2-Way | Home Theater | MTM/TMM | Ribbon/Woofer | First build | Advice needed

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Greetings from South Africa!

I've spent the last couple of days researching DIY speakers, and this forum comes up consistently.
I've read quite a few threads here, and it seems like this is the place to be :cool:
I hope you all could provide some insight/advice into my first project.


Background

I'm an avid Home Theater enthusiast and over time have built up a modest 5.1 system at home.
I mostly watch movies, and seldom just sit and listen to music.
Over time, having heard other systems, I've become unhappy with the sound of my speakers, especially the midbass.
Over the last year, I've been looking actively at replacing them, but unfortunately, nothing in the market I've found suits my available size and mounting application, so I've decided to build them myself.


Design goals

  • Accurate and Dynamic sound
  • Sealed Enclosure for "tighter"/more accurate base response
  • Good/high sensitivity - So that one doesn't have to drive them hard for high SPL
  • Flat response
  • Wall Mounted (more on this later)
  • Active Crossovers - Looking at miniDSP 10x10 Hd
  • Will be crossed to my subs at 80 Hz, so must play down to at least 80Hz
  • Probably MTM for the Center, and TMM for the 4 others (more on this later)


Wall Mounted/Room Available

In the home theater, I have a wall mounted projection screen, and no place to mount/stand speakers on the floor/below the projection screen.
Currently my small speakers are mounted very close the the ceiling, all on the same plane.

For the center channel, I have 30cm / 12" worth of height to work with above the projection screen (width and depth is less of an issue here), so I was thinking MTM horizontal would be the best fit.

For the Left, Right and Surrounds, they ware mounted in the corners, and the maximum they stick out horizontally on the walls is 25cm / 10". Length wise (top to bottom) the limitation is around 70cm / 27.5". So in my mind I can stick with the MTM vertical or do TMM vertical.

In both cases I will angle the enclosure towards the listener, downwards.


Driver Selection

I've heard good things about Ribbons/AMT/PMD tweeters, about how accurate they are, how fast they are, and looking at their sensitivity and how low they go, it seems like an excellent fit for what I'm after.

I've been using Parts-Express as my primary site for doing driver research, so the Aurum Cantus G1 Ribbon Tweeter is at the top of list. It goes high, it goes low, it goes everywhere you want. Seems like a good fit?

As for the Woofers, I saw this video from 123Toid, where he mentioned the dynamic nature of the Tang Band W8-2096 8" Underhung Midbass Driver 4 Ohm, and how he sees them as a good fit for Home Theater application.
I'll be able to cross them at around 2000Hz and they go down to 76 Hz in a 0.35 ft.³ enclosure. I was looking at two in series, to bring them to 8 Ohm. Seems like a good fit?


Amplifiers

I'm still undecided on which amplifiers to get, but seeing these units and doing brief research, it also looks like "building" them myself might be the best bang for buck.

it seems like the ICEpower 200ASC Class D Audio Amplifier with Power Supply Module 1 x 200W could be a nice one to buid and power the tweeters
And then the ICEpower 500ASP Class D Audio Amplifier with Power Supply Module 1 x 500W for the woofers.

Any comments/recommendations on this?


Project Concerns

Will DIY speakers be better than Commercial Off The Shelf solutions?
- For the most part I believe that it will be, but I'm going to take a cautious approach here.
- I'll be ordering and constructing one speaker, and testing it thoroughly before ordering the rest.

MTM Speaker Lobing
- Once again a 123Toid video specifies where one needs to put your woofers
- This is a worry for me given this spacing is not possible given my crossover and speaker sizes


In conclusion

Thank you for reading this far :)

I'm hoping that you would bless me with your knowledge and experience, in guiding and commenting on what works and what does not, recommendations, so that I don't make costly mistakes. Shipping to South Africa is expensive :(
 
Hi hard to argue with the G1 especially when you could get the ribbon replacement for them I believe this is harder now due to people using AC ribbons in their home brew drivers . The other classic is the AST25120 slightly less sensitive but still way up there . If you want sensitive drivers to keep up with those 102db ribbons then maybe check out some of the PHL Audio drivers very sensitive and quality, the PHL are not as cheap as that Tang Band . I am sure you will get many other suggestions
 
The other classic is the AST25120 slightly less sensitive but still way up there .

