My dream speaker - RS1b

[siramazing]

"The 1b manual said that it is not recommended to use an amp in the bridged mode."

That statement must be taken as gospel. Do not run a bridged amp into the 1b's IF YOU ARE USING THE INFINITY ACTIVE CROSSOVER. A bridged amp with the original active crossover may blow the amps and/or the speakers for the same reason it would if it were connected out of phase....the servo arrangement.

If you use a different crossover such as the DBX or the Rane, you can use a bridged amp without any difficulty, because you no longer have to deal with the servo in the Infinity active crossover.

Bill

[waudio]

Some progress in getting the 1b's to sing. See pics.

I painted the base of the mid/high panels with texture paint (with speckle of gold color particles) and then put on few layers of sprayed on poly. Then, I cleaned the panels and the bass towers with Touch of Orange rejuvenator and then polish them with the Touch of Orange beeswax. I also used the beeswax on the body of the emims.

The wires were soldered to the emims and emits - so I used a solder and solder wick to clean up the terminals. Afterward, I used a fine grade sand paper to roughen up the terminals before finally clean them with acetone. They should make good contacts now.

I measured each emim and took note its resistance value - and pair up ones with the same resistance values. All of them measured between 2.9 and 3.1 - and except of one pair, all of them can be paired up. For each pair, I installed them for the left and right at the same location.

The emits also look good - but I decided to use my remaining NOS emits. So, the emits are all brand new in this 1b's.

The original passive crossovers are quite a mess - I should have put a label on which wire goes to which emim. I need to take a look at the first owner's hand notes to figure it out. For now, I will be using a pair of the crossovers that I picked up from ebay. The seller (altarego) is very reputable and it was nice dealing with him. This pair has all the black wires - and comparing the face plate with the pics at the "infinity classics" site, I think it is the latest edition. Also upon comparing with the original crossovers, I also found that the original crossovers also have the same exact face plate - so I think they were also of the latest edition before the first owner decided to mod them.

The only remaining thing is to connect the wires. The new crossovers that I bought - are missing the terminal clips. They were also soldered to the emim/emit terminals (???). Why is this so common practice. I have been scouring parts express and the internet but could not yet find the suitable terminals that will fit the gauge of the wires.

I am really curious to hear how these 1b's sound. I recently put on a rather thick carpet (as area rug) to the floor to help with the reflection.

I found as much enjoyment in putting things together as listening to them. I found that I am becoming very picky in what I want to listen - I just could not listen to bad recordings - and that really limit to what I listen. I was so impressed with the Kappa 6 when I first got them. Then, after listening to the 2b's - I just could not enjoy listening to the Kappa 6. The sound stage is missing - or my ears are just so spoiled now.

More update in the next week or so.

[Ken Boyd]

Yup it appears you have the latest version of the RS-1b's, they look very nice. Looks like a great setup as far as the room looks pretty large that really makes a difference.

[StimpyWan]

http://app.audiogon.com/listings/inf...only-pair-made

I would have never sold them, if mine!!!

Originally Posted by Ken Boyd

I wonder what ever happen to that other AK members RS-1a's that he got that were brand new in the boxes, with walnut panels instead of oak, those were some really outstanding looking speakers.

[waudio]

Got a chance to open the last box that contained the active crossover. See attached pictures. It is heavily modded - with a separate power supply box - very heavy - containing all those big capacitors.

I never looked at the inside of the unmodded active 1b's crossover - so I assumed the the original capacitors in it were removed.

I am still having trouble to connect the wiring from the passive crossovers to the mid/hi drivers. The wire ends have solder on them and it increased the size from 12 ga to at least 10 ga. Cannot find female terminals that can take 10 ga wire. I am thinking about cutting the ends off and then attach the new terminals - however, even finding good quality female terminals that can take 12 ga wire is difficult. Any suggestion?

I am planning to test the active crossover today - using my kappa 6.1 (bi-ampable). I know it won't sound right but at least it may tell me if the active crossover is still in good shape after shipping. Any comment on whether this is a good or bad idea?

Thanks much.

[Ken Boyd]

I have three of the Active crossovers, here is a pic of one of mine, all three are much different from each others


http://www.audiokarma.org/forums/alb...pictureid=2922

[Bigerik]

Amazing read. Can't wait to hear your comments on the sound.

[waudio]

[QUOTE=Ken Boyd;5438430]I have three of the Active crossovers, here is a pic of one of mine, all three are much different from each others

Thank you Ken - I appreciate it. It seems that the seller took the "transformer" out and replaced it with the external power supply box.

Tomorrow, I will try to use this crossover with my kappa 6.1 - if this is a bad idea, then please let me know - otherwise, I will report either success or I have a blown Kappa and/or Carver. The Carver is non-inverting, so at least I have done some homework. I really have some reservation to plug that power supply box into the outlet. Those capacitors are bigger and more numerous than what I have seen inside my carvers.

[Ken Boyd]

[QUOTE=waudio;5438537]

Originally Posted by Ken Boyd

I have three of the Active crossovers, here is a pic of one of mine, all three are much different from each others

Thank you Ken - I appreciate it. It seems that the seller took the "transformer" out and replaced it with the external power supply box.

