Pete B
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Status Replies posted by Pete B
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Hi Pete,
I just did a recap of Dynaco a25's which included your 1uF mod. Luckily I have two pairs so could A/B with the an original crossover. As expected there is a very nice increase in the top end and the addition of "air" as you say. The original cap was 4.7uF. It measured 5.2uF when removed. I replaced it with parallel 3.3uF and 1.8 uF Jantzen Standard-Z caps.
Would you have a moment to quickly explain the effect of the 1uF cap? My electronics is getting better but I'd like to hear your thoughts.
Thanks very much!
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I don't know where anyone made that comment but they are wrong it is 1.0 uF.
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Hi Pete,
I just did a recap of Dynaco a25's which included your 1uF mod. Luckily I have two pairs so could A/B with the an original crossover. As expected there is a very nice increase in the top end and the addition of "air" as you say. The original cap was 4.7uF. It measured 5.2uF when removed. I replaced it with parallel 3.3uF and 1.8 uF Jantzen Standard-Z caps.
Would you have a moment to quickly explain the effect of the 1uF cap? My electronics is getting better but I'd like to hear your thoughts.
Thanks very much!
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The tweeter level control provides some resistive attenuation. Remember/consider that a cap passes
high frequencies and the addition of the cap provides a path for the highest frequencies to in a sense
bypass the resistive loss. It can only lift the same amount that the resistors are attenuating so as you
turn up the level the effect will be less. You can bring the HF bypass to pass at a lower frequency by
increasing the size of the cap.
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Hi Pete,
I am in the process of repairing an old classic of mine. The Hafler DH-110. Like many I am having issues with the J112 switching FET. Yes, I could just replace it when it fails but I would prefer a better more permanent solution. I would like to eliminate the J112 and modify the circuit with a high quality relay. I have read from a really old post that you have done this mod. If you don't mind would you care to share how you did it. I did not see a post anywhere on this. I studied the circuit but I am not seeing how do do it even though it looks like a simple solution. You can send me an email as well.
mike.kehr1@gmail.com
Thanks in Advance,
Mike
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Hi, I thought about doing that but never got around to it.
I removed the J112 s and am now very careful about the power up/down sequence
until I do the relay mod.
Thanks for your interest, Pete
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I did not want to divert the thread from cones vs domes and it was tending toward a personal advice column with me seeking answers I am not sure others would care about.
I am not a speaker builder. In the simplest form my question is which cone driver size will give max dispersion in the 200 to 4000hz range?
My reason for asking can be found in these threads.
http://www.classicspeakerpages.net/IP.Board/index.php?/topic/9588-baar-lst-hybrid-blast-stack/
There is no need to read the whole thing just look at the photos but, you should know that all 8 mid&tweet drivers per side are equalized and have their combined output balanced to the woofer. This is not a bunch of speakers running wide open to get the biggest, loudest sound.
This started out as a powered subwoofer project and morphed into this hybrid. I have standard setups of AR9s and 3as which I like but I now listen to this system more than anything else. What I intend to do this week is simplify it. I will eiminate the sound of the AR58 mid and tweeter by using a second Crown DSP amp to turn the 58 into a woofer only system. The satellite stack configuration will change and be rebalanced and equalized. If I don’t hear what I expect then I will restore the system to its current klugier config and move the amp to another system.
The satellites are 5.25” Bostons but they are so cheap and easy to find that I have been thinking that perhaps a 6” would be better to crossover even lower and get the woofer completely out of the female voice range but I didn’t want to sacrifice dispersion for a lower crossover and that is really the root of my question to you.
I have never liked the beaminess of satellite speakers but know they can be competent performers above the mid bass level. My original idea was to do this with powered subs but they are too tricky for my taste and quite by accident I found this approach can be very effective if you have the spare hardware sitting around.
I have done internet searches looking for others trying to accomplish the same thing with no luck otherwise I would be trying to talk to them. I have found plenty of diy line arrays but that is not what this is. If I am trying to emulate anything it would be an LST.
Anyway, I think I have explained why I am asking and only had the single question about driver size and dispersion.
