Comments on DIY 5.1 system? (1 Viewer)

[Daniel J Hauer]

Hello all!

First off, this is my first post and I'm excited to be delving into the world of HT. I am certainly not new to audio or electronics, but this is my first attempt at a HT system.

Due to school I will not get to building anything until next summer, I am trying to get some plans started.

Bear in mind that I do not have a huge budget for this venture.

The plans for all the speakers are basically the same. I am thinking of a D'Appolito 3/2 speaker geometry using Tang Band W4-657S mids. I have not fully decided of the tweeters yet, but I have found some sheilded soft dome tweeters on sale.

The specs are as follows:

Fs 1473Hz
Qms 1.54
Qes 2.00
Qts 0.87

The specs for the Tang Bands can be found on their website and the tweeters are on sale at Apex Jr. (I would provide direct links, but that seems prohibited.)

I plan to go ported and WinISD shows a good response with an internal volume of .4 cu ft utilizing a single rear-facing port 2.5" x 5" for a 69hz tuning frequency.

The system will be crossed over at 3khz (perhaps a bit higher) and my calculations show that a 4.5" driver spacing would be appropriate which seems to work out nicely.

I will have a subwoofer(s) in the system and have about 1950W @ 4 ohms for bass duty. I am undecided on the subs and plan on talking with Dan Wiggins about that issue.

The speakers will reside on steel speaker stands filled with sand. My planned reciever is a Denon 6.1 unit. (for upgradability)

Any opinions on the driver / enclosure selection or any other aspect of my ideas would be greatly appreciated.

Of course, expect many more questions as this project evolves.

Thanks for the help!

D Hauer

 

[ThomasW]

What's the point of using such tiny drivers?

 

[Daniel J Hauer]

I guess that's why I'm posting my ideas on this forum.

I've heard good things about the TB's and these particular drivers model well in an enclosure size that I'm looking for (~.5 cy ft).

Would you suggest stepping up to 5" or 6.5" speakers?

 

[Brett DiMichele]

Daniel,

check this link out...

http://forum.stryke.com/viewtopic.php?t=134

They may or may not be what you are looking for but it's
similar to your own idea and the drivers are very high quality.

I have dealt with John numerous times and he offers great
products, great value and quality is standard fare.

There are also kits from Rutledge Audio Design (Micro's),
Adire Audio and GR Research to name a few others..

All worth looking into!

 

[Daniel J Hauer]

Thanks for the link, Brett.

Is there any particular reason you would suggest going with a kit as opposed to designing my own cabinets?

Also, what drivers would you recommend for this system? Bear in mind I'll be needing 10 mids and money is an issue.

Thanks.

 

[Dan Hine]

Is there any particular reason you would suggest going with a kit as opposed to designing my own cabinets?

Because designing speakers isn't easy. Without test equipment, knowledge and a lot of patience you'll probably not be too happy with what you come up with. Maybe you have all those things and it would be worth it to you, but a kit is a much safer bet.

 

[Hank Frankenberg]

Daniel, designing speakers that sound very good is a very difficult task. Go with kits designed by people with experience. I'm not discouraging you from learning, but if you build kits, you can study their crossovers and read design books at the same time to gaine some insight and understanding. Lots of people recommend Vance Dickason's "Loudspeaker Design Cookbook", but I recommend buying the two Radio Shack books on speaker design first. I think the first is "Loudspeaker Design", but could be wrong. The second is "Advanced Loudspeaker Design". Then, if you're still interested, buy the Cookbook.

Some of the TB drivers are good for very small cabinet requirements and low cost, and doing a ported cabinet with a TB 4" full range driver will whup up on a Bose cube. If you're not size-constrained, go with larger, better quality drivers for your L,R and C speakers.

 

[Daniel J Hauer]

Thanks for your concerns, but I'm not exactly new to speaker design. Ironically, I have had all three books that were mentioned for probably 5 years now.

