Just the Facts (1 Viewer)

[TedO]

I do think DIY sub building is a great project that would yield very good results. I plan on doing one very soon, maybe a sonosub, but I am just starting to research the IB method.

The one thing I find across this forum is speculative comparisons to commercial subs. I have read people posting "my sub SHOULD be better than that sub" seemingly without any actual head to head comparisons.

Being a new sub owner (SVS 16-46cs+) without much experience auditioning different subs, I only know how my sub sounds. These comparisons may be true, but if you don't have a head to head comparison isn't it all just speculation? I would like to learn from the people on this forum but many of the untested comparisons just confuse things. I understand that sub spec's can be compared but there are so many variables I think most of the DIY subs built would have different performance based on construction, material and workmanship.

Accurate information would help me and all the other new DIY's make decisions based on all the hard work and research already done by the experienced people on this board.

TedO

 

[Michael R Price]

I think that when people on this forums make predictions as to how a DIY system performs, they are basing those predictions on fact and experience. For example, we know the driver displacement, enclosure size, and port area of a SVS CS-Ultra, so we can compare that to DIY subs based on those characteristics. (Example: a typical Tempest sub is similar.)

And the performance of a sub can be described mostly with numbers such as frequency response, distortion and group delay. So judging by computer simulations and past experience we can make predictions of the sound of a DIY sub.

In short: No, there are not so many variables. As long as a DIY sub is solidly built and sensibly designed, it can be compared to commercial offerings. And usually beats them.

 

[TedO]

The reason I question it, is mostly because of the construcion materials. I have been looking and I have found one major difference. You can't get a tube similar to SVS's cheaply. Their tube is thicker so I would assume stronger. This and the fact they use Birch for thier end caps not MDF like most DIY's.

So I would assume that would make a difference. Or are the higher grade materials not adding to the preformance of the sub?

 

[Patrick Sun]

It's okay to be a "Doubting Thomas" BUT, until you roll up your sleeves and get to working on one of these projects, after doing the requisite R&D, and understand what commercial subs do, and how to gain that type of performance, and surpass it, there's really nothing anyone can say to you that will convince you otherwise until you can physically experience the performance.

There is a bit of "faith" involved in leaping into the DIY world, and as much hand-holding that many of us here do for the new acolytes, I'm afraid you'll never believe any of the claims until you commit yourself to a DIY project and listen to the final product. Just make sure you start small and work on a project that's been 'tested' by others for being able to produce the performance you desire.

The main thing that SVS subs do is provide the performance in a smaller enclosure than most of us with access to sub drivers can attain (this is due mainly to a proprietary sub driver design). But, we DIYers reap the benefits of costs savings by making due with a larger enclosure and available driver choices for the DIYer.

But if you have money to burn, you can make subs that outperform sub in the $2000 price range for half that amount, and keep the size down (those designs require an expensive driver, and the use of PRs, and maybe a piece of gear to tame the in-room peaks), it's all about your budget and performance requirements. DIY's main appeal is costs savings because you supply the labor and R&D. Most of the mark-up of subs/gear is due to marketing, not the use performance-enhancing materials.

Conventional sonotube material is more than adequate for use with DIY tube subs, and so is MDF. It's always possible to double-layer the sonotube if you'd like, and you can layer up the MDF as well. The cost is minimal.

 

[TedO]

I believe that you can make a sub to rival or surpass a commercially available sub. But I think judging or comparing two sub on spec’s alone in not accurate. We all know how manufactures can manipulate specs on their equipment to make it look better. Take amps for example of this.

In an attempt to build sub to a certain sound quality/output it’s tough to make choices when I read 10 different designs with 3 different drivers all are better than this or that. Maybe I am taking all this wrong and it’s that easy and cheap to build a sub that equals one that costs hundreds or even thousands of dollars. From what I read it seems like $150 driver in the right enclosure is almost as good as a $350 driver in it’s right enclosure.

I will have to dig deeper to see if people are publishing their sub’s actual out put, and use that as comparison

 

[Dustin B]

There is a big difference between manufacture amp and speaker specs and an accurate set of T/S specs on a raw driver.

However, raw driver manufactures do tend to fudge in their favor with these specs. As well T/S specs vary from driver to driver within the same make and model.

If a manufacturer gets their driver independantly dumaxed you can be pretty confident in the T/S specs. Then with the software that is out there and the experience of some of the members here you can very accurately determine how a sub will perform.

So in the end a proper set of T/S specs are many many times more valuable than any speak or amp specs any main stream manufacture supplies.

 

[Jack Gilvey]

It's tough to convince anyone (although that's not all that important to DIY folks) about performance since you won't see a reassuring review of a DIY sub in a magazine. For this reason, comparisons to commercial subs are indeed speculation, as they can't be tested under identical conditions. However, it is possible to have very informed specuation. You'll need to do lots more research before you'll see what "just the facts" are, though. And, of course, DIY is not for everyone. If you're really unsure, stick with the SVS.

 

[Greg_R]

Didn't Noussaine review & measure a few DIY designs? (I seem to remember 2 IB designs and the older Stryke design)...