Thanks
Frank
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People who are in the wide dispersion vintage AR camp are "illuminating" their probably
too small (in my opinion) rooms with sound. I am not in that camp as I believe that small
rooms are bad for good sound. I do all critical listening in the sweet spot and I listen to a
lot of vocal performers who I want placed center, between the speakers. I listen with
speakers 3 or more feet from the wall behind them. Sure, I also listen well off axis when
the music is just for background listening. I don't expect that I'd be an AR LST lover, since
they also "illuminate" the side walls though I've not had a pair in my home.
I think you and I are after different goals.
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I did not want to divert the thread from cones vs domes and it was tending toward a personal advice column with me seeking answers I am not sure others would care about.
I am not a speaker builder. In the simplest form my question is which cone driver size will give max dispersion in the 200 to 4000hz range?
My reason for asking can be found in these threads.
http://www.classicspeakerpages.net/IP.Board/index.php?/topic/9588-baar-lst-hybrid-blast-stack/
There is no need to read the whole thing just look at the photos but, you should know that all 8 mid&tweet drivers per side are equalized and have their combined output balanced to the woofer. This is not a bunch of speakers running wide open to get the biggest, loudest sound.
This started out as a powered subwoofer project and morphed into this hybrid. I have standard setups of AR9s and 3as which I like but I now listen to this system more than anything else. What I intend to do this week is simplify it. I will eiminate the sound of the AR58 mid and tweeter by using a second Crown DSP amp to turn the 58 into a woofer only system. The satellite stack configuration will change and be rebalanced and equalized. If I don’t hear what I expect then I will restore the system to its current klugier config and move the amp to another system.
The satellites are 5.25” Bostons but they are so cheap and easy to find that I have been thinking that perhaps a 6” would be better to crossover even lower and get the woofer completely out of the female voice range but I didn’t want to sacrifice dispersion for a lower crossover and that is really the root of my question to you.
I have never liked the beaminess of satellite speakers but know they can be competent performers above the mid bass level. My original idea was to do this with powered subs but they are too tricky for my taste and quite by accident I found this approach can be very effective if you have the spare hardware sitting around.
I have done internet searches looking for others trying to accomplish the same thing with no luck otherwise I would be trying to talk to them. I have found plenty of diy line arrays but that is not what this is. If I am trying to emulate anything it would be an LST.
Anyway, I think I have explained why I am asking and only had the single question about driver size and dispersion.
Thanks
Frank
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The best thing would be to have the HT in 2ch with simply delay to the rears, not sure if
most can do this.
I believe that we are after different goals, most want precise imaging with envelopment
that provides the sense of a large space.
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I did not want to divert the thread from cones vs domes and it was tending toward a personal advice column with me seeking answers I am not sure others would care about.
I am not a speaker builder. In the simplest form my question is which cone driver size will give max dispersion in the 200 to 4000hz range?
My reason for asking can be found in these threads.
http://www.classicspeakerpages.net/IP.Board/index.php?/topic/9588-baar-lst-hybrid-blast-stack/
There is no need to read the whole thing just look at the photos but, you should know that all 8 mid&tweet drivers per side are equalized and have their combined output balanced to the woofer. This is not a bunch of speakers running wide open to get the biggest, loudest sound.
This started out as a powered subwoofer project and morphed into this hybrid. I have standard setups of AR9s and 3as which I like but I now listen to this system more than anything else. What I intend to do this week is simplify it. I will eiminate the sound of the AR58 mid and tweeter by using a second Crown DSP amp to turn the 58 into a woofer only system. The satellite stack configuration will change and be rebalanced and equalized. If I don’t hear what I expect then I will restore the system to its current klugier config and move the amp to another system.
The satellites are 5.25” Bostons but they are so cheap and easy to find that I have been thinking that perhaps a 6” would be better to crossover even lower and get the woofer completely out of the female voice range but I didn’t want to sacrifice dispersion for a lower crossover and that is really the root of my question to you.
