DIY Budget Cab! How Bad Could It Be?

[charlie monroe]

My thought is ditch the horn

 

[Dean N]

How bad could it be? Actually, quite crappy.



Hey, you asked.

 

[Downunderwonder]

The only cab to look to copy is the 410 Eden in 1/4 volume with 1/4 port area and same port length.

 

[CoffeeLove]

How bad could it be? Actually, quite crappy.



Hey, you asked.

Haha, true, but I am going with amazing.

 

[Tim Skaggs]

I can tell you this from multiple experiences; a really well designed cabinet tuned properly to the drivers in the cabinet, even if the drivers aren't super top notch quality, can sound great.

On the other hand, a super top notch quality speaker, the best money can buy, will sound like crap in an incorrectly sized &/or incorrectly tuned cabinet.

All you have to do is build / tune the cabinet properly for your speakers, and you'll have something....

 

[bobcruz]

While beyond my scope of knowledge, this is all good stuff. I will likely find the dimensions/design of a few popular 110 cabs and build to similar specs. I will be using an Eden driver from a D410XLT.

I already have a pair of small baffles, rubber feet, a horn/tweeter, speaker wire, and input plate, most of which came from an old/blown PA speaker.

I am not certain what to do about the crossover. I found one designed for general use for $15.

1 Passive 2 Way Crossover Network 800 Watts Car Home DJ Audio EMB CX-5 | eBay

Thoughts?

Eden never used a two-way crossover in the XLT cabs. The 10s run full range and the tweeter is high-passed at 3500 Hz with a 3d order filter (a fairly steep 18 dB/octave slope). You'd probably be better offer without a tweeter. Bob

 

[CoffeeLove]

Eden never used a two-way crossover in the XLT cabs. The 10s run full range and the tweeter is high-passed at 3500 Hz with a 3d order filter (a fairly steep 18 dB/octave slope). You'd probably be better offer without a tweeter. Bob

That is some good info. I do like having some top end in my cabs, thus thinking the tweeter as necessary. It sure would make things easier to skip the tweeter.

 

[micguy]

Bag End has made bass cabs rated to go down to 8 Hz. Not that I need to go that ridiculously deep.

From their datasheet (this is for a 21 inch subwoofer)

Frequency Response: 60 Hz to 250 Hz ±3 dB 8 Hz to 95 Hz ±3 dB with external Infra™ Integrator

So, that one is a 60Hz box that you can eq (with siginificant risk of peril) down to 8Hz. It also doesn't go above 250 Hz, which ain't gonna sound good on your bass.

The do have spl limit specs on their other cabinets in this series. 10 Hz limits are typically 25dB or so below what they'll do further up. 25 dB lower at 10 Hz means...you won't hear the 10 Hz that it puts out. You might hear some "complaints" from the driver moving that much, but you won't hear the 10Hz signal.

I said I haven't seen a commercially available bass guitar cabinet that will go down to 41 Hz.
There are plenty of PA cabinets that do. This is a PA box, or could be used in the home for theater stuff, it's not a bass guitar cabinet.

 

[BadExample]

Why?

As Andy indicated that won't do much for us. They've used these types of systems for some interesting things. Teaching deaf children to dance to the feel of music and military simulators like helicopters. It's been months since I read up on this stuff, but I think they claim subharmonics of bass are beneficial. I'm not convinced. Before I play loud(er) I'll probably HPF my (old) BE SB18. They have newer models for MI use that have a more reasonable frequency response (like 46 to 4 KHz without tweeter or up to 16KHz with). Mine's rated at 8 to 2 KHz. I like the tone, but it would be too dark for a lot of people (I love the tone with a 15" BP1525 "top" bi-amped). The current 18's sold for MI are 8 to around 100Hz, sold as a subwoofer with or without the infra amp (previously ELF) built in. I think any of the above would be best HPF'd for the funamental or the first harmonic. I'll let you know when I get some time... Before that I'll be adding a sealed midrange to the 15 in a smaller cab.

