Heh-heh-heh. Now there is a sucker question if I ever saw one!!! 😉
Pretty darn good - providing you like Omni type speakers! YMMV. I only had about a $400 budget to work with - and for that amount of $$$ it would be hard to beat 'em. The AMT1's make for a sweet top end but you need to be a fan of dipole / bipole type of ribbon speakers and some people just don't seek that path of reproduction (some go for horns - domes - etc.)
My personal test for speakers - after all of the basic things - is can I listen to them for hours and not feel fatigued or find things boring - and these speakers pass that test with ease. So these are my benchmarks to work from for now. I would love to try a couple of OB's and Econowave types but the budget won't allow that just now - so I have some time to dream and scheme.
The rest of the music chain needs work too. I'm currently hooked up to a HK AVR-354 and while it is decent for audio and great for HT it needs an upgrade for serious audio. Then there is the battle for source material and I want to go music server for that - buuuuuuuut - blah - blah - blah. Let's just say that I have a lot of projects to play with in the future and in the mean time I'll kick back and enjoy what's on hand. 😉
Send me a PM and maybe we can get hooked up - I'm over in Smyrna - not to far away from "Music City".
I had the pleasure of hearing the radial speakers at decfest
The decware radials were my second fav
Next to the corner horns. So I'm a fan!!
As far as projects go I have a ton too get right.
Lucky for me it's the slow season.
The decware radials were my second fav
Next to the corner horns. So I'm a fan!!
As far as projects go I have a ton too get right.
Lucky for me it's the slow season.
Oh man - that's backasswards from getting over to here. Probably around 45 to 60 min. each way - and that does not account for getting through "Music City" without hitting traffic or tavern delays. 😀
This is a concern only if you use a single stereo power amp to drive the speakers.
I am with first order crossover for my midrange and the recomended from MJK low pass crossover for the Goldwood (13mh, 150mf) and at higher volume levels I get too much midrange cone excursion 😉
And this is due to two reasons, the first is that the big woofer makes allot of back current and the amp that I use now has damping factor under 30... so that current manages to pass through the 60/70 mf capacitor in series with the midrange 😉 and because in first order there is no parallel inductance to deal with it, it moves the membrane of the midrange...
The second reason is that I designed my own OB using the EDGE program and it is much smaller than the original MJK baffle... due to that the raise in SPL for it is centered around 900-1100 hz and the fall (baffle step) is around 200-250 hz
So with first order crossover at around 200-250 hz I get a second order (12 db/oct) cut off slope, but I get the bass driver inducing midrange cone movement as well... 😉
The aim with the smaller OB was to achieve 100% accurate SPL EDGE prediction as it is with 4 open ends (or edges) suspended in the air and the sound is very good, but that comes at a price... 😉
With higher damping factor amplifier I am able to go to higher volumes before the midrange membrane begins to move too much... but again at some point the effect is present...
I tried to run the low frequency part and the mid/high frequency part separately and both run smooth and without distortion almost to the maximum power 😉
And if I go for a second order electrical crossover I will get a third order overal slope - e.g. 18 db/oct... so I'm kinda stuck 😕
But if you go for first order slope with the original OB dimensions and driver position, then you'll get a rise in the SPL somewhere between 150 and 400 hz which will be unpleasant for sure!
Have in mind that while the original MJK low pass crossover is aimed at 100 hz electrically, the actual overall (the sum of acoustical and electrical) crossover is 200 hz for the H-frame 😉 because of the rising response of the Goldwood and the length of the path of the sound waves around the H-frame...
So you have to play with the EDGE program, a pen and a piece of paper in order to design an open baffle and the respective BSC and etc with smooth frequency response...
For instance a first order crossover and smaller OB size leads to such complicated circuit:
Note that this is the crossover for an fullrange or a midrange which falls in response with no spikes and peaks in the end of it's response!
Here is the ob for which this crossover was created: http://www.diyaudio.com/forums/full-range/131590-mjk-s-jordan-jx92s-ob-goldwood-gw-1858-woofer-h-frame-51.html#post2197163
On the back you can see the bigger OB which it replaced... Note that the bigger the OB the more the bass is!
And here is some evolution of the system: http://www.diyaudio.com/forums/full-range/131590-mjk-s-jordan-jx92s-ob-goldwood-gw-1858-woofer-h-frame-55.html#post2365991
That's written by Me being a good external correspondence student of MJK 😀 (at least I hope so)
Attachments
Alright, then all written applies except for the danger of excessive mid/full range cone movement which still applies actually... 😉
Best regards!
Best regards!
Talked to Marchand today about crossing over and got that tucked away
My new plan is to find a baffle that looks nice.
Any thoughts?
My new plan is to find a baffle that looks nice.
Any thoughts?
Yes: Quarter Wavelength Loudspeaker Design Gallery
And apart from the ideas you'll get from MJK's gallery, you could consider using cork and leather 😉
And apart from the ideas you'll get from MJK's gallery, you could consider using cork and leather 😉
Is the Marchand crossover going to provide enough flexibility? Depending on the baffle you design, you will definitely need to optimize the crossover frequencies, slopes, and the amount of low frequency boost. The final tweaking will be by ear and might require very subtle adjustments to the crossover values. In the extreme case the baffle, crossover, and H frame may never work well together. Unless you do the calculations up front you are entering into a trial and error design approach. The effort you put into designing the system before cutting any wood will be reflected in the sound quality you eventually produce.
If I use the Hframe with the 126
The crossover would be set to 100hz on the low and 400hz
All second order right?
The crossover would be set to 100hz on the low and 400hz
All second order right?
Beside the right slope and frequencies, it looks like the alignment of the crossover is important here. It is Linkwitz-Riley (Q=0.5) rather than Butterworth (Q=0.707).
Yes.
Low pass is 2nd order LR at 200 Hz with 7 dB of boost.
High pass is 2nd order LR at 400 Hz.
This is what sounds good to me in my room with my equipment. You could start with those setting and then dial the crossover around the values to get it sounding right in your room with your equipment.
Martin,
Just one question. When you say "7 db boost" does it mean that the low-pass amplifier is just providing 7 db more gain (in relation to hi-pass amp), or there's something else? I've seen cases where an additional 1st order low-pass at 20 Hz was added to a second order low-pass (at 200 Hz for example) , to provide a compensation for baffle-loss...
Thanks
Vix
Just one question. When you say "7 db boost" does it mean that the low-pass amplifier is just providing 7 db more gain (in relation to hi-pass amp), or there's something else? I've seen cases where an additional 1st order low-pass at 20 Hz was added to a second order low-pass (at 200 Hz for example) , to provide a compensation for baffle-loss...
Thanks
Vix
I find the dBx Driverack PA to be very easy to use. I am sure the Behringer DCX2496 is also easy to use, it has a computer interface using a USB style of cable. Both crossovers use XLR cables which my pre amp and amp both support, this makes reconfiguring the set-up easy.
I have a new OB configuration in my room and last night I was experimenting with the crossover settings. I had simulated two options that both looked good. So I set the dBx to have one option as number 8 on the menu and the second option as number 9 on the menu. I could switch between both options in real time and decided which I liked better. Then I could tweak the specific settings to dial it in even more. Quick, easy, and powerful.
I'm curious about the new OB of Martin 🙄 Because recently I found that Eminence Alpha-15A is available locally at a pretty decent price... and my hands began itching... allot... 
But I can wait a little for a new OB design... instead of trying 2 x Eminence and a Fostex per side....
But I can wait a little for a new OB design... instead of trying 2 x Eminence and a Fostex per side....
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