Morning All,
First post in the Forum!
Having already completed a couple of speaker projects.
A Fostex FE127E vented.
and a small LM-1.
Both I use in my lounge for my vinyl through a Marantz PM-48 amp.
Now a good friend of mine has given me a couple of JX 92s, unused still in the boxes. Now these seems to be good drivers from what I have read.
So I am looking to do a project with these full range drivers.
Heres the rub..... being they are more advanced the box design needs to be something a bit more advanced that what i am used to.
My major limiting factor here is size. i do not have space in my flat for a floor standing design.
If i do a smaller box will i need to add a tweeter & crossover? (never done this before!) if so what do i need? do i need any other electronics in the box?
i have done some smaller electronic projects before like headphone amps, so know a bit of this.
Need all of your invaluable help on this!
thanks
Chris
First post in the Forum!
Having already completed a couple of speaker projects.
A Fostex FE127E vented.
and a small LM-1.
Both I use in my lounge for my vinyl through a Marantz PM-48 amp.
Now a good friend of mine has given me a couple of JX 92s, unused still in the boxes. Now these seems to be good drivers from what I have read.
So I am looking to do a project with these full range drivers.
Heres the rub..... being they are more advanced the box design needs to be something a bit more advanced that what i am used to.
My major limiting factor here is size. i do not have space in my flat for a floor standing design.
If i do a smaller box will i need to add a tweeter & crossover? (never done this before!) if so what do i need? do i need any other electronics in the box?
i have done some smaller electronic projects before like headphone amps, so know a bit of this.
Need all of your invaluable help on this!
thanks
Chris
Over the years I have built several Jordan JX92S designs. These include a full range mini-monitor in a 7 to 9 liters enclosure which can be either sealed or vented, a two-way mini-monitor pairing the JX92S with a small ribbon tweeter (Aurum Cantus G2si), and later that two-way evolved into a floor standing mass-loaded transmission line speaker. You will find discussion of all of these on several diyAudio postings if you search.
http://www.diyaudio.com/forums/multi-way/55483-crossing-over-jordan.html
http://www.diyaudio.com/forums/full-range/81634-jordan-ribbon-mltl.html
Several of links in the old postings may be missing but if you are interested, I can help you if you contact me.
Good luck on your project.
Jim
http://www.diyaudio.com/forums/multi-way/55483-crossing-over-jordan.html
http://www.diyaudio.com/forums/full-range/81634-jordan-ribbon-mltl.html
Several of links in the old postings may be missing but if you are interested, I can help you if you contact me.
Good luck on your project.
Jim
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As Jim says, a straightforward vented box is the easiest way to go. The design we used to have on the website had an internal size 30 x 15 x 18 cms and vent size 3cm diameter x 11 cm long.
If you decided you prefer sealed, you can just block the vent and you're close to the ideal sealed loading.
One of the best enclosures was GM's 31 MLTL which was a floor-standing column. Very discrete appearance but sounded terrific. I did work out a bookshelf 'folded' version of that at one stage which I can look out, if you wish. Be warned that I didn't build the folded version, just the standard column.
If you decided you prefer sealed, you can just block the vent and you're close to the ideal sealed loading.
One of the best enclosures was GM's 31 MLTL which was a floor-standing column. Very discrete appearance but sounded terrific. I did work out a bookshelf 'folded' version of that at one stage which I can look out, if you wish. Be warned that I didn't build the folded version, just the standard column.
Hi Jim, Colin
Lots of info there, many thanks.
I am going to stay to a smaller size due to available appartement space so the MLTL is not for me.
Is the difference significant with the addition of the Aurum Cantus G2si? as this is an extra 260USD (i have to search out a euro supplier) on the cost.
Then, with this I will need to build a cross over to add (never done this)....looks like the link is down for this if you can supply would be much appreciated.
For the vented box, will this need to be stuffed/lined....etc
You lost me on the 'folded' version, what does this mean?
Thanks again
Chris
Lots of info there, many thanks.
I am going to stay to a smaller size due to available appartement space so the MLTL is not for me.
Is the difference significant with the addition of the Aurum Cantus G2si? as this is an extra 260USD (i have to search out a euro supplier) on the cost.
Then, with this I will need to build a cross over to add (never done this)....looks like the link is down for this if you can supply would be much appreciated.
For the vented box, will this need to be stuffed/lined....etc
You lost me on the 'folded' version, what does this mean?
Thanks again
Chris
Sreten is right, you have nothing to lose by trying is running full range with no tweeter. You need a baffle step filter though to make it sound balanced. A 1.5 my coil in parallel with a 6 to 8 ohm resistor might be a good starting place, adjust the resistor to taste. If you feel you want more shimmer on top try bypassing the bsc after with a 1 UF cap.
Comments/Answers to Questions
As suggested earlier, you can start with the Jordan as a full range monitor. I use the foam 'egg crate' style absorber to line the insides of my 7 liter vented box. Maintain a clear air flow path between the rear of the driver and the port tube.
If you choose to add the tweeter, the crossover is shown in post #9 of this link:
http://www.diyaudio.com/forums/full-range/81634-jordan-ribbon-mltl.html
Neither the mini-monitor nor the MLTL enclosures that I built were folded so I'm confused by your comment.
