2019 7:01 pm

Honestly man its 15 bucks for plans. Chances are buying the plans and finding out you need to buy drivers is still gonna be cheaper than buying a commercially made sub in my opinion. Besides you can look through thr forum and get a good idea of what drives are reccomended. Look at thr specs on those drivers and compare to thr ones you have. I'll have maybe 500 bucks in two t-48's. That's with buying new premium drivers. Tell me where your gonna get the kind of output they have for under a 1000 bucks. So spend the 15 dollars and get building.

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Re: Buy first to find out what driver you need?

#15 Post by jimbo7 » Sun Sep 01, 2019 12:40 pm

I wish I would've seen this thread before the op had a hissy fit and stomped off like a "5 year old" lol

A reminder that not every deserves help and to not feed the trolls
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