If you want sensitive drivers to keep up with those 102db ribbons then maybe check out some of the PHL Audio drivers very sensitive and quality, the PHL are not as cheap as that Tang Band.

I was actually looking at more sensitive woofers, and wondering how silly it would be of me to not utilize the full sensitivity. Using the AST25120 has the added advantage of crossing lower. So thank you very much for the suggestions/recommendations :)


What is your budget?

It's silly to say this, but I don't really have a budget. I probably just don't want to go over $1000 per speaker, but I'm very flexible.
 
This is the driver I was thinking of PHL 3020 - WAR Audio l Online Store and although not cheap it is an impressive dynamic performer and would massacre the TB . It is worth having a talk to the owner of War Audio he may suggest others . I have heard this used in a couple of active setups and the music making was fabulous. Surprised some of the DIY luminaries haven't chimed in to help in your thread
 
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This is the driver I was thinking of PHL 3020 - WAR Audio l Online Store and although not cheap it is an impressive dynamic performer and would massacre the TB. It is worth having a talk to the owner of War Audio he may suggest others . I have heard this used in a couple of active setups and the music making was fabulous. Surprised some of the DIY luminaries haven't chimed in to help in your thread


Thank you for your continued responses. Those PHL Woofers look really good, especially the Sensitivity. For this specific one you recommended though, I am a bit worried that it seems like they are made more for bass reflex cabinets. Fs being 60 Hz and the Qes at 0.33. But with your "massacre" comment, I will definitely investigate them some more. Just a pity the manufacturer hasn't gotten back to me on an email I sent them a few days ago... Service these days?


I'm also surprised of the lack of responses here, specifically because I'm more worried about cabinet design that driver selection at this stage.

MTM Horizontal vs TMM Vertical. I.e. what should I be looking out for, which mistakes I should avoid, why it's a good idea/bad idea etc.
 
8" and ribbons are kind of a mismatch most of the time. Even if the ribbon can play low enough, they tend to be of higher and lower mass varieties of driver and don't tend to stay effective together. Most 8" woofers of the W8-2096 caliber are geared more toward lower reaching dome tweeters or 3-ways as most of this type will likely not be happy going much above 1.5kHz, let alone 2k due to pistonic behavior at this diameter.

I actually do have a pair of the W8 myself awaiting use with the Peerless DA32TX tweeters. That said- they don't measure as specifications state, and TB underhung drivers are known to differ from public portrayals. Good Xmax, but a highly damped suspension/Qe might not give you the snap you want and be too controlled for your tastes in Home Theater. Dynamics are typically where HT resides, and I cannot say for certain how these will do that task at this time.

For your purposes, and the cost budget you allow, you'll likely have a better result using a biamped plate-amp with DSP for your entry to the DIY scene. You'll have to learn how to measure FR and optimize, but you should be up to the task.

Higher sensitivity drivers require larger boxes. Remember Hoffman's Iron Law- Low Extension, High Sensitivity, and a Small Box- pick 2 and forget the 3rd. Physics will not allow the 3rd to also happen.

Lastly- I see you are wanting a sealed box design, or are heavily biased towards such a decision. Don't let this back you into a corner, as most midbass drivers on the market these days will benefit from a vented box alignment to get the extension you'll likely require- unless you are a an HT fellow that uses the subwoofer for all bass duties. I recommend that you try and get full range as possible in all channels except maybe the surrounds/upper-fronts, as it will open up the HT experience like you have not had prior. Vented boxes are not a bad thing if they are designed appropriately.

Good luck, and ask lots of questions as you proceed...
Wolf
 
Thank you for your continued responses. Those PHL Woofers look really good, especially the Sensitivity. For this specific one you recommended though, I am a bit worried that it seems like they are made more for bass reflex cabinets. Fs being 60 Hz and the Qes at 0.33. But with your "massacre" comment, I will definitely investigate them some more. Just a pity the manufacturer hasn't gotten back to me on an email I sent them a few days ago... Service these days?