As suggested by PJN, you will need a baffle step correction circuit for the full range driver version. The version with the tweeter has BSC built into the crossover network. The mini-monitor and MLTL versions use the same crossover network if the enclosures are 7.5 inches wide as I used.
Your Questions:
"Is the difference significant with the addition of the Aurum Cantus G2si? as this is an extra 260USD (i have to search out a euro supplier) on the cost.
Then, with this I will need to build a cross over to add (never done this)....looks like the link is down for this if you can supply would be much appreciated.
For the vented box, will this need to be stuffed/lined....etc
You lost me on the 'folded' version, what does this mean?"
As suggested earlier, you can start with the Jordan as a full range monitor. I use the foam 'egg crate' style absorber to line the insides of my 7 liter vented box. Maintain a clear air flow path between the rear of the driver and the port tube.
If you choose to add the tweeter, the crossover is shown in post #9 of this link:
http://www.diyaudio.com/forums/full-range/81634-jordan-ribbon-mltl.html
Neither the mini-monitor nor the MLTL enclosures that I built were folded so I'm confused by your comment.
As suggested by PJN, you will need a baffle step correction circuit for the full range driver version. The version with the tweeter has BSC built into the crossover network. The mini-monitor and MLTL versions use the same crossover network if the enclosures are 7.5 inches wide as I used.
Your Questions:
"Is the difference significant with the addition of the Aurum Cantus G2si? as this is an extra 260USD (i have to search out a euro supplier) on the cost.
Then, with this I will need to build a cross over to add (never done this)....looks like the link is down for this if you can supply would be much appreciated.
For the vented box, will this need to be stuffed/lined....etc
You lost me on the 'folded' version, what does this mean?"
My fault - I mentioned that I had sketched an idea for a folded version of Greg's 31" MLTL to make it into a stand-mount speaker. It ended up about 12" deep so not very practical and no guarantee it would work.
If no room for the official column version, I would stick with the 8 litre vented box. Build it to Jim's specifications and his original designed included a BSC circuit to balance the sound which works fine.
If no room for the official column version, I would stick with the 8 litre vented box. Build it to Jim's specifications and his original designed included a BSC circuit to balance the sound which works fine.
hey there.
for the inductor is there a specific resistance i should be looking for.
Sourcing in France, so found this:
Inductance Bourns SDR1005-152KL CMS 1.5 mH 6.3 ? 1 pc(s) - Vente Inductance Bourns SDR1005-152KL CMS 1.5 mH 6.3 ? 1 pc(s) sur conrad.fr | 1056169
have pretty much everything else ready to go, though after 21 faithful years lost my Marantz the other day.....
Hello All,
Finally after months of planning and moving forward bit by bit i am done!
Easy build up until the finitions.... i couldn't decide what to do so this took me a while think over how to proceed.
Then i lost my marantz amp after 21 years of faithful service
& our neighbours daughter decided to pierce one of my fostex drivers with a pen....
So with the pressure on i opted for an easy fix of a decorative PVC film.. it looks...ok and will have to do until i can decide for a definitive decor.
Thansk to all for your help and advice!
Finally after months of planning and moving forward bit by bit i am done!
Easy build up until the finitions.... i couldn't decide what to do so this took me a while think over how to proceed.
Then i lost my marantz amp after 21 years of faithful service
& our neighbours daughter decided to pierce one of my fostex drivers with a pen....
So with the pressure on i opted for an easy fix of a decorative PVC film.. it looks...ok and will have to do until i can decide for a definitive decor.
Thansk to all for your help and advice!
Attachments
GM
Too early to tell so far. they were new out of the box and have had only 10 hours running in time.....
Also as i changed the amp too, so i have no reference points.
That being said the clarity from an Elliot Smith vinyl album is better than previously, but is it the speakers? the amp? or both??
Thinking that i should've added a reflex.... but lets see.
You may find that the higher frequencies will sound better if you tilt the speaker up toward your ears when you are in the listening position. Again this depends upon on where you listen within the room and if you have a favorite place for your music listening. Experimenting with placement will enable you to improve your sound.
If you add a port to your box, you would improve the response for the lowest frequencies (lowest 3 dB down point would move about 30 Hz lower versus a sealed box). What is the internal volume of your enclosure? Perhaps I could make some suggestions.
If you add a port to your box, you would improve the response for the lowest frequencies (lowest 3 dB down point would move about 30 Hz lower versus a sealed box). What is the internal volume of your enclosure? Perhaps I could make some suggestions.
Definitely try this. Remove those records next to both boxes so you can experiment with different amount of toe in as well. And put some grilles on there if you have little ones running around with pointy objects
GM
Good to see you on here GM
The JX92S sounds best when listened off-axis, with the two driver axes crossing in front of the listening position. That way the stereo image is stable as you move left-right of the centre listening position.
Having said that, firing straight ahead will sound OK but the stereo imagery will be less than its best.
Hi Jim,
I did want to add the port originally but the length that was recommended by Colin (hey!) was 3cm diameter x 11 cm long for internal dimentions of 30 x 15 x 18 cm. Unfortunatly i could not find anything to these dimens so i went with a sealed box.
If you have an idea that would be greaat!
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