I have never liked the beaminess of satellite speakers but know they can be competent performers above the mid bass level. My original idea was to do this with powered subs but they are too tricky for my taste and quite by accident I found this approach can be very effective if you have the spare hardware sitting around.
I have done internet searches looking for others trying to accomplish the same thing with no luck otherwise I would be trying to talk to them. I have found plenty of diy line arrays but that is not what this is. If I am trying to emulate anything it would be an LST.
Anyway, I think I have explained why I am asking and only had the single question about driver size and dispersion.
Thanks
Frank
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Yes you would change the polarity of the rear facing pair and it has no impact at all
on the impedance. That will get you a dipole pattern, I expect that they will work much
better with 2-6 feet behind the speakers if you can do that.
Most modern HT receivers allow you to add delay to the rear channels, that might get
you something similar to what was done in the MGC if you want to try that.
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I did not want to divert the thread from cones vs domes and it was tending toward a personal advice column with me seeking answers I am not sure others would care about.
I am not a speaker builder. In the simplest form my question is which cone driver size will give max dispersion in the 200 to 4000hz range?
My reason for asking can be found in these threads.
http://www.classicspeakerpages.net/IP.Board/index.php?/topic/9588-baar-lst-hybrid-blast-stack/
There is no need to read the whole thing just look at the photos but, you should know that all 8 mid&tweet drivers per side are equalized and have their combined output balanced to the woofer. This is not a bunch of speakers running wide open to get the biggest, loudest sound.
This started out as a powered subwoofer project and morphed into this hybrid. I have standard setups of AR9s and 3as which I like but I now listen to this system more than anything else. What I intend to do this week is simplify it. I will eiminate the sound of the AR58 mid and tweeter by using a second Crown DSP amp to turn the 58 into a woofer only system. The satellite stack configuration will change and be rebalanced and equalized. If I don’t hear what I expect then I will restore the system to its current klugier config and move the amp to another system.
The satellites are 5.25” Bostons but they are so cheap and easy to find that I have been thinking that perhaps a 6” would be better to crossover even lower and get the woofer completely out of the female voice range but I didn’t want to sacrifice dispersion for a lower crossover and that is really the root of my question to you.
I have never liked the beaminess of satellite speakers but know they can be competent performers above the mid bass level. My original idea was to do this with powered subs but they are too tricky for my taste and quite by accident I found this approach can be very effective if you have the spare hardware sitting around.
I have done internet searches looking for others trying to accomplish the same thing with no luck otherwise I would be trying to talk to them. I have found plenty of diy line arrays but that is not what this is. If I am trying to emulate anything it would be an LST.
Anyway, I think I have explained why I am asking and only had the single question about driver size and dispersion.
Thanks
Frank
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Here is a review of the AR MGC-1, I also have the AES paper on it:
https://www.stereophile.com/content/acoustic-research-mgc-1-loudspeaker
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I did not want to divert the thread from cones vs domes and it was tending toward a personal advice column with me seeking answers I am not sure others would care about.
I am not a speaker builder. In the simplest form my question is which cone driver size will give max dispersion in the 200 to 4000hz range?
My reason for asking can be found in these threads.
http://www.classicspeakerpages.net/IP.Board/index.php?/topic/9588-baar-lst-hybrid-blast-stack/
There is no need to read the whole thing just look at the photos but, you should know that all 8 mid&tweet drivers per side are equalized and have their combined output balanced to the woofer. This is not a bunch of speakers running wide open to get the biggest, loudest sound.
This started out as a powered subwoofer project and morphed into this hybrid. I have standard setups of AR9s and 3as which I like but I now listen to this system more than anything else. What I intend to do this week is simplify it. I will eiminate the sound of the AR58 mid and tweeter by using a second Crown DSP amp to turn the 58 into a woofer only system. The satellite stack configuration will change and be rebalanced and equalized. If I don’t hear what I expect then I will restore the system to its current klugier config and move the amp to another system.
The satellites are 5.25” Bostons but they are so cheap and easy to find that I have been thinking that perhaps a 6” would be better to crossover even lower and get the woofer completely out of the female voice range but I didn’t want to sacrifice dispersion for a lower crossover and that is really the root of my question to you.
