smithie said:
Smithie,
Could you put line level BSC between the pre-amp and power amps?
then you are not losing precious watts - you say you don't turn the volume past 10 o'clock.
I found the JX92 unacceptably bright without it.
Andy
Hi smithie
My listening room is not much bigger than yours and I never managed to get proper sound with a traditional setup with speakers well away from the walls.
Why not use the room to your advantage and build a pair of closed boxes, volume 12-15 liters with a Q around 0,5-0,6 and place the speaker closest possible to the floor/sidewall/backwall.
In doing so you get max room gain at low freq. and your speaker is at max distance to all other reflecting surfaces in the room, so you minimize early reflections to the benefit of soundstage...
Maybe you can place sound absorbent material on the floor and walls in close proximity to the speaker.
That`s what I intend to do when time permits (next year)
cheers
JB
My listening room is not much bigger than yours and I never managed to get proper sound with a traditional setup with speakers well away from the walls.
Why not use the room to your advantage and build a pair of closed boxes, volume 12-15 liters with a Q around 0,5-0,6 and place the speaker closest possible to the floor/sidewall/backwall.
In doing so you get max room gain at low freq. and your speaker is at max distance to all other reflecting surfaces in the room, so you minimize early reflections to the benefit of soundstage...
Maybe you can place sound absorbent material on the floor and walls in close proximity to the speaker.
That`s what I intend to do when time permits (next year)
cheers
JB
hi
never thought of the bsc between the pre and power,if i get hold of the parts i might try that although ive never found the jx92s that bright in any of the desins ive tried,other then what a lack of bass can make it sound like,i guess thats the subjective nature of hifi sound quality that varies between person to person!
i think bad,i guess you can tell from my previous post that im leaning towards the idea your mentioning!
why do you say 12,15 ltrs,sorry for my ignorance im not very scientific,understand the specs etc,wouldnt that be to big for this driver,only saying that as teds site seems to recomend 8ltrs for this type of enclosure?
if,when i go this route i was going to build them as tirangles so they fit tight into each corner and also give me the 30 degree angle needed for this driver and use as wide a baffle as possible to join the walls together(yeah proberly look very weird...but i can handle weird!)...any views,rough frq plots etc, if i go this approach,at the moment im still trying to get the vtls to my liking,as ive said ill give it this weekend as they took so long to make i feel i have to give them a fair crack of the whip(plus its cold and wet outside,so not in any rush for building a new smithie enclosurer!
smithie
never thought of the bsc between the pre and power,if i get hold of the parts i might try that although ive never found the jx92s that bright in any of the desins ive tried,other then what a lack of bass can make it sound like,i guess thats the subjective nature of hifi sound quality that varies between person to person!
i think bad,i guess you can tell from my previous post that im leaning towards the idea your mentioning!
why do you say 12,15 ltrs,sorry for my ignorance im not very scientific,understand the specs etc,wouldnt that be to big for this driver,only saying that as teds site seems to recomend 8ltrs for this type of enclosure?
if,when i go this route i was going to build them as tirangles so they fit tight into each corner and also give me the 30 degree angle needed for this driver and use as wide a baffle as possible to join the walls together(yeah proberly look very weird...but i can handle weird!)...any views,rough frq plots etc, if i go this approach,at the moment im still trying to get the vtls to my liking,as ive said ill give it this weekend as they took so long to make i feel i have to give them a fair crack of the whip(plus its cold and wet outside,so not in any rush for building a new smithie enclosurer!
smithie
smithie
Well, 15 liters may be a little optimistic, 12 seems to be suitable.
Ted recommend 8 liters so you get maximum flat freq. response with a Q around 0,7 which is good in most installments.
What you and I need is a freq. response down as low as possible without overshot and without BSC.
I remember once I built a ribbonspeaker outside at wintertime -20C and heavy snow, but what the hell...I just HAD to test a new idea.
JB 😀
Well, 15 liters may be a little optimistic, 12 seems to be suitable.
Ted recommend 8 liters so you get maximum flat freq. response with a Q around 0,7 which is good in most installments.
What you and I need is a freq. response down as low as possible without overshot and without BSC.
I remember once I built a ribbonspeaker outside at wintertime -20C and heavy snow, but what the hell...I just HAD to test a new idea.
