"There should be a diy offering from Nelson Pass soon on passdiy.com."
Well tell him to hurry up dammit! We need new stuff to build
"There should be a diy offering from Nelson Pass soon on passdiy.com."
Well tell him to hurry up dammit! We need new stuff to build
Giskard is absolutely correct about 6 db slopes. They are great in the time domain and can yeild a very coherent sound quality! transient response is amazing! BUT, there can be some drawbacks as well with first order filters! One, this slope isnt suitable for compression drivers and 2402 and 2405 tweeters!
Another thing to understand is that if you use first order filters you tend to have a very narrow sweet spot! You have to be in one precise spot to get the benefits of what these filters sound like. When you stand or sit, move around the whole sonic picture changes! But, if you can live with being in one particular spot to hear the great characteristics of 6db slopes, its worth it! I, personally, for pro use have found 6db slopes to actually sound very good for sub bass!
Now, choosing crossover points for your tweeters, with 6db slopes has to be chosen carefully as you will have a tremendous overlap with your mid driver or woofer! maybe too much!
But, they are excellent if used correctly!
Last edited by scott fitlin; 10-01-2003 at 11:39 AM.
"When you stand or sit"
So you have to be lying down?
THAT'S what I've been doing wrong all these years!
Depends what position your lying down in!
Well, I had the BSS FDS-388 Omnidrive! My system IS considered sound reinforcement!Originally posted by boputnam
This is true, particularly in sound-reinforcement applications, but not in critical listening (i.e., home or studio). Widget watched me go through a reality-check on this a while back.
In spite of ALL the things I could do with this $3800 unit, ie; time alignment, parametric EQ, phase alignment, selectable slopes, etc, the one thing I couldnt deal with was the way it sounded!
Last year I auditioned the FDS-366 24 bit DSP processor. Alot better, but still not as good sounding as analog units like Bryston, Crown, or Urei crossovers!
I also auditioned the XTA DSP unit which is even more expensive than the BSS units, and still it isnt what I desire!
Who knows? maybe in another ten years they will have digital audio perfected! I figured they would have gotten it by now! And that they didnt leaves me wondering!
Hey there are some sweet valvue xovers out there too like Audio Research and Welboune Labs.
Ian
Theres the schematic of the earier Threshold Xover
Maybe i can tell you about my system and the crossover issue i found at last.
I have a 5 way multiamplified system.
It is Hartley 24", Onken W (with 2 Altec 416-8C), Altec 1505/with 2x288, Altec 511/802 and Fostex T925.
I tried many crossovers like the following: Furman, Rane, Luxman 302, Ashley 4 way, dbx 234XL/dbx 120 combo. being the Furman the first used and the dbx combo the last one.
At a certain time i was evaluating the purchase of a digital crossover like the Yamaha D-2040, the Broken Siren Song BSS-388 or Accuphase DF-35.
But, somehow the decision to install a digital device in the audio signal path seemed to be like change all the analogue info into digital and then to analogue. And after the bad CD experience i decided to try something else.
And it is an active-passive crossover, with no power supply, designed for the speaker system with 6 db of attenuation works perfect doesn´t have hums or noise it is very silent and is the best unit i have tried.
Ok i have a Krell KBL preamplifier with a 50 volts maximum output.
For the past years using different crossovers i agree with the KIS principle, if you go digital you will get a digital noise today maybe in the near future that can change.
For time alignement as Dahlquist have done it easier to move the components than to chose a digital or electronic solution.
Hello
I may be getting in late on the crossover disscussion.
My use is for live sound production and I use TDM
analog crossovers the CX24x3 and CX24x2 models.
Excellent sounding units.
The bad news is that the company as been sold so what
happens to them is anyones guess!
The original company was small and ran by Tim D. Miller
"TDM"
They had unlimited lifetime warranty on their products.
I had a problem with one of mine a couple of years ago
and when I called them the man himself answered the phone.
They can be found on e-bay from time to time, also they built
crossovers for Fender, they were the same as the CX series
only with different front panel silk screening and the controls
are red and gray instead of blue and gray. I have seen the Fender
units sell at great prices.
Mike Caldwell
Again, I want to thank you all for this help, and I'm sure others will find it useful information too. Since my original posting I have lined up a Crown VFX2A and a JBL 5235 and some cards. Long term plans will be to follow Ian's lead on DIY tube crossovers and also look into the Marchand, which I have already read about some on line. And I will not leave out searching these forums for the many discussions on crossover tailoring--a suggestion I would emphasize for any new readers who see this.
Thanks, many thanks.
David
We have some developments at diyaudio.com ETA is unknown until the crossover wars subside.
In the mean time I am playing around with some discrete buffers/opamps which are the building blocks of such devices and directly influence the subjective performance.
There are many issues surrounding why active crossovers do/ don't improve performance and the discussions at diy audio cover this well if you are interested.
Ultimately I hope to be able to assist us JBL people with a unit that will exceed the performance of the urie/jbl devices.
Stay tuned
Ian
How are the Crown and JBL working out for you speakerdave?
Originally posted by Ian Mackenzie
There are many issues surrounding why active crossovers do/ don't improve performance and the discussions at diy audio cover this well if you are interested.
Ultimately I hope to be able to assist us JBL people with a unit that will exceed the performance of the urie/jbl devices.
Stay tuned
Ian
Years ago when I used gear that was little better than a Marantz receiver (actually I was using a Marantz 3800 preamp and Marantz 510 amp) inserting any old active crossover improved the sound of the system. As my electronics improved I became less and less an advocate for active x-overs. Many just add their own crud into the system. I await the affordable Pass alternative with bated breath.
Widget,
I agree entirely,
In fact if you can afford the passive crossover designed correctly with no compromise parts, and the physics allow it to work, then in a SOA system an active crossover maybe a sideways step.
That said, an active crossover of the kind we are talking about, which will cater for switchable slopes, Q , FQ and level will allow the JBL nut to experiement of all manner of beloved drivers on the fly.
Thus blending to his/her taste, mood and the number of bottles drunk.
See this link and down load the pdf for details, its quite a read but very impressive.
http://www.passlabs.com/prodlit/xvr1lit.htm
At the moment the Matrix machines are busy negative engineering the design and the Master is impressed by the progress.
The active buffers will be discrete, using Jfets in class A, either minimalist simple followers or a more elaborate cascoded Jfet X super symmetric design, fully balanced outputs of course.
The usual scene is a bulk order of PCB's once everthing is complete.
I will monitor progress and advise accordingly.
Mouth watering isn't it!, Just a cool $21K...don't ask how much it would cost to make....I don't know.
Ian
Last edited by Ian Mackenzie; 12-11-2003 at 02:09 AM.
Now that is one sexy active crossover box hey
Ian
They're so CUTE! the way they just sit and patiently wait for me to build boxes.Originally posted by Giskard
How are the Crown and JBL working out for you speakerdave?
David
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