DIY sub performance/value vs commercial subs

[point1]

Hello all,

I am a noob with all of this so please forgive me in advance for any stupid questions.

I was originally looking to purchase the Ed A7-350 for $1050 shipped to Southern California.

Several folks at AVSforum and a couple of guys I have exchanged emails with have encouraged me to investigate the DIY route.

So I came across the post regarding the Infiniti DIY sub and I am interested in doing something like this...

I have forwarded the plans to a cabinet maker to find out what it would take to build two enclosures.

I am also going to take WmAx's recommendation of getting 2 of DIYMA 12" for drivers.

What amp would you guys recommend and what other steps do I need to undertake? such as bracing or fillers?

Finally, would one of these be close to the Ed A7-350 performance?

I was doing some calculation and one would be less than the Ed sub but two would exceed my original budget. I was just curious how it compares to the Ed so I can calculate my effort, time and make the decision between DIY or getting a commercial sub.

On another note, I could potentially get an SVS PB-13 Ultra (waiting on choppin_guy to give me his shipping quote =)

My application is solely for movies and HT

My room size is 21 x 11 x 9

I would prefer to just have one sub because of my limited space but I can probably swing two (specifically the above mentioned plan). I read somewhere that if you have two subs, it is preferable for the subs to be next to the mains. I have floorstanding mains (Energy RC-50s) but I don't have lots of room upfront (I have a projection screen)

 

[Matt34]

Here's my breakdown for two of the Infinity Perfect builds:

2x Infinity SVC $325
1x Behringer EP2500 $350
2x Finished enclosures done by cabinet builder $700

I'm pretty confident two of these will beat the A7-350 in all aspects expect space needed to place them.

One of my unique concerns is the warranty factor and service as I move every 3-4 years it would be nice to have my equipment covered under a warranty in case of damage during a move. They would save me from having to rebuild one.

A used Ultra like Chopin Man's is very appealing and is still a possibility for me also. It really depends on where your priorities lay. Do you want the ultimate performance for your dollar (DIY) or will you be satisfied with a good looking, warranty covered commercial unit that still performs very respectable to just about anything in it's price range.

 

[j_garcia]

I don't really see any commercial sub besting DIY, even from some of the better ID manufacturers.

With two subs they don't need to be close to the mains, they need to be close to each other.

 

[WmAx]

Hello all,

I am a noob with all of this so please forgive me in advance for any stupid questions.

I was originally looking to purchase the Ed A7-350 for $1050 shipped to Southern California.

Several folks at AVSforum and a couple of guys I have exchanged emails with have encouraged me to investigate the DIY route.

So I came across the post regarding the Infiniti DIY sub and I am interested in doing something like this...

I have forwarded the plans to a cabinet maker to find out what it would take to build two enclosures.

I am also going to take WmAx's recommendation of getting 2 of DIYMA 12" for drivers.

What amp would you guys recommend and what other steps do I need to undertake? such as bracing or fillers?

Finally, would one of these be close to the Ed A7-350 performance?

I was doing some calculation and one would be less than the Ed sub but two would exceed my original budget. I was just curious how it compares to the Ed so I can calculate my effort, time and make the decision between DIY or getting a commercial sub.

On another note, I could potentially get an SVS PB-13 Ultra (waiting on choppin_guy to give me his shipping quote =)

My application is solely for movies and HT

My room size is 21 x 11 x 9

I would prefer to just have one sub because of my limited space but I can probably swing two (specifically the above mentioned plan). I read somewhere that if you have two subs, it is preferable for the subs to be next to the mains. I have floorstanding mains (Energy RC-50s) but I don't have lots of room upfront (I have a projection screen)

If you use the DIYMA subs in a slot ported cabinet that I specify, and have it built correctly, it will best SBS-PB13 ULTRA in LF output under 30Hz, and have perfect SQ - absolute transparency (your room acoustics are another matter). I doubt the eD sub even has a small chance of comparing.

Choice of amp depends on budget. The Behringer EP2500 is a good value choice. Great amp. 650x 2 into 4 Ohms. But it has a noisy fan. You have to change out the fan to be silent. Another option, but more costly, is a Yamaha amplifier. The one that outputs 450 watts per channel at 4 Ohms is the P3500S, which costs $500. Ideally, you would use the P7000S, which outputs almost 1kW per channel at 4 Ohms, but this one costs $700. The Yamahas don't have fan noise to contend with.

-Chris

 

[point1]

WmAx,

You are the authority in DIY subs =)

I have a question, I plan on purchasing these drivers on ebay, I am planning on getting two.

Do you have the plans for the enclosure? What do you mean by having it built right?? I am getting a cabinet maker to create the enclosure for me exactly as in that thread. Are their any gotchas that I need to worry about?

 

[WmAx]

WmAx,

You are the authority in DIY subs =)

I have a question, I plan on purchasing these drivers on ebay, I am planning on getting two.

Do you have the plans for the enclosure? What do you mean by having it built right?? I am getting a cabinet maker to create the enclosure for me exactly as in that thread. Are their any gotchas that I need to worry about?