I have never liked the beaminess of satellite speakers but know they can be competent performers above the mid bass level. My original idea was to do this with powered subs but they are too tricky for my taste and quite by accident I found this approach can be very effective if you have the spare hardware sitting around.
I have done internet searches looking for others trying to accomplish the same thing with no luck otherwise I would be trying to talk to them. I have found plenty of diy line arrays but that is not what this is. If I am trying to emulate anything it would be an LST.
Anyway, I think I have explained why I am asking and only had the single question about driver size and dispersion.
Thanks
Frank
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With regard to your experiment there, it looks like you are on the right track to getting something close to an AR LST.
It is a very complicated question if you were to ask me how to improve on what you're doing. Should I assume that AR was correct in the thinking that wide dispersion should be a goal? Let me offer some food for thought, my opinion on home listening rooms is that all of the boundaries close to the speakers, say at the same end of the room as the speakers are too close to provide "good" sound and therefore I've never been interested in omnidirectional or Bipolar speakers. This is because those close boundaries and small rooms do not provide enough delay in the reflected sound to avoid harming the first arrival. If you read about the perception of sound there is a sweet spot for reverberation that is in the 25 - 35 ms time range which requires a much larger room or electronic delay to rear or ambience (wall bounce) speakers. Look up the AR MGC designed by Ken Kantor, the front firing speakers were made directional with foam horns, and the rear firing speakers were driven with delay and a dedicated amp.
Consider that we've had in the market:
AR with wide dispersion as a goal
Various fads in the 1960 - 70s for omnidirectional sound,
Dipole sound with a figure 8 radiation pattern, Magnepan, Linkwitz, Quads, etc.
Large format 10 - 12" full range systems that strongly beam,
It is interesting that for the last 20 or more years Linkwitz has been promoting figure 8 radiation pattern dipole speakers including dipole bass. Then he designed the low cost Pluto that is omnidirectional below 1 KHz and with a 1.5" driver for the rest of the range. He claims that this gets you something like 90% of what his high priced dipoles can do. Perhaps what matters more than the radiation pattern is a proper, realistic sounding voicing. Linkwitz has said lately, in the last 5 years or so, that early reflections are important for good sound yet I don't see how this fits with the dipole radiation pattern of his high end systems.
I have several friends with 12" full range speakers, some dipole, and obviously they are very directional which should remove much of the side wall reflections. I've concluded that removing, most of, those early reflections is what gives them a very tranparent sound that I would not expect from a large bulky driver.
I get very pleasing sound from big conventional front firing 3-way systems and don't feel that I have any need for dipole or super wide dispersion tweeters.
This is a very complex subject that depends on your room and goals for your system, so perhaps I've given you some food for thought.
You might try facing one of the top range speakers toward the wall behind the speakers and drive it with a delayed version of the fronts as was done in the MGC if you are open for more experimentation.
You could also face your small mains back to back and wire them out of phase if you are interested in dipole sound with or without the delayed ambience speakers.
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I did not want to divert the thread from cones vs domes and it was tending toward a personal advice column with me seeking answers I am not sure others would care about.
I am not a speaker builder. In the simplest form my question is which cone driver size will give max dispersion in the 200 to 4000hz range?
My reason for asking can be found in these threads.
http://www.classicspeakerpages.net/IP.Board/index.php?/topic/9588-baar-lst-hybrid-blast-stack/
There is no need to read the whole thing just look at the photos but, you should know that all 8 mid&tweet drivers per side are equalized and have their combined output balanced to the woofer. This is not a bunch of speakers running wide open to get the biggest, loudest sound.
This started out as a powered subwoofer project and morphed into this hybrid. I have standard setups of AR9s and 3as which I like but I now listen to this system more than anything else. What I intend to do this week is simplify it. I will eiminate the sound of the AR58 mid and tweeter by using a second Crown DSP amp to turn the 58 into a woofer only system. The satellite stack configuration will change and be rebalanced and equalized. If I don’t hear what I expect then I will restore the system to its current klugier config and move the amp to another system.
