Kappa 9 refurb

[nailzgun]

Well as I mentioned in my last thread I got the Kappa 9's home and was a little underwhelmed by the sound. The wood though is virtually mint (just a couple of spots of paint, now removed) and has been treated with a special finish my buddy makes himself. They positively glow.

The electronics is another thing though. I removed all the drivers and the cross-overs. One of the rear emits is cooked. All the other drivers read great on the multi-meter. I was truly surprised to find the woofers had been replaced with (new) factory units from Infinity. Even more surprising was the labels on the woofers. They were control woofers from the IRS series. accelerometer wires were snipped, but suddenly thoughts of servo controlled Kappa 9'ss ran through my head. Very coool.

I called the 'man' at Millersound to ask his opinion regarding this idea and he strongly advised against it. He also suggested that I check under the dust caps to see if there was a foam core filling the voice coil space that tremendously inhibits the drivers ability. This was used to stabilize the accelerometer in these drivers. No foam core and no internal wiring so Infinity had already done this. Mr. Miller also mentioned that the crossovers on the 9's were problematic, specifically the inductors used on the woofers and this was likely the place where my sound problems lie.

So now I have these stunning cabinets sans drivers and electronics. The cross-overs I initially thought to do myself but have access to some truly magical electronic technicians locally so I am sending them out. (The Sonic Frontiers gnomes are all local as is Dan Santoni who does my Threshold gear.) All of these guys are electronic artists who will upgrade these things mecilesssly.

I will also take the opportunity to replace the Wonder Wire with something more transparent internally.

Anyway I will keep you all abreast:scratch2: of my progress.

 

[Iagent]

Sounds to me like you will have a splendid set of Kappas in the end. I love my Kappa 8s, that I just bought but they too need work.

 

[Augy]

Well as I mentioned in my last thread I got the Kappa 9's home and was a little underwhelmed by the sound. The wood though is virtually mint (just a couple of spots of paint, now removed) and has been treated with a special finish my buddy makes himself. They positively glow.

The electronics is another thing though. I removed all the drivers and the cross-overs. One of the rear emits is cooked. All the other drivers read great on the multi-meter. I was truly surprised to find the woofers had been replaced with (new) factory units from Infinity. Even more surprising was the labels on the woofers. They were control woofers from the IRS series. accelerometer wires were snipped, but suddenly thoughts of servo controlled Kappa 9'ss ran through my head. Very coool.

I called the 'man' at Millersound to ask his opinion regarding this idea and he strongly advised against it. He also suggested that I check under the dust caps to see if there was a foam core filling the voice coil space that tremendously inhibits the drivers ability. This was used to stabilize the accelerometer in these drivers. No foam core and no internal wiring so Infinity had already done this. Mr. Miller also mentioned that the crossovers on the 9's were problematic, specifically the inductors used on the woofers and this was likely the place where my sound problems lie.

So now I have these stunning cabinets sans drivers and electronics. The cross-overs I initially thought to do myself but have access to some truly magical electronic technicians locally so I am sending them out. (The Sonic Frontiers gnomes are all local as is Dan Santoni who does my Threshold gear.) All of these guys are electronic artists who will upgrade these things mecilesssly.

I will also take the opportunity to replace the Wonder Wire with something more transparent internally.

Anyway I will keep you all abreast:scratch2: of my progress.

Nailsgun. Please keep me posted on your progress....I am specifically curious as to what these guys are going to charge to check out your crossovers. I also find it hard to believe that an inductor can be problematic (Unless I have it confused with something else) basically all it is is a coil of copper wire. Again I have heard a kappa 9 that was not bi amped and the bass was very thin. Mine are bi amped and plenty of bass. What a difference it made.

 

[rabbit]

Nailsgun. Please keep me posted on your progress....I am specifically curious as to what these guys are going to charge to check out your crossovers. I also find it hard to believe that an inductor can be problematic (Unless I have it confused with something else) basically all it is is a coil of copper wire. Again I have heard a kappa 9 that was not bi amped and the bass was very thin. Mine are bi amped and plenty of bass. What a difference it made.

I was going to say the same thing. Unless there is a shorted turn what else could go wrong with the inductors ??

Do you have any pictures of your progress ??

 

[rroobbcc]

I will also once again add my voice to those who advocate bi-amping 9 Kappas. You won't be able to experience them at their best until you do.

 

[junkaudio]

biamp or die ,btw the rear tweeter has not mutch effect in the overall sound

 

[nailzgun]

I was going to say the same thing. Unless there is a shorted turn what else could go wrong with the inductors ??

Do you have any pictures of your progress ??

