Custom Studio Monitors

[noelburke82]

I am interested in making some Studio monitors with a flat (or as close as) Frequency response.

I am using a HiVI B4N bass-midrange speaker, and a HiVi RT2H-A Isodynamic Tweeter as my choice.

Calculting the Crossover doesn't seem to be too difficult, but calculting the box is, and the amount of information out there is confusing.

Does anyone have any advice on a good starting point?

Also, off topic, who knows of a program which will calculate Crossovers, and boxes?

Cheers.

 

[sreten]

http://www.rjbaudio.com/Audiofiles/FRDtools.html
http://www.geocities.com/woove99/Spkrbldg/DesigningXO.htm

http://www.zaphaudio.com/
http://www.rjbaudio.com/projects.html
http://www.geocities.com/woove99/Spkrbldg/
http://www.troelsgravesen.dk/Diy_Loudspeaker_Projects.htm
http://htguide.com/forum/forumdisplay.php4?f=39
http://www.humblehomemadehifi.com/

Hi,

Speaker design is not as simple as you seem to think it is.
Driver choice is also complex, see Zaphs tests.

/sreten.

 

[Cal Weldon]

Boxes are easy if you know what you like to begin with.

Crossovers are not something you go to a book or table to design. Those are basic starting points only. If you haven't done it, best to consider what Sreten is suggesting.

 

[PeteMcK]

Getting started in Crossover Design

The basics (You've got to understand the rules before you can break them
http://sound.westhost.com/lr-passive.htm
choosing xover point:
http://www.speakerbuilder.net/web_files/Articles/xover article/xpointmain.htm
Baffle Step Compensation: http://sound.westhost.com/bafflestep.htm

Getting it done:
Jay has a page on designing xovers using manufacturers specs without measuring:
http://www.geocities.com/woove99/Spkrbldg/DesigningXO.htm

Calculators:
http://ccs.exl.info/calc_cr.html#second
http://www.sengpielaudio.com/calculator-Lpad.htm
box calculator:
http://www.linearteam.dk/default.aspx?pageid=winisdpro

Measurement freeware:
Synrta - http://libinst.com/SynRTA.htm
ARTA http://www.fesb.hr/~mateljan/arta/download.htm
ARTA Jig - http://zobsky.blogspot.com/2008/01/simple-loudspeaker-measurement-jig-for.html

 

[MaVo]

I dont want to give technical information, as the above is alot. Instead i would like to give a pragmatic advice. If you want speakers and are not in it for the process of designing and building them, use one of the posted zaph (or the other) designs - maybe even if you would like to design your own speakers, its great to have a reference to compare to. Speaker design is more complicated than one would think in the first weeks and months of this hobby. Chances are, that the zaph designs are alot better than anything you would be able to achieve in your first few attempts.

 

[noelburke82]

Thanks guys, that should get me started.

The box part is difficult for me, because I find that it throws a lot of what I know out the window (I've trained in electronics and worked as a live sound tech for several years).

That data that I have available is a lot more advanced than what I have ever seen (Qms, Qts, Qes? No idea what any of this thing means, used to working in SPL's, RMS, Peak, dB, impedance, you know, the basics!).

It's a start!

 

[schmutziger]

My tips

Basta! Loudspeaker simulator
http://www.tolvan.com/basta/

Sirp Loudspeaker analyzer
http://www.tolvan.com/sirp/

Very good tutorials and documentation on the homepages

LspCAD:
http://www.ijdata.com/products.html

 

[noelburke82]

Does anyone actually have an opinion on the two Hivi speakers I mentioned?

(And please, no hard core Audiophiles).

 

[sreten]

Hi,

You seem to have got the cost of the drivers the wrong way round.

Using a tweeter that is as big as 6.5" driver with a 4" bass driver
is bizzare, the B4N http://www.parts-express.com/pdf/297-429g.pdf
is problematic just above 1kHz, with a Vas of just 3L it is too small for
a cabinet that would suit the RT2H-A, bass is somewhat limited.

FWIW I would never use such a tweeter for a monitor, its dispersion
is not typical at all, and that makes it pointless for a quality monitor.

http://www.rjbaudio.com/Microbe SE/microbe SE.html ?

sreten.

 

[Undefinition]

Does anyone actually have an opinion on the two Hivi speakers I mentioned?

(And please, no hard core Audiophiles).

I used the HiVi B4N on a small 2-way monitor for my desktop. Never did a formal write up, but the details are mostly in this thread.
http://techtalk.parts-express.com/showthread.php?t=209059&highlight=buggles

It's a typical metal-cone driver, in that it has a lot of harsh cone breakup that must be notched out in some way or the speaker will sound incredibly sibilant and irritating to listen to. Not a driver I'd recommend for a beginning designer. Some sort of poly cone with a very flat FR.

I haven't use that tweeter, but it's pretty highly regarded. HOwever, your planned design is a very strange match-up. Something like one of HiVi's little dome tweeters would make more sense, especially for budget reasons. With most *small* 2-ways, the woofer is able to cross pretty high (3-4 KHz) without problems, and this leaves lots of options for tweeters.

Not to be cliche, but I highly recommend building a proven design your first time around, if possible. This will guarantee the highest satisfaction with the end product.

 

[noelburke82]

Yes, it was partly due to a cost thing, but I was working on the advice of some of my customers, and noticed that some of the specs crossed over nicely (certain freq's and wattages, and SPL's, again, this is using what I have learned thru live sound, though I admitt that concert sound systems are a different kettle of fish).

I had an Audiophile come in who thought these two would work quite well together, but, different folks different strokes!

I have access to cheap HiVi at my work, so I might consider a different woofer to match my tweeter, as I have heard other good things about this tweeter.

Which woofer would you advise?

 

[Undefinition]

I have access to cheap HiVi at my work, so I might consider a different woofer to match my tweeter, as I have heard other good things about this tweeter.

Which woofer would you advise?

Well, if you're going to stick with HiVi, I'd say go with their F8. That beautifully flat FR means it's going to be pretty easy to work with.

I myself came from the live sound world, and I have to tell you that HiFi speakers are a whole different ball game. Things that matter in live sound (impedance matching, wattage ratings, operating frequency, directivity) are only a tiny part of the picture with HiFi speakers.

In fact, this is all starting to remind me of an event in my life that happened about 10 years ago, long before I got into DIY. A friend and I were attempting to build some studio monitors using some cool-looking drivers and enclosures. The result sounded really pathetic. So I went to the library and checked out a few books on speaker design; I saw tons of graphs and charts and knew I was in way over my head. Sad to say, it scared me away from building speakers for at least 7 or 8 years.