JB 😀
hi thinkbad
i know where your coming from about the idea thing and the need to do it there and then,nowhere like the weather conditions youve stated mind you,my worse case was pouring with rain so decided to build my mdf speakers in the house,kitchen...NEVER AGAIN....the mess,dust,it got everywhere and not just in the kitchen,it has a knack of sticking to you,floating to every part of the house...so ive banned myself from doing that sort of thing again!
ive run 8ltr sealed enclosures before with these drivers and quite enjoyed there music making,what was more impressive was the enclosures was made from pine,just slapped together so you can say the enclosure was certainly adding its own sound,yet they still had better magic to the sound compared to these vtls ive built,as someone else said,better to have limited,quality bass,then loads of bad bass...amen!
i know theres programs out there that could proberly plot the frq respones etc,but i havent got any idea how to use it if i had it...hence i just build it and see..
what set up have you got?
are you using valves/tubes with yours?
smithie
i know where your coming from about the idea thing and the need to do it there and then,nowhere like the weather conditions youve stated mind you,my worse case was pouring with rain so decided to build my mdf speakers in the house,kitchen...NEVER AGAIN....the mess,dust,it got everywhere and not just in the kitchen,it has a knack of sticking to you,floating to every part of the house...so ive banned myself from doing that sort of thing again!
ive run 8ltr sealed enclosures before with these drivers and quite enjoyed there music making,what was more impressive was the enclosures was made from pine,just slapped together so you can say the enclosure was certainly adding its own sound,yet they still had better magic to the sound compared to these vtls ive built,as someone else said,better to have limited,quality bass,then loads of bad bass...amen!
i know theres programs out there that could proberly plot the frq respones etc,but i havent got any idea how to use it if i had it...hence i just build it and see..
what set up have you got?
are you using valves/tubes with yours?
smithie
smithie said:
It may be that your amps are somewhat low on damping factor (highish output impedence, higher system Q). Your comments on the driver may also reflect a relatively high Qt (I haven't checked). That combination would give boomy bass in a box designed for a lower Q driver. What matters in the end is the total system Q. Many paths to get there are possible. It would make sense to use an enclosure, which combined with the driver, gives a Q on the lower end, e.g., 0.6 or so (more highly damped). For a real low Q enclosure you could cheaply experiment with a the non-enclosure - open baffle. Your bass ain't gonna be boomin with that.
Sheldon
hi
thanks for your input,ill have to try and find out my amps specs,damping etc,not easy as there chnese so info is next to non-existant( ming-da finest).
funny enough i did try a open baffle,cant rember the baffle size as it was a while,i had the driver low down and the baffle slightly tilted back, i thought they was ok (certainly no bass boom) but felt that the sound had dips and peaks to it,no surprise really as there was no science to my experiment!
i so wanted to go this route as its one of the reasons i hold the maggies so dear,once you hear a non boxed speaker and lived with it for a while you realise how boxy speakers can sound even when you think the speaker in question cant be!
i did look a bit further but most info i found seem to reckon compensation circuits was needed so that killed it for me as science is a strong point with me,i try to understand but i seem to forget it all so quiclky....old age i guess.
smithie
thanks for your input,ill have to try and find out my amps specs,damping etc,not easy as there chnese so info is next to non-existant( ming-da finest).
funny enough i did try a open baffle,cant rember the baffle size as it was a while,i had the driver low down and the baffle slightly tilted back, i thought they was ok (certainly no bass boom) but felt that the sound had dips and peaks to it,no surprise really as there was no science to my experiment!
i so wanted to go this route as its one of the reasons i hold the maggies so dear,once you hear a non boxed speaker and lived with it for a while you realise how boxy speakers can sound even when you think the speaker in question cant be!
i did look a bit further but most info i found seem to reckon compensation circuits was needed so that killed it for me as science is a strong point with me,i try to understand but i seem to forget it all so quiclky....old age i guess.
smithie
smithie said:
I think you're really fine with the way you have the speakers for now, it's really a hit or miss if you do something else without getting more technical calculation of the basices. Most tools for DIY can be found on the web. Martins Mathcad worksheets give a pretty good estimate with normal shaped enclosures.
Hi
My current setup is JX92S in Jim Griffins mini-monitor driven by built-in GC.
Right now it is used as computer speakers and occasionally as speakers for the TV-set...
As said before I cannot integrate the speakers properly in the my small room in order to get decent sound.
For serious listening I use headphones driven from CD-player, and this sound WAY better than any speaker I ever heard...
JB
My current setup is JX92S in Jim Griffins mini-monitor driven by built-in GC.
Right now it is used as computer speakers and occasionally as speakers for the TV-set...
As said before I cannot integrate the speakers properly in the my small room in order to get decent sound.
For serious listening I use headphones driven from CD-player, and this sound WAY better than any speaker I ever heard...
JB
well your certainly getting your moneys worth out of those jx92s,they can never be called unversitile!
bet it breaks your heart not being able to set them up in a dedicated system,but by the sounds of it your more then happy with the headphones..something ive never really got on with!
on another note how do you find the gainclones,i no next to nothing on these,ie sound,where to get them,price etc,but was thinking if i use my jx150s for sub enhancements then maybe that could be a answer to power them leaving my valve monoblocks free for just the jx92.
all the best
smithie
bet it breaks your heart not being able to set them up in a dedicated system,but by the sounds of it your more then happy with the headphones..something ive never really got on with!
on another note how do you find the gainclones,i no next to nothing on these,ie sound,where to get them,price etc,but was thinking if i use my jx150s for sub enhancements then maybe that could be a answer to power them leaving my valve monoblocks free for just the jx92.
all the best
smithie
Smithie, there is a wealth of info available on the GC, just search the chip-amp forum.