I have been designing and building car audio systems for about 3 years now. These are SQ systems, mind you one of which was sponsored by Xtant and seen at SEMA this year.

As for equipment, I have alot of my own and plenty more available as I am a EE major.

Now, I would like to design a 5.1 system utilizing a D'Appolito setup that is taylored for my needs. i.e. within a reasonable budget (I am a college student) and relatively small (~.4-.7 cu ft a piece.) With the MTM setup, I am trying to achieve better power handling and a symetrical radiation pattern.

So, does anybody have any better suggestions as to what drivers I caould use?

Thank you.

 

[Andrew Steel]

If you are an EE take a look at Siegfried Linkwitz's ( called linkwitzlab )page it will suit your way of thinking and it explains a lot

Small drivers are better for transient response (all else being equal) but less capable of low frequency reproduction - as always the task is to find best compromise.

Andrew

 

[Brett DiMichele]

Daniel,

I mentioned the Stryke kits primarily because they are a
tremendous value if you pre order them now you can get all
of the drivers and raw cabinets very affordably. The other
reason is because they use Seas (read: Very good drivers)
plus they are Coaxial which gives you perfect time alignment.

They should sound great and they will be relatively small
in size.

But there are so many choices out there.. So take your time
and look around.

But like everyone else said.. Designing from scratch is
very hard.. The enclosure isn't even the hard part... The
Crossover *IS* without tons of measuring equipment and an
Anechoic room it's hard to get accurate readings unless you
are very skilled at it.

 

[Daniel J Hauer]

I must say that after a registration process that was nothing short of hassling and only posting in one thread here, I am quite dissappointed.

I would not be posting in the DIY section if I did not want to DO IT MYSELF.

After reading Patrick Sun's thread on keeping projects to one thread, I will do just that. Now, if we are done judging whether or not it is a good idea to design a system from scratch, I still would like suggestions on drivers to use for this project.

Thank you.

 

[Mark Krawiec]

Here are my thoughts.

First, you seem annoyed that folks are steering you towards a kit and you want to do it yourself. Point noted.

Drivers-the Tagbands are reasonably nice, and will impress if your reference is bose or any similar size/consumer grade system. Nonetheless, in this price range, there isn't much to consider.The vifa TC series is reasonable. Some of the budget audax come to mind as well.

4-4.5" drivers certainly will give a small design, but you will be limiting your spl notably. Look at my design here with the vifa TC11. It's not what you want exactly, but it is a design based on a woofer of roughly the same swept volume. Note also my comments on max spl. Your max will be 6 dB more. Still very limited. Lots of excursion related distortion-it's very easy to overdrive a unit this size. As an EE I'm sure you can see why small drivers are, in general, a poor choice for HT in all but the smallest rooms. So, unless your heart is geniunely set on a unit this size, consider 5.25. Notably more swept volume and more selection. Consider, for instance, the GR M130. Very inexpensive and generally well regarded. Still won't get reference levels, but much better.

I would recommend following. Do a google search for the "FRD consortium" and download unibox, something called the BDS, and maybe ARPE. Use these to model a box and look at diffraction and lobing effects. Since you have plenty of access to test gear, use some form of broadband impulse equipment to generate actual FR and phase. Input that into your modeling software of choice. This is a little less common at a typical university, but you might still find someone. Then, build your crossovers and test your result.

Fwiw, I'm trying to finish my own HT speaker setup based on usher drivers (ya, ya, the Scan Speak clones-but very, very good ones!) using a 7" and 1" in a standard sealed MT format. Look here. With these I get a fairly small box of 12x7.5xI forgot and a modeled spl of ~102dB for one unit at max excursion, half space. Not quite reference, but close. Plus, an F3 of ~60. I started out looking at smaller drivers because size is important, but ended up with bigger ones because, well, the sound is too.:wink:

 

[John E Janowitz]

Daniel,

if you're looking for a good combination of inexpensive drivers, you may be interested in the ones I am using for the system after I finish the Center Point series.