The iron core inductors that Infinity used with these speakers short out causing grief. It was not something I would have looked for that's for sure. Also here are some pics of my Infinity's. My Ren's in the living room, the new 9's and the 7's they will be replacing soon.

 

[Augy]

The iron core inductors that Infinity used with these speakers short out causing grief. It was not something I would have looked for that's for sure. Also here are some pics of my Infinity's. My Ren's in the living room, the new 9's and the 7's they will be replacing soon.

Hope you getum fixed up I definatly want to hear how the kappa9 compares to the ren 90 ....Only if you power them right though.

 

[Spasticteapot]

Hmm. Sounds like there's a pretty penny to be made making replacement Infinity crossovers out of proper parts.

Does anyone have links to the schematics?

 

[nailzgun]

Hmm. Sounds like there's a pretty penny to be made making replacement Infinity crossovers out of proper parts.

Does anyone have links to the schematics?

I don't have to make replacement crossovers just repair them. No different then having to rebuild the power supplies of older amps because the electrolytics get tired and new diodes and capacitors are faster. In the end you have equipment that cost very little comparatively to what a new system costs and sounds unbelievable.

The schematics are at
http://www.infinity-classics.de/infinity/technik/manuals/Kappa_9_technical_sheet.pdf

 

[rabbit]

I don't have to make replacement crossovers just repair them. No different then having to rebuild the power supplies of older amps because the electrolytics get tired and new diodes and capacitors are faster. In the end you have equipment that cost very little comparatively to what a new system costs and sounds unbelievable.

The schematics are at
http://www.infinity-classics.de/infinity/technik/manuals/Kappa_9_technical_sheet.pdf

You'll find that the large value bipolar electros in the woofer section still measure ok. They seem to be of a good quality construction according to the ones used in my RS4.5's.

 

[nailzgun]

Well it's going to be a couple of weeks before the crossovers are done. (Parts and assistance). So I have been thinking about all your advice regarding bi-amping these speakers. I do have 2 Threshold S-500's that I can use, the second is currently driving my Ren 90's. My thoughts though tend toward using tubes for the upper end of these speakers.
I would like some ideas regarding necessary wattage for the mids tweeters section and opinions about whether active crossovers are necessary or not. As my pre-amp does not have dual line outs I will have to come up with some kind of alternative. Just splitting the cables doesn't feel right. Maybe some sort of Tube buffer with dual line outs?

Opinions please
Scott

 

[Augy]

Well it's going to be a couple of weeks before the crossovers are done. (Parts and assistance). So I have been thinking about all your advice regarding bi-amping these speakers. I do have 2 Threshold S-500's that I can use, the second is currently driving my Ren 90's. My thoughts though tend toward using tubes for the upper end of these speakers.
I would like some ideas regarding necessary wattage for the mids tweeters section and opinions about whether active crossovers are necessary or not. As my pre-amp does not have dual line outs I will have to come up with some kind of alternative. Just splitting the cables doesn't feel right. Maybe some sort of Tube buffer with dual line outs?

Opinions please
Scott

I guess the correct way would be to use an active crossover however I do not use one Bi amping mine. I rely on the speakers crossover system for the mids and highs. I also have two identical amps ( Nak PA-7 200wpc @ 8 ohm ) in a vertical bi amp configuration and it sounds beautiful. The highs are great too. Though at times I wish I had bigger amps for these. But the problem with these speakers is you really need about 2-4 k in amps to run a 1k speaker. Unless you use a pro DJ amp like a crown or qsc for woofer duty.

 

[rabbit]

I guess the correct way would be to use an active crossover however I do not use one Bi amping mine. I rely on the speakers crossover system for the mids and highs. I also have two identical amps ( Nak PA-7 200wpc @ 8 ohm ) in a vertical bi amp configuration and it sounds beautiful. The highs are great too. Though at times I wish I had bigger amps for these. But the problem with these speakers is you really need about 2-4 k in amps to run a 1k speaker. Unless you use a pro DJ amp like a crown or qsc for woofer duty.

This is not always the case. I use a Harman Kardon Signature Series PA2400 power amp to drive my RS4.5's with no problems. This amp is rated at 170 watts per channel into 8 ohms or 4 ohms depending on the impedance selector and has a high current capability of +/- 100 amps. Circuit wise this amp shares a lot of similarities with the classic top of the line Harman Kardon Citation XX and X-1 amps. It is a wide bandwidth low negative feedback design and it has 4 pairs of high speed Toshiba output transistors per channel and a fully cascoded complimentary differential FET input stage. The last one of these amps went on Ebay for about $200 A bargain by any measure and one of Harman Kardon's best kept secrets IMHO

I don't necessarily listen to my music at ear shattering levels but the HK delivers a well defined bass and goes low when the music demands it !! It easily reproduces transients at frightening levels on Mike Oldfield's Amarok and Blood Sweat and Tears with perfect clarity and without any strain !! I run the system for hours on end whilst I'm in another room and it never shuts down Also when I tried selecting between FLAT and CUT mode on the bass EQ switch I didn't find much difference because of the limits of the room size so I leave it on CUT mode which is easier on the amps although the impedance still drops down to two ohms instead of one.

