Jordan JX92S Center Channel

[soongsc]

soongsc,

I wish I could control the XO freq. of my HT/AVR. If you know how i can change it (open it up and change some resistor or cap or both) let me know. It is a Marantz SR7000.

The present XO freq. is 100Hz. I would have prefered 80Hz or lower as the JX92 will not be stressed even if it is run down to 60Hz.

FleXoNotch looks interesting. Thanks. I still have not looked at it in detail as I am trying to get by with as few compoents as possible.

There are so many different models out there that I get confused. But normally if the low pass is done digitally, it is normally changeable in the DVD or AVR through the setup screens. Otherwise, it takes some time to go in and trace the circuit, which is easier if there is a maintenance manual. Normally changes in the circuit would just involve some resistor or capacitor changes.

>I am to believe that the surround material in teh Jordans also play a role in controlling the resonances that usually happen in metal coned drviers.

BTW how does the JX92 compare with the JX53/125 combo



Hi Navin

See my ramblings above re the last question. Both sound very electrostatic in nature.

Ted Jordan wrote several articles for the UK publication Wireless World, back in the 1970s, which covered the design of wide bandwidth metal cone speakers. Still applies today and it is interesing to see how few manufacturers are following his line of development, going for rigid cones and then having to sot out the resonance problems.

Didn't know I missed the such juicy articles, looks like a trip through the library archives would be interesting.

 

[soongsc]

Just forget the sub pre out on the main amp and build an active filter to go in front of your sub power amp. Feed it from the left and right pre-outs or speaker outs on the main amp.

Can you actually do this with the SR7000? I remember a few years back when we were using a Maranz ?9000? something, we just hooked up external amps, I wasn't aware you could loop them back in.

 

[richie00boy]

I'm assuming the sub has a separate power amp and the signal from the home cinema amp is line level. Therefore there is no need to loop anything back in.

 

[Colin]

>Didn't know I missed the such juicy articles, looks like a trip through the library archives would be interesting.


The articles featured in Wireless World November 1970 to January 1971. There was also an article about the development of the original 50mm module in Hi-Fi News April 1979.

 

[navin]

>Ted Jordan wrote several articles for the UK publication Wireless World, back in the 1970s, which covered the design of wide bandwidth metal cone speakers. Still applies today and it is interesing to see how few manufacturers are following his line of development, going for rigid cones and then having to sot out the resonance problems.

I remember these. but those were the days I was experimenting with multi way systems as I SPLs was my goal. Also India was a realy closed economy at that time so anything imported was difficult to come by. Philips used to make some nice drivers (12", 8", 5", a 2"dome and 2 1" domes) that i used in the 70s.

Just forget the sub pre out on the main amp and build an active filter to go in front of your sub power amp. Feed it from the left and right pre-outs or speaker outs on the main amp.

can do that but that signal wont be the 0.1 information it would be the L & R information. On some DVDs the inforamtion in the L & R is not the same as the 0.1 channel right?

 

[soongsc]

>Didn't know I missed the such juicy articles, looks like a trip through the library archives would be interesting.


The articles featured in Wireless World November 1970 to January 1971. There was also an article about the development of the original 50mm module in Hi-Fi News April 1979.

Thanks! It's nice to know people that read so much back then.

 

[richie00boy]

can do that but that signal wont be the 0.1 information it would be the L & R information. On some DVDs the inforamtion in the L & R is not the same as the 0.1 channel right?

The LFE/0.1 channel is a totally separate channel but, if you set the decoder to 'no sub' then it will route the LFE/0.1 channel info to the front left and right. IMO if you set it up like this it's best for movies and music as you can then set your sub/main crossover to be perfectly seamless as it sends the midbass of the LFE to the main speakers if your crossover is set well for large main speakers, so if your sub is close to you it's less noticeable on big LFE moments. Assuming of course your front left and right speakers are set to 'large'.

 

[navin]

You were right. From the Manual I unserstand that If I set my front speakers to Large and no Sub then it will route the LFE signal to the front speakers.

So what you are saying is that I should set my speakers to Large and No Sub and then take the output of the RCA for the front and use a Cossover for the sub. But how do I protect the JX92 from over excursion. what i really need to dois set roll off teh JX92 from the really low stuff (below 60Hz). right? the JX92 will still be fed from the HT/AV amp (Marantz SR7000).

 

[richie00boy]

Yes you have that all right now. You may not really find an excursion problem with the JX92 because they roll off high enough naturally, give it a try and see what you think