I am using the 6.5" Silver Flute wool cone drivers that Madisound has. There is also a 5.25" version. Non-shielded is $14.25, shielded if $15.95. Drivers made by Silver Flute are of amazing quality. I pulled a 5.25" sample apart and found all kinds of good stuff in there. It had a nicely extended T-pole, cross drilling in the VC former for better cooling, venting in the basket under the spider, etc. These wool cone drivers I would say are easily a comparison to drivers like the Vifa P17, the Seas P17REX, etc that sell for up in the $50 range.

http://www.madisound.com/silverflute.html

I'm going shielded for all of my kits now. That way I can keep all 3 fronts identical. The shielded tweeter was hard to fidn to match with those mids. I ended up going with the Seas 27TDFC/TV. It is shielded and uses the shielding cup as a rear chamber. Fs of 800hz. It is very close to the Seas 27TFFC that I still feel is the best low cost tweeter out there. I plan to Xover the system somewhere between 1600hz and 2000hz, depending on what the power response looks at when I get to that point. These tweeters are only $26.85 each.

http://www.madisound.com/seas/H1210.pdf

If you don't need a shielded tweeter, the Seas 27TFFC does sound a little better and has lower FS making it more versatile.

Also, what kind of measurement system and Xover modeling software do you have? I use Praxis and LSPCad. If you use either of those I could send you some data to look at.

Regarding the warnings of others, don't be too harsh on them. Designing Xovers IS a lot of work. Taking manufacturer data and designing the xover based on that is nearly useless. If both drivers had perfectly flat impedance curves and originated at the same point in space it woudl be easy. Textbook values would apply, and phase would be aligned properly. As soon as you put 2 drivers in a box though, you not only need to get response flat but align phase properly.

A few tips on Xover design. First, get your impedance flat. Then all the other xover components will do more what they are supposed to do. Offset your tweeters with a 1.4 ratio and round your edges. This will smooth your diffraction and give you varriances of only .25dB or so. Centering a tweeter can give you much bigger ripples.

For anyone who is designing their first kit, the Seas coax drivers are a good starting point. Being time aligned, it helps a lot in getting your phase correct.

John

 

[Brett DiMichele]

Daniel,

Remember that you catch more flies with sugar than you do
with vinegar.

I understand that you consider yourself "experianced" I
would never make that claim about myself. Not on this forum
with people like John Janowitz, Thomas W, John Marsh, Pat
Sun, Jack Guilvey(sp?), Brian Bunge... In other words the
guys that DO know what they are doing!

I only made a recomendation to try and help.. Sorry that
you got so annoyed with us for trying..

Since I am not skilled enough to build my own speakers from
absolute scratch (that would be a horrendous failure) I can
offer nothing further. Good Luck whatever route you choose.

 

[Brian Tatnall]

Daniel,

Do you have a specific price range you are looking at? (I know you said not a lot, but there are a lot of use here and we come with different ideas of 'not much')
That would help narrow things down.

Which denon or how much power?

What are your musical preferences? Do you like aggressive highs or mellow highs? Neutral and clear?

I'd suggest the Audax TM025F1 as a tweeter it is astounding for it's price IMO.

If I can make a contribute I suggest looking at the
DIY Loudspeaker Designer's Selection Guide

They list tons and tons of drivers giving you exactly what you are looking for (opinions). Very helpful.

http://ldsg.snippets.org/index.php3
click on the index button and away you go

I'd take a look at the parts express Dayton drivers along with vifa and peerless.

Tangband is alright, but you might be able to get more for your money.

bunch of decent drivers that can be used for kits
http://www.adireaudio.com/diy_audio/drivers/drivers.htm
http://www.gr-research.com/drivers.htm
http://www.stryke.com/drivers.html

major US distributors speaker and x-over
http://www.madisound.com/
http://www.zalytron.com/
Link Removed
http://www.partsexpress.com/

Might take a look at the tweeters the above distribtors are using in their DIY stuff.