(as it reminded me of me in the early 70's)

It reminded me of my bell bottoms that were colored like an American flag and a puffy "balloon" sleeved purple shirt with a ridiculously long pointy collar. I just threw up a little in my mouth. Two separate items, never worn together. Nothing like the retro-70's stuff from a few years back. The past is in the past for a good reason!

 

[Paulabass]

Before there was computer software, I designed and manufactured small format touring p.a. enclosures. I sold LOTS of them.
We used vague T/S parameters, and a sliderule (google it). Mostly, we used our ears, and made lots of prototypes. Our listening room (no fancy anechoic chambers) was the warehouse. Then we had factory reps from Gauss ,and JBL come down and bring a trunkfull of drivers. More experimenting, more prototypes.
Bottom line, with some decent plans, you CAN make a serviceable cab. You can even eyeball a serviceable cab. It may not be perfect, but you may invent the next big thing.
Note- I built one cool low freq. unit that the port and the cab front were PERFECTLY out of phase, and we got almost complete cancellation. OOPS!

 

[BadExample]

From their datasheet (this is for a 21 inch subwoofer)

Frequency Response: 60 Hz to 250 Hz ±3 dB 8 Hz to 95 Hz ±3 dB with external Infra™ Integrator

So, that one is a 60Hz box that you can eq (with siginificant risk of peril) down to 8Hz. It also doesn't go above 250 Hz, which ain't gonna sound good on your bass.

The do have spl limit specs on their other cabinets in this series. 10 Hz limits are typically 25dB or so below what they'll do further up. 25 dB lower at 10 Hz means...you won't hear the 10 Hz that it puts out. You might hear some "complaints" from the driver moving that much, but you won't hear the 10Hz signal.

I said I haven't seen a commercially available bass guitar cabinet that will go down to 41 Hz.
There are plenty of PA cabinets that do. This is a PA box, or could be used in the home for theater stuff, it's not a bass guitar cabinet.

That's why I said "has" made, as in the past. The current 18" sub is still rated down to 8 Hz. Carvin also made bass cabs rated down to 30 Hz. IIRC it was -6bd @30hz, then a -3db rating for 40 up to whatever... something like that. Also in the past, but more recent

Ah, here it is, distorted memories:
- Reproduces Frequencies from low B (28 Hz to 22k Hz)
- Frequency response 35 to 18kHz +/- 5DB
BRX10.2 Bass Speaker Cabinet

That was available up to a few months ago. No deviation claims from 28 to 35 Hz.

I'm not saying anything below 30 Hz is an improvement in sound quality, or that HPF above the low B fundamental will not improve the overall sound and safe volume levels. I'm just saying this stuff exists.

 

[BadExample]

sliderule (google it)

Don't have to. My dad made me learn to use one. I've got his slide rule cuff links and tie tack. Birth control jewelry!

 

[micguy]

That's why I said "has" made, as in the past. The current 18" sub is still rated down to 8 Hz. Carvin also made bass cabs rated down to 30 Hz. IIRC it was -6bd @30hz, then a -3db rating for 40 up to whatever... something like that. Also in the past, but more recent

Ah, here it is, distorted memories:
- Reproduces Frequencies from low B (28 Hz to 22k Hz)
- Frequency response 35 to 18kHz +/- 5DB
BRX10.2 Bass Speaker Cabinet

That was available up to a few months ago. No deviation claims from 28 to 35 Hz.

I'm not saying anything below 30 Hz is an improvement in sound quality, or that HPF above the low B fundamental will not improve the overall sound and safe volume levels. I'm just saying this stuff exists.

The spec from Carvin says 35 to 18Khz, and a 101 dB SPL sensitivity, in a size that, frankly, having done a lot of calculations on such things...I don't believe. I have a single 10 box that does go to 40 Hz (-3dB), is very close to that size, and has a sensitivity of 91dB SPL. 10 dB more sensitivity with the same bandwidth in the same size box? Not gonna happen, regardless of what's been claimed.

