Hello,
I recently purchased some rare DLK ULMs (electrostats made by Janszen). I believe these were the same units used on the Z-II CF which I owned and sounded wonderful. I contacted Janszen to see if they had any information on the unit and unfortunately, they did not. He did tell me they should play down to around 800hz and have a 2nd order (single L/C) filter ahead of the signal step-up transformer that rolls off below 800 Hz. The capacitor is a 4.7uf but I am unsure of the inductor value.
I have wanted to use the Dayton RS225s for a while. I'm tempted to build two enclosures with two RS225s in each and the electrostats sitting on top, I really believe that has the potential to sound amazing.
•Would the RS225 or RS225P be better?
•For load, would getting (2) 8 ohm and wiring in parallel, along with the Janszen in parallel be the way to go? Or, (2) 4 ohm in series with the Janszen in parallel?
•I do not have much experience designing crossovers. I would think a simple 1st or 2nd order would work. My concern is all the variables...load resistance, desired Q, flattening the x-over hump where the two drivers meet, etc, all come into play and I am unsure how to start.
I recently purchased some rare DLK ULMs (electrostats made by Janszen). I believe these were the same units used on the Z-II CF which I owned and sounded wonderful. I contacted Janszen to see if they had any information on the unit and unfortunately, they did not. He did tell me they should play down to around 800hz and have a 2nd order (single L/C) filter ahead of the signal step-up transformer that rolls off below 800 Hz. The capacitor is a 4.7uf but I am unsure of the inductor value.
I have wanted to use the Dayton RS225s for a while. I'm tempted to build two enclosures with two RS225s in each and the electrostats sitting on top, I really believe that has the potential to sound amazing.
•Would the RS225 or RS225P be better?
•For load, would getting (2) 8 ohm and wiring in parallel, along with the Janszen in parallel be the way to go? Or, (2) 4 ohm in series with the Janszen in parallel?
•I do not have much experience designing crossovers. I would think a simple 1st or 2nd order would work. My concern is all the variables...load resistance, desired Q, flattening the x-over hump where the two drivers meet, etc, all come into play and I am unsure how to start.
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In what way?
Have you determined the sensitivity of the ULMs?
(For future reference..
RS225-8 86.8
RS225-4 91
RS225P-8A 89.1
RS225P-4A 92.9
In that case, moving on to you other question.
Dayton say the P is easier to cross due to the response, but I don't see a problem with either that way. They both seem to be suitable for crossing around 2k, maybe 3k if you're careful.
It's not straightforward to say. They have similar low frequency characteristics. The P is slightly more sensitive.
Dayton say the P is easier to cross due to the response, but I don't see a problem with either that way. They both seem to be suitable for crossing around 2k, maybe 3k if you're careful.
I don't know if there is any truth in this, but paper intrigues me as a more natural sounding material. My goal is the best sound quality, with good bass extension, as possible. I am leaning towards a sealed cabinet with two paralleled 8-ohm drivers in each.
Concerning the crossover, is a first or second-order recommended? If I do a second order, the tweeter phase typically has to be reversed, correct? I don't see why but hope reversing the polarity on the Janszen electrostats won't be an issue. Also, what style crossover? It seems the Linkwitz-Riley is used most often.
If the Janszens are in fact high-pass crossed at 800hz, using its LC network, what frequency is suggested for the RS225s for the flattest response?
I plan on using a calculator such as the below to find values and will purchase the largest gauge air core inductor that makes financial sense.
https://www.diyaudioandvideo.com/Calculator/SpeakerCrossover/
Concerning the crossover, is a first or second-order recommended? If I do a second order, the tweeter phase typically has to be reversed, correct? I don't see why but hope reversing the polarity on the Janszen electrostats won't be an issue. Also, what style crossover? It seems the Linkwitz-Riley is used most often.
If the Janszens are in fact high-pass crossed at 800hz, using its LC network, what frequency is suggested for the RS225s for the flattest response?
I plan on using a calculator such as the below to find values and will purchase the largest gauge air core inductor that makes financial sense.
https://www.diyaudioandvideo.com/Calculator/SpeakerCrossover/
You won't know whether you have second order, or Linkwitz Riley, or what frequency etc.. unless you combine it with the drivers' response. Most of your questions are impossible to answer without this or other information, and for the same reason using a calculator will only give you a starting point. If you're working without measurement then you'll simply have to improve as you go, trying things as you learn about what needs to be improved.
It is better damped, which may be useful if you plan to run it high. Many pro woofers are paper.
Second is usually a good choice, but it's easier to choose undesirable values when working by ear.. so be prepared to make mistakes.
You don't have to get those ones 
Besides once you have more than one of them, you have four values to try if you include putting them in series and parallel.
Some people also find parts with windings in electronic equipment that can be used, or they wind their own or modify existing inductors.
Besides once you have more than one of them, you have four values to try if you include putting them in series and parallel.Some people also find parts with windings in electronic equipment that can be used, or they wind their own or modify existing inductors.