If your trying to stay real cheap with the tweeter I suggest narrowing it down to three cheap ones that you think might please you and then order one of each. That way you can decided which you like best and order the rest instead of ordering them all at once and being unhappy.

My .02 welcome to the board and good luck.

 

[Brian Tatnall]

Hey just looked at your profile and noticed your gveto from Sound Illusions right?

This is mustatang

Your in Peoria, IL and I'm pretty darn close in Wheaton. After January I should have some adire kits done with the Audax tweet if you wanted a listen.

Glad to see you here.

Wow, never noticed how close the new thread and reply buttons are...almost had a new thread with this post.

 

[Daniel J Hauer]

Hi Brian.

Yes this is Gveto from SIN. Actually Gveto from CAF where I have like 1k+ posts. I really don't like this policy of using names as SN's primarily because I hate to be call Daniel (or Dan). Ironically, everyone I know calls me Gveto.

As far as a budget goes, I'd like to keep the cost of the drivers under $500. This is for all 5 speakers with (unless someone changes my mind) MTM arrangements.

I'll check out that selection guide you linked too. Sounds like a useful resource. As far as distributors, I've ordered from Madisound many times and have been very happy. Also anything I can purchase through PE would be great since I am an authorized dealer through them and can get the products for cheap.

As far my goals for the sound, I can only tell you what I like in my car since that has been my primary area of interest. I'm using Peerless 6.5's in big sealed doorpods that produce great midbass. For tweets I'm using some Vifa softdome MG series tweeters slightly off axis (due to install options). So, I guess I'm looking for a more natural, neutral sound with punchy midbass. Of course that is a good reason not to use 4" drivers.

As for the receiver, I really don't know which one. I saw a post in the receivers area about a HK unit for $199, but that looks a bit shady. It only puts out 50W per channel. Most likely if I buy a new unit from UE or the such, it'll have a bit more power like 65-75W per channel. Of course I'll keep my options open for using external amps.

Thanks for the constructive help! I appreciate someone helping me do this instead of telling me it can't be done. And, I would be interested in hearing your setup to get an idea of what I want to do. As much as I like Adire, their DIY drivers don't seem like a good deal. Perhaps I'm wrong though. It's happened before.

 

[Daniel J Hauer]

John E Janowitz:

Thanks for your post. I've been looking at Stryke Audio and like the S1 series for an application such as mine.

Couple question, though. Do you suggest that everything be flush mounted on a cabinet? I see that the S1 cabinets are all countersunk. Also, could you explain the 4.1 ratio you mention for tweeter placement? I was planning to make the distance between the woofers and tweeter one wavelength of the crossover frequency for proper radiation patterns. How does this figure when you offset the tweeter? Is the distance still measured from the center of the cones, or from the vertical placement of the tweeter to the center of the woofers?

Also, I've been looking at your crossover designs for your kits as well. I see that the tweeters utilize a third-order filter with an attenuation network. But, what .33mH and 12ohm resistor in series do? Also, would you suggest the addition of a series notch filter or impedance compensation network to help flatten the impedance?

Thanks for your help.

Edit: I just read the section on S1 page about the resistor and inductor purpose. Would this be something that is designed into the corssover from the start, or is it added with different values to acheive the best sound?

 

[Mark Krawiec]

I forgot about those sliver flutes till John mentioned them. They would also be an excellent choice-a bargain at their price. I haven't worked with them, but there are alot of impressed folks over on the MAD board using these.

mark

 

[Robert_CA]

Brian,
I live about 1/2 hour East of Daniel. I might be interested in coming up to listen to your 281's when you complete them in January if that's OK with you. I've already built an Adire Tempest sub and had just completed my LCC. The next project for me is to do the Adire mains although I'm waiting for word from Adire on the roll out of the two proposed 3 way variants of the 281's(I sure hope that it's soon!). I'm an ex-Chicagoan myself who went to Illinois State. I'd love to bring my LCC up to see how it integrates with your mains. What are you using as your center channel right now?