I'm also surprised of the lack of responses here, specifically because I'm more worried about cabinet design that driver selection at this stage.

MTM Horizontal vs TMM Vertical. I.e. what should I be looking out for, which mistakes I should avoid, why it's a good idea/bad idea etc.

Pat ar War Audio ship's direct World Wide and is a very skilled loudspeaker designer so don't hesitate to call him he will get your drivers to SA and also help with advice
 
I'd like to point out that I'm not specifically bias towards anything and have a very open mind. My understanding is very limited on speaker design, and is made up mostly from what I've read online. And as you all know, there are tons of nonsense out there, which is why I'm here; to get the practical experiences and suggestions from you all. So thank you very much for all the responses, I really appreciate it!

What's nice about building your own speakers, is that if I don't like how they sound, you can chop and change how they are constructed. Change this cabinet, change/add a driver, change the crossover frequency, etc etc etc. This is very appealing to me!



I like it. The only two shopping ideas I'd suggest is look at what FaitalPro has in the same form factor, and if you are going wiht a plate amp, might as well go full DSP. Use a 2 channel plate amp with built in crossover.

Rather than plate-amping each speaker, I was thinking of re-using the speaker wire I have in place, and amplifying from 2 x 5 channel amplifiers from my AVR's existing location.


8" and ribbons are kind of a mismatch most of the time. Even if the ribbon can play low enough, they tend to be of higher and lower mass varieties of driver and don't tend to stay effective together. Most 8" woofers of the W8-2096 caliber are geared more toward lower reaching dome tweeters or 3-ways as most of this type will likely not be happy going much above 1.5kHz, let alone 2k due to pistonic behavior at this diameter.

It's for this reason why I'm rather looking at the AST25120 as suggested by audiogod66, as it can cross lower, perhaps doing a 1200Hz crossover.
I'm looking at a 2-way design, only from a simplicity point of view, so I'm trying to make this work. Let's call it my compromise on this build :)


For your purposes, and the cost budget you allow, you'll likely have a better result using a biamped plate-amp with DSP for your entry to the DIY scene. You'll have to learn how to measure FR and optimize, but you should be up to the task.

I'm very familier with the MiniDSP and their microphone, as I've used it extensively. This is why I wanted to use the 10x10HD DSP for the active crossover. Any reason that I should definitely be looking at plate amplifiers?


Higher sensitivity drivers require larger boxes. Remember Hoffman's Iron Law- Low Extension, High Sensitivity, and a Small Box- pick 2 and forget the 3rd. Physics will not allow the 3rd to also happen.

I was not aware of his law. Really new on the scene, so thank you from bringing this up. A larger box I can probably live with.


Lastly- I see you are wanting a sealed box design, or are heavily biased towards such a decision. Don't let this back you into a corner, as most midbass drivers on the market these days will benefit from a vented box alignment to get the extension you'll likely require- unless you are a an HT fellow that uses the subwoofer for all bass duties. I recommend that you try and get full range as possible in all channels except maybe the surrounds/upper-fronts, as it will open up the HT experience like you have not had prior. Vented boxes are not a bad thing if they are designed appropriately.

I've read that a sealed enclosure is better from an accuracy perspective, which is the only reason I'm suggesting it for this build.
And in my mind it makes sense, because the phase is inverted when it radiates out the port. And if you create a transmission line, you're delaying it by at least one cycle. From a theoretical purity point of view, this is not desirable.
Practically, does this make a massive difference? I honestly don't know!

I am one of those HT fellows who hands off all low frequencies at 80Hz to his subwoofers, which is why I only need these speakers to go to 80Hz.


Pat ar War Audio ship's direct World Wide and is a very skilled loudspeaker designer so don't hesitate to call him he will get your drivers to SA and also help with advice

Thank you. Shipping to SA is one of my concerns, so will be in contact with him.
 
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