Is it the Chinese Cayin/Spark amps you use ?
JB
Is it the Chinese Cayin/Spark amps you use ?
JB
hi thinkbad
yeh when the time comes and if i go the route with the jx150s then i shall be on the quest and looking into the gainclones and anything else that might do the trick.
but first i really want to sort my jx92 and valve combination out first,once im happy with that side of things then ill be focusing on the next weakest link in my chain that is my system.
regarding my amps,they are mingda mc-845c monoblocks and the mingda mcr7 pre-amp and not what you stated.
i really like them,dont know how they compare to the mainstream fair out there,theres alot of preduce against buying the chinese stuff,but ive had them over a yr,havent had to replace even one valve and i use them dailey,oh and they was at a price that i could actully afford,as i always wanted the 845se amp,but if you checkout the mainstream companys prices for such a thing then i would never of got one in my life!
did think about maybe building some....BUT THE VOLTAGE is to scarey to be mucking about with unless you know what your doing...which i dont!
smithie
yeh when the time comes and if i go the route with the jx150s then i shall be on the quest and looking into the gainclones and anything else that might do the trick.
but first i really want to sort my jx92 and valve combination out first,once im happy with that side of things then ill be focusing on the next weakest link in my chain that is my system.
regarding my amps,they are mingda mc-845c monoblocks and the mingda mcr7 pre-amp and not what you stated.
i really like them,dont know how they compare to the mainstream fair out there,theres alot of preduce against buying the chinese stuff,but ive had them over a yr,havent had to replace even one valve and i use them dailey,oh and they was at a price that i could actully afford,as i always wanted the 845se amp,but if you checkout the mainstream companys prices for such a thing then i would never of got one in my life!
did think about maybe building some....BUT THE VOLTAGE is to scarey to be mucking about with unless you know what your doing...which i dont!
smithie
right, there is no reason to underestimate the Chinese products, they use top-notch components and the build quality is excellent, the sound is fine and the price affordable.
When I get more time to experiment with my JX92 I will let you know how it turns out.
cheers
JB
When I get more time to experiment with my JX92 I will let you know how it turns out.
cheers
JB
yeah i love the stuff,got a e5 eastsound cd player to,if you havent heard about that then i think you will soon,got it direct from china,but now 3-4 uk companys are just taking it on board with sole rights...im waiting to see how much that privlage is going to cost the man in the street.
been all day on and off with these vtls but im coming to the conclusion that this desin might not be for me my system as all the tweaking,moving isnt giiving me the sound im ater....so that 8ltr enclosure idea is geetin closure!
ill keep you posted also.
happy listerning
smithie
been all day on and off with these vtls but im coming to the conclusion that this desin might not be for me my system as all the tweaking,moving isnt giiving me the sound im ater....so that 8ltr enclosure idea is geetin closure!
ill keep you posted also.
happy listerning
smithie
RAndyB said:
Good idea. I found the BSC from the website took too much air out of the sound. Several people have commented that the JX92S is very fussy about passive xover components.
What would a line level one look like? Anyone tried it?
Nardis said:
Hello all,
for BSC calculation for your box/baffle, try:
www.tolvan.com/edge/
I am using an active version at present - definite improvement.
smithie said:
I am currently driving the JX92 with TDA2794 chip amps - these do at least reproduce the full frequency range, the damping factor is not good, though. Have tried Maplin MOSFET amps - better bass, better damping, nasty 3rd harmonic distortion; next project is Rod Elliott's MOSFET amp. My (limited) experience of LM3875 (GC) is not good.
Jordan loudspeakers deserve better than chip amps IMHO.
Regards,
Andy
well the weekend of playing with the vtl design is over and i cant get a sound im happy with,so i think i shall try another enclosure,before i do i was thinking of giving the open baffle idea a try(that enclosure is easy to knock up).
has anyone any experience with this driver(jx92) in this design,if so what was the outcome,conclusion.
what would be a good size baffle to start with,any tips etc would be handy also.
many thanks
smithie
has anyone any experience with this driver(jx92) in this design,if so what was the outcome,conclusion.
what would be a good size baffle to start with,any tips etc would be handy also.
many thanks
smithie
smithie said:
Open baffles generally need to be away from the walls. I think will you to better with the mass loaded transmission lines which Martins mathcad worksheets sould to a good job simulating. Bob Brines (hope I spelled it right) seemed to have done some good work with them. Of course if you have lots of time to kill, sounds fun to try different solutions.
soongsc said:
Those ML/TLs need more box volume than 8 liters. i was also considering MLTL till i realised that any bob beyond 10L would get me thorw out of the house (internal 30"x5"x4").
BTW for those of you who have spent more time with the JX92 than I have are they good for HT/AV applications (along with a sub). What I mean is for $150 per speaker what are the alternates other than a $70 woofer mated to a $40 tweeter with a $30 XO.
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