The satellites are 5.25” Bostons but they are so cheap and easy to find that I have been thinking that perhaps a 6” would be better to crossover even lower and get the woofer completely out of the female voice range but I didn’t want to sacrifice dispersion for a lower crossover and that is really the root of my question to you.
I have never liked the beaminess of satellite speakers but know they can be competent performers above the mid bass level. My original idea was to do this with powered subs but they are too tricky for my taste and quite by accident I found this approach can be very effective if you have the spare hardware sitting around.
I have done internet searches looking for others trying to accomplish the same thing with no luck otherwise I would be trying to talk to them. I have found plenty of diy line arrays but that is not what this is. If I am trying to emulate anything it would be an LST.
Anyway, I think I have explained why I am asking and only had the single question about driver size and dispersion.
Thanks
Frank
-
With regard to your experiment there, it looks like you are on the right track to getting something close to an AR LST.
It is a very complicated question if you were to ask me how to improve on what you're doing. Should I assume that AR was correct in the thinking that wide dispersion should be a goal? Let me offer some food for thought, my opinion on home listening rooms is that all of the boundaries close to the speakers, say at the same end of the room as the speakers are too close to provide "good" sound and therefore I've never been interested in omnidirectional or Bipolar speakers. This is because those close boundaries and small rooms do not provide enough delay in the reflected sound to avoid harming the first arrival. If you read about the perception of sound there is a sweet spot for reverberation that is in the 25 - 35 ms time range which requires a much larger room or electronic delay to rear or ambience speakers. Look up the AR MGC designed by Ken Kantor, the front firing speakers were made directional with foam horns, and the rear firing speakers were driven with delay and a dedicated amp.
Consider that we've had in the market:
AR with wide dispersion as a goal
Various fads in the 1960 - 70s for omnidirectional sound,
Dipole sound with a figure 8 radiation pattern, Magnepan, Linkwitz, Quads, etc.
Large format 10 - 12" full range systems that strongly beam,
It is interesting that for the last 20 or more years Linkwitz has been promoting figure 8 radiation pattern dipole speakers including dipole bass. Then he designed the low cost Pluto that is omnidirectional below 1 KHz and with a 1.5" driver for the rest of the range. He claims that this gets you something like 90% of what his high priced dipoles can do. Perhaps what matters more than the radiation pattern is a proper, realistic sounding voicing. Linkwitz has said lately, in the last 5 years or so, that early reflections are important for good sound yet I don't see how this fits with the dipole radiation pattern of his high end systems.
I have several friends with 12" full range speakers, some dipole, and obviously they are very directional which should remove much of the side wall reflections. I've concluded that removing, most of, those early reflections is what gives them a very tranparent sound that I would not expect from a large bulky driver.
I get very pleasing sound from big conventional front firing 3-way systems and don't feel that I have any need for dipole or super wide dispersion tweeters.
This is a very complex subject that depends on your room and goals for your system, so perhaps I've given you some food for thought.
You might try facing one of the top range speakers toward the wall behind the speakers and drive it with a delayed version of the fronts as was done in the MGC if you are open for more experimentation.
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I did not want to divert the thread from cones vs domes and it was tending toward a personal advice column with me seeking answers I am not sure others would care about.
I am not a speaker builder. In the simplest form my question is which cone driver size will give max dispersion in the 200 to 4000hz range?
My reason for asking can be found in these threads.
http://www.classicspeakerpages.net/IP.Board/index.php?/topic/9588-baar-lst-hybrid-blast-stack/
There is no need to read the whole thing just look at the photos but, you should know that all 8 mid&tweet drivers per side are equalized and have their combined output balanced to the woofer. This is not a bunch of speakers running wide open to get the biggest, loudest sound.
This started out as a powered subwoofer project and morphed into this hybrid. I have standard setups of AR9s and 3as which I like but I now listen to this system more than anything else. What I intend to do this week is simplify it. I will eiminate the sound of the AR58 mid and tweeter by using a second Crown DSP amp to turn the 58 into a woofer only system. The satellite stack configuration will change and be rebalanced and equalized. If I don’t hear what I expect then I will restore the system to its current klugier config and move the amp to another system.