Tomorrow, I will try to use this crossover with my kappa 6.1 - if this is a bad idea, then please let me know - otherwise, I will report either success or I have a blown Kappa and/or Carver. The Carver is non-inverting, so at least I have done some homework. I really have some reservation to plug that power supply box into the outlet. Those capacitors are bigger and more numerous than what I have seen inside my carvers.

Yikes, I would be nervous about running a different brand of bass drivers than the one designed for the active crossover. For one thing those active crossovers are full of OP amps, that are pretty easy to fry, I had a pretty long talk with Bill Miller about them. He doesn't even like to fool with them any more because all it take is customer to hook it up wrong and you blow the op amps. If I recall there are at maybe 8 or more op amps in that crossover. I think the crossover uses some method of measuring resistance to the bass drivers to increase the amps current to correct the bass drivers. Unlike the Beta's which have a bass driver which measures the movement by a special accelerator thing. So if you hook up the unit to a driver set up that has some different resistance it might cause some real problems. I don't know this to be the case, but I personally would just hook it up to the speakers it was designed for, and when powering up keep the volume at zero, and then slowly bring it up. If you amp for the bass drivers have gain controls, I would also put them at minimum and then very slowly advance them up. The first pair of my RS-1b's I purchased the OEM crossover had a problem, the customer who sold them to me that something didn't sound right with the speakers but he never could figure out what it was. When I purchased them and hooked them up I knew instantly the problem was the bass was hardly there. I used a Rane active crossover and it was like night and day. I tore it apart and talked to a few people including Bill Miller who is suppose to have a pretty good rep on these speakers, he told me, replace all the op amps. That is what I did. Most are easy to get to, but their are a few on the back board which requires having to remove all the rear terminals to get to the board. When replacing the OP amps, they have to be placed in a certain direction, their is a small inditation on the top of the chips, make sure you place all of them if you ever have to, with the small dent in the right direction. I found plenty of sources for the right op amp on line, I purchased like 20 of them for pretty cheap money. Mr Miller told me that the op amps were the problem 9 times out of 10, so if yours has a problem thats where I would start.

As for your outboard power supply who ever modified it, sure beleived in a lot of extra capacitance, I would have never thougth that the crossover would need that much capacitance, but then what do I know.

[waudio]

Thanks much Ken! Disaster avoided. Well, then I will focus first on getting the passive crossovers connected.

[dcmaster]

Originally Posted by waudio

Got a chance to open the last box that contained the active crossover. See attached pictures. It is heavily modded - with a separate power supply box - very heavy - containing all those big capacitors.

I never looked at the inside of the unmodded active 1b's crossover - so I assumed the the original capacitors in it were removed.

Unfortunately, the images are very blurred. Was ich aber sofort erkenne, ist dass der "Bastler" dort wirklich extrem übertrieben hat mit dem Netzteil. Solche Elkos würde gut zu einer Leistungsendstufe passen, aber ganz sicher nicht zu dieser aktiven Frequenzweiche!

The active crossover may have a power consumption of 0.3 A for "+" and "-". That's it.

Originally Posted by waudio

I am still having trouble to connect the wiring from the passive crossovers to the mid/hi drivers. The wire ends have solder on them and it increased the size from 12 ga to at least 10 ga. Cannot find female terminals that can take 10 ga wire. I am thinking about cutting the ends off and then attach the new terminals - however, even finding good quality female terminals that can take 12 ga wire is difficult. Any suggestion?

I admit, these connectors are hard to come by, but they are there! You looking to good connectors for big cables? Although this is a German provider which is certainly in the U.S.. Here ist is.

http://www.ebay.de/itm/SinusLive-Set...item3f112bdafd

This is a set of 4.8 mm and 2.8 mm with 12 each in red and black and gold plated and for 4 mm ² cable.

An application of precisely these connectors you can see here on my own RS1B:

http://www.top-audio.de/service/ande...-bak3-nach.jpg

The complete story about this work you can read here (Sorry, only in german, use the google translator):

http://www.top-audio.de/service/andere/index-andere.htm

Take this link and then klick on the left side the button "Force Emim". There you will see an application with this connectors.

Originally Posted by waudio

I am planning to test the active crossover today - using my kappa 6.1 (bi-ampable). I know it won't sound right but at least it may tell me if the active crossover is still in good shape after shipping. Any comment on whether this is a good or bad idea?

Thanks much.

This is not a good idea! Be very carefull. The Kappa is not builded for this type of driving! It may be demage!

Klaus

[waudio]

Thank you so much Klaus! I really appreciate it. Those connectors are what I need.

Thanks again.

[waudio]

As promised earlier, see attached the documents that I got from the seller on the crossover modifications. They are not in order, as I am not sure which one is what.

[waudio]

More docs attached.

[dcmaster]

Originally Posted by waudio

As promised earlier, see attached the documents that I got from the seller on the crossover modifications. They are not in order, as I am not sure which one is what.

hi,
do you have the picture No. 1 (the active crossover) in a higher resolution? The image is too blurry, so that you can not see enough. The text parts and circuit details are very hard to read.

It is in any case very interesting.

Klaus