 

[Rick James]

The spec from Carvin says 35 to 18Khz, and a 101 dB SPL sensitivity, in a size that, frankly, having done a lot of calculations on such things...I don't believe.

35 to 18 khz is possible, so is 101 dB sensitivity. What's not possible is to do that at +/-5dB. That would make sensitivity at 35 hz 96 dB, which no 210 on earth can do, unless it's an 18 cubic foot or larger folded horn PA sub.
As for the Bag End, they use a Linkwitz Transform to reach very low. But Linkwitz doesn't get around Hoffman, as in Hoffman's Iron Law. It goes low with very low sensitivity, so it needs a lot of power, and the driver will run out of excursion long before the 8 hz output is useful outside of a living room home theater.

 

[agedhorse]

Before there was computer software, I designed and manufactured small format touring p.a. enclosures. I sold LOTS of them.
We used vague T/S parameters, and a sliderule (google it). Mostly, we used our ears, and made lots of prototypes. Our listening room (no fancy anechoic chambers) was the warehouse. Then we had factory reps from Gauss ,and JBL come down and bring a trunkfull of drivers. More experimenting, more prototypes.
Bottom line, with some decent plans, you CAN make a serviceable cab. You can even eyeball a serviceable cab. It may not be perfect, but you may invent the next big thing.
Note- I built one cool low freq. unit that the port and the cab front were PERFECTLY out of phase, and we got almost complete cancellation. OOPS!

Tough way to make a living, eh?

 

[agedhorse]

The spec from Carvin says 35 to 18Khz, and a 101 dB SPL sensitivity, in a size that, frankly, having done a lot of calculations on such things...I don't believe. I have a single 10 box that does go to 40 Hz (-3dB), is very close to that size, and has a sensitivity of 91dB SPL. 10 dB more sensitivity with the same bandwidth in the same size box? Not gonna happen, regardless of what's been claimed.

Yup, as the box size decreases, the tradeoffs between low frequency extension, maximum SPL and sensitivity become a battle of the variables. The goal is to maximize the tradeoffs the best way possible, principally by making good choices and not giving up any AVAILABLE performance on bad choices, bad practices or lossy parts.

 

[BadExample]

And I paid the weight penalty on that old bag end. About 90#. Their newer stuff is all lighter than that I think. Even their MI sub with an integrated amp is a lot lighter.

IDK how many cabs were used for the applications I mentioned that benefit from subsonic vibration. I imagine quite a few. I don't think you want heavy subsonic vibration in your house on a regular basis.

I'm not arguing the usefullness, just pointing out examples of cabs rated at lower frequencies.

 

[CoffeeLove]

So, any ideas on cab dimensions? Will be using 5/8" plywood. Should I try to mirror the porting of Eden cabs or stick with the baffles I have to simplify things (2" diameter baffles)?

My apologies if the simplicity of the question is annoying. The more research I do, the more it seems everyone designs cabs different, so I just need to keep it simple.

Thanks

 

[BadExample]

So, any ideas on cab dimensions? Should I try to mirror the porting of Eden cabs or stick with the baffles I have to simplify things (2" diameter baffles)?

My apologies if the simplicity of the question is annoying. The more research I do, the more it seems everyone designs cabs different, so I just need to keep it simple.

Thanks

Without knowing the parameters of those speakers, your best bet is a downsized version of what they came from, as @Downunderwonder said.. .

 

[CoffeeLove]

Without knowing the parameters of those speakers, your best bet is a downsized version of what they came from, as @Downunderwonder said.. .

I thought the same thing at first. If you take a look at the d210xlt, the cab dimensions seem to get bigger with fewer speakers, making me wonder if I should go with slightly more volume.

I could definitely make a 1/4 size version of D410XLT since I actually own one and could take a peak inside for design and dimensions, just minus the horn.