The satellites are 5.25” Bostons but they are so cheap and easy to find that I have been thinking that perhaps a 6” would be better to crossover even lower and get the woofer completely out of the female voice range but I didn’t want to sacrifice dispersion for a lower crossover and that is really the root of my question to you.
I have never liked the beaminess of satellite speakers but know they can be competent performers above the mid bass level. My original idea was to do this with powered subs but they are too tricky for my taste and quite by accident I found this approach can be very effective if you have the spare hardware sitting around.
I have done internet searches looking for others trying to accomplish the same thing with no luck otherwise I would be trying to talk to them. I have found plenty of diy line arrays but that is not what this is. If I am trying to emulate anything it would be an LST.
Anyway, I think I have explained why I am asking and only had the single question about driver size and dispersion.
Thanks
Frank
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Your question:
"I am not a speaker builder. In the simplest form my question is which cone driver size will give max dispersion in the 200 to 4000hz range?"
Obviously, the smaller the better, but seeing what you are trying to do and taking the crossover point into consideration, 4.5 - 5.25" would be my answer. I read into this that your goal is to mimic, as close as possible, the wide dispersion of the 1.5" AR dome mid.
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I did not want to divert the thread from cones vs domes and it was tending toward a personal advice column with me seeking answers I am not sure others would care about.
I am not a speaker builder. In the simplest form my question is which cone driver size will give max dispersion in the 200 to 4000hz range?
My reason for asking can be found in these threads.
http://www.classicspeakerpages.net/IP.Board/index.php?/topic/9588-baar-lst-hybrid-blast-stack/
There is no need to read the whole thing just look at the photos but, you should know that all 8 mid&tweet drivers per side are equalized and have their combined output balanced to the woofer. This is not a bunch of speakers running wide open to get the biggest, loudest sound.
This started out as a powered subwoofer project and morphed into this hybrid. I have standard setups of AR9s and 3as which I like but I now listen to this system more than anything else. What I intend to do this week is simplify it. I will eiminate the sound of the AR58 mid and tweeter by using a second Crown DSP amp to turn the 58 into a woofer only system. The satellite stack configuration will change and be rebalanced and equalized. If I don’t hear what I expect then I will restore the system to its current klugier config and move the amp to another system.
The satellites are 5.25” Bostons but they are so cheap and easy to find that I have been thinking that perhaps a 6” would be better to crossover even lower and get the woofer completely out of the female voice range but I didn’t want to sacrifice dispersion for a lower crossover and that is really the root of my question to you.
I have never liked the beaminess of satellite speakers but know they can be competent performers above the mid bass level. My original idea was to do this with powered subs but they are too tricky for my taste and quite by accident I found this approach can be very effective if you have the spare hardware sitting around.
I have done internet searches looking for others trying to accomplish the same thing with no luck otherwise I would be trying to talk to them. I have found plenty of diy line arrays but that is not what this is. If I am trying to emulate anything it would be an LST.
Anyway, I think I have explained why I am asking and only had the single question about driver size and dispersion.
Thanks
Frank
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Hi Frank, let me look that all over and digest it.
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Greetings Pete!
Saw your picture of restored Dynacos.
I have now Dynaco A25, Scandyna A25X and Scandyna A45X, all of them need to be restored.
Wanna ask you - how you treated rubber surrounding to get it looks new and shiny?-
Why, just to clean it? We are fairly certain that a few types of rubber have been used for edges
and I'm not certain that Acetone is safe for all types.
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Greetings Pete!
Saw your picture of restored Dynacos.
I have now Dynaco A25, Scandyna A25X and Scandyna A45X, all of them need to be restored.
Wanna ask you - how you treated rubber surrounding to get it looks new and shiny?-
That was a big mistake on my part, I used WD40 and later learned that it has a very
strong solvent in it. I don't use it anymore for speaker edges.
Wish I had a better answer.
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