I do not know how consistent the T&S parameters are for the DIYMA subwoofers. The Kappa Perfexts are pretty consistent so it's not really a worry for them. But the DIYMA are a small run speaker designed for special purpose - not a mass produced item from a company that is very consistent. Ideally, you would break them in and test them for the actual parameters before deciding on the final cabinet specifications. The testing device costs $100 - but if this is to be your ultimate subwoofers you really want to make sure you are using accurate parameters to design the cabinet. If you do not want to buy the device, you could alternately ship the subs to me and I will break them in for a couple of hours to loosen the suspension and measure their parameters for you. I can relay them via FedEx to you from that point. I would imagine shipping would be in the $30-$40 range. I will charge a service fee of $20. But for just $40 more dollars you would have the testing device for yourself and be able to test future drivers as well.

You need to have enough bracing to push the panel resonances above the bandwidth that you will use the drivers. You need to use an optimal acoustical dampening material inside the cabinets to absorb unwanted reflections and spurious mechanical noise(s).

-Chris

 

[point1]

Chris,

I can't send PMs yet, can you please PM me your email address? I am very interested in working with you on this.

thanks!

 

[Matt34]

Chris, I know you didn't make the comparison here but when comparing the Ultra to the DIY Infinity Perfects do they match up relatively the same as the DIYMA would? Meaning, will the Ultra will have more SPL above 30hz and the Perfects will perform better below? Also with the 20hz filiter you recommend with the Perfects, how do they compare to the Ultra at 15hz? What kind of output is one looking at with two of these in an average size room? I'm really looking for plenty of clean output down to at least 15hz.

I've gotten some quotes today from cabinet makers and right now I'm leaning towards doing the Infinity build times two.


...and to clarify are you comparing the Ultra to just one Infinity Perfect sub or two?

I was going to PM you this but think your responses would be note worthy here instead.

 

[WmAx]

Chris, I know you didn't make the comparison here but when comparing the Ultra to the DIY Infinity Perfects do they match up relatively the same as the DIYMA would? Meaning, will the Ultra will have more SPL above 30hz and the Perfects will perform better below? Also with the 20hz filiter you recommend with the Perfects, how do they compare to the Ultra at 15hz? What kind of output is one looking at with two of these in an average size room? I'm really looking for plenty of clean output down to at least 15hz.

I've gotten some quotes today from cabinet makers and right now I'm leaning towards doing the Infinity build times two.


...and to clarify are you comparing the Ultra to just one Infinity Perfect sub or two?

I was going to PM you this but think your responses would be note worthy here instead.

I am comparing 1 on 1.

It depends on room volume and placement. Refer to Haloeb's in room measurements. He has considerable extension - about 16-17 Hz in room with the subsonic filters in place.

SPL, in say a 2000 cubic foot room, with the subs corner loaded, can expect to yeild a meausured 120dB - 123db at 20Hz on up, assuming very capable amplifiers are used. 1000WRMS per channel would be ideal.

Avaserfi, with a single unit, could achevei 120dB at 20Hz in a moderate size room, but he was using 2000 watts RMS, and this is pushing your luck with that driver. I would not suggest trying that unless you want to risk destroying the driver. 1000 WRMS is a good range, however.

You can lower response a couple of Hz with a revised cabinet design which I can specify if you wish. However you can not go but so low or the Perfect will run out of it's linear excursion range in demanding peaks.

If you are looking for 120dB at 15Hz, the Perfect drivers are not suited to this task. A pair of the DIYMA drivers could do this in a properly engineered cabinet. But please measure the actual DIYMA drivers before finalizing a cabinet. This is a small run custom driver. Provided TS parameters may not be reliable?

-Chris

 

[point1]

Chris,

I am interested in your thoughts are regarding the DIYMA drivers and the correctly engineered enclosure. I was going to try and switch out the drivers (Infiniti and DIYMA) thinking that I would get the same results but from what you are saying, this might not be the way to go.

I am a total noob here so I apologize for being a pain in the rear. I already have a cabinet maker who has responded with a very reasonable quote for the enclosures. I just want to make sure that the enclosures fit the drivers that I bought.

I am looking at the Yamaha amps as well per your recommendation...

It would be ideal if I can get you (paying you of course) to test out the drivers that I just purchased. Please PM me your email address and contact information if you are interested. I want to do this correctly.

thanks!

 

[WmAx]

Chris,

I am interested in your thoughts are regarding the DIYMA drivers and the correctly engineered enclosure. I was going to try and switch out the drivers (Infiniti and DIYMA) thinking that I would get the same results but from what you are saying, this might not be the way to go.

I am a total noob here so I apologize for being a pain in the rear. I already have a cabinet maker who has responded with a very reasonable quote for the enclosures. I just want to make sure that the enclosures fit the drivers that I bought.

I am looking at the Yamaha amps as well per your recommendation...

It would be ideal if I can get you (paying you of course) to test out the drivers that I just purchased. Please PM me your email address and contact information if you are interested. I want to do this correctly.

thanks!

I have PMed you, per your request.

As far as simply dropping the DIYMA driver in the cabinet intended for the Kappa Perfect --- not a great idea. The cabinet design must be specific to the driver used. If you build the Kappa Perfect cabinets, then you need to just use the Perfects as intended.

-Chris

 

[armstrr]

Here's my breakdown for two of the Infinity Perfect builds:

2x Infinity SVC $325
1x Behringer EP2500 $350
2x Finished enclosures done by cabinet builder $700

QUOTE]

i will be starting my build shortly
2 used 12dvq 167$
ep2500 240 (new)
plywood enclosures 150 including binding posts/feet
oc705 TBD
optional dcx2496 200.

so two subs for $557 or $757 if you want to include the 2496. so these can be done on a budget if you are willing to go the used route.

 

[fredk]

Thats a very good price on the Kappa 12s!