Of course I would not recommend your common or garden variety power amps, integrated amps or receivers to drive the Infinities. They are just not designed for low impedance loads :nono:

Just out of Interest the Yamaha MX1000 power amp which some others have recommended in the past only has 3 pairs of 2SC3280/2SA1301 12 Amp 120 Watt Toshiba transistors in its output stage whereas the HK PA2400 has 4 pairs of 2SC3281/2SA1302 15 Amp 150 Watt transistors in its output stage

 

[Augy]

This is not always the case. I use a Harman Kardon Signature Series PA2400 power amp to drive my RS4.5's with no problems. This amp is rated at 170 watts per channel into 8 ohms or 4 ohms depending on the impedance selector and has a high current capability of +/- 100 amps. Circuit wise this amp shares a lot of similarities with the classic top of the line Harman Kardon Citation XX and X-1 amps. It is a wide bandwidth low negative feedback design and it has 4 pairs of high speed Toshiba output transistors per channel and a fully cascoded complimentary differential FET input stage. The last one of these amps went on Ebay for about $200 A bargain by any measure and one of Harman Kardon's best kept secrets IMHO

I don't necessarily listen to my music at ear shattering levels but the HK delivers a well defined bass and goes low when the music demands it !! It easily reproduces transients at frightening levels on Mike Oldfield's Amarok and Blood Sweat and Tears with perfect clarity and without any strain !! I run the system for hours on end whilst I'm in another room and it never shuts down Also when I tried selecting between FLAT and CUT mode on the bass EQ switch I didn't find much difference because of the limits of the room size so I leave it on CUT mode which is easier on the amps although the impedance still drops down to two ohms instead of one.

Of course I would not recommend your common or garden variety power amps, integrated amps or receivers to drive the Infinities. They are just not designed for low impedance loads :nono:

Just out of Interest the Yamaha MX1000 power amp which some others have recommended in the past only has 3 pairs of 2SC3280/2SA1301 12 Amp 120 Watt Toshiba transistors in its output stage whereas the HK PA2400 has 4 pairs of 2SC3281/2SA1302 15 Amp 150 Watt transistors in its output stage

Not sure how the 4.5's compare to the Kappa 9 on the impedence curves but I do know the Kappa's dip below 1 ohm on some frequencies.

 

[VintInfinity]

I run a Yamaha PC2002M up top (basically an M-2 ruggedized and set up for pro use) and a BGW 500D on the woofers.

I just use the 1/4" input/output loops on the Yamaha to send the signal to the BGW. No active crossover for me and it sounds great to my ears.

The PC2002M also worked fine full range.

 

[nailzgun]

I am thinking of using a SET tube amp for the upper range. There are 50 watt single endeds available that are not two outrageously priced. My Threshold S 500 II would run the woofers. I think that this should be enough for the mids and highs. Any thoughts?

 

[rabbit]

I am thinking of using a SET tube amp for the upper range. There are 50 watt single endeds available that are not two outrageously priced. My Threshold S 500 II would run the woofers. I think that this should be enough for the mids and highs. Any thoughts?

Those SET amplifiers usually have high output impedance, lots of distortion and hence produce lots of coloration. They are only really good for driving efficient horn speakers. As soon as they are called upon to drive a speaker with a complex impedance they produce lots of coloration and although this may be subjectively more impressive it probably is not doing your music justice

IMHO if I was you I would use the one Threshold amp to drive the whole speaker rather than bi-amping it. Set the bass EQ switch on the speakers to CUT because it won't make a lot of difference to the bottom end but it will represent an easier load for the amplifier

 

[nailzgun]

Just wondering, I'm sure the answer has been posted before but is there any audible difference to the bass when the switch is changed fro 'Normal' to 'Extended'?

 

[rabbit]

Just wondering, I'm sure the answer has been posted before but is there any audible difference to the bass when the switch is changed fro 'Normal' to 'Extended'?

Depends on how good your room is and how it reproduces low bass. If it is relatively small then you'd most likely be wasting amplifier power trying to reproduce the deepest bass that these speakers are capable of. In this case it is better to use cut mode which will represent an easier load to the amplifier. Simplest way to find out is to choose some music with lots of bottom end and switch between the two settings and then see if there is much of a difference