[ka7niq]

I assembled speakers for Brian for some time & quite a few of my suggestions have found their way into people's speakers/homes.  I also designed speakers for people as interesting as a first cellist for the SF Ballet. 

The only ribbon w/ QSO is the 626R (Special biwire/biamp models sold in the past on my special orders had no QSO.  B discontinued biamp 626R because of limited internal space.  I suppose he'd make them w/ OXO but I'm unsure if there's enough space behind the speaker for three pairs binding post inputs.)

The only 1st order is the bass low-pass.  An active xo should have a high-pass for the bass to aid in integrating w/ a sub.  The mid & tweeter high-pass are staggered dual-pole 1st order, equal to a sum total four normal 1st order poles of high-pass only per channel, five if you account for the bass high-pass.

The mid previously had a low-pass pole, but it might have been eliminated w/ the CDW eq.

I don't even want to add the number of stereo poles/channels the above non-existent active xo would require, maybe around 20 or so.  SOTA stereo preamps with a sum total of two channels cost $3k to $4k.  Do some basic math.  I get the definite idea you have not correctly calculated the cost of the non-existent active xo that is required. 

When a currently commercially available active xo w/ the above features is identified, that also beats the TRTs, there's a legitmate point.  Till then it's pure unadulterated & idealized conjecture, hypothesis, daydreaming &/or wishmaking.  Nothing wrong w/ that, but it's nice to know what we're talking about.     

 

Oh Yes Jim, it is wild conjecture, and that's the fun of it.
People at one time KNEW the world was flat, until Columbus, or the Vikings, proved it wasn't.

Since we are "conjecturing" here, let me just add this.
I would have NO problem using different crossover slopes then Brian uses.
I Do NOT believe in first order filters, as the only slope.
If they sound best, in a given application, fine, I will use them.

It is important to note that the VMPS RM 40 electronic crossover used 24 DB on the woofer roll off, and 6 db the rest of the way.

So, Brian "solved" that problem long ago.

I would like to see him take things to their logical conclusion, and provide a dedicated  3 way Active crosover for us RM 40 owners.

A new rear plate with 3 terminals would be nice too ?

But, this is ONLY good natured conjecture.
I am enjoying my passively bi amped RM 40's, at the moment .....

You would love them Jim, I am running them "Romeyn Style".
That is, with the pots wide open, except the tweeters.
I control things with amp level controls.

I find i feel less "guilty" doing it like this ....

For SOME reason, I was made to feel "guilty" by a friend who assured me that "no one runs the ribbons down so low"

[warnerwh]

It seems to me that for what active biamping costs someone could nearly upgrade to the RM/x speakers. That would be an improvement over the RM 30/40's I suspect.

I've been listening to my RM 40's with their old fashioned Auricaps for the past hour which are only passively biamped. Transparency is outstanding. Actually I've never heard a better system, and yes I should get out more. No doubt active biamping would improve the transparency, but how much? A few thousand dollars worth? My system retails for around 15k. 3k is 20% of my system's retail, much less what I actually paid which is probably around 8k just guessing. I'd suspect the cost of my system's cost is ball park middle land for the average RM 30 or 40 owner.

My point being that everyone has to take into consideration the improvement versus cost.  For a few extra thousand dollars spending it on state of the art room analysis and treatments may be a more worthy venture. I'd bet on it.

Brian has to consider what he offers to us as he needs to sell these options or not eat. Also he's tended heavily toward the high value part of the spectrum in his business decisions. I've not done the math myself but would heavily bet that Jim's estimates are correct. This means that only the most tweaky audiophile's will consider this option which is a very small part of the pool.

At this point if someone can afford it I'd say the best investment is passive biamping with some sort of tube or hybrid amp on top with a decent SS amp on bottom. The upper part of the spectrum with the lightning quick planars is the perfect match for the richness of tubes. Bass on these speakers is as tight, powerful and fast as you could want which usually only an SS amp can do properly.

Another problem with active biamping besides the high cost is the world of problems someone can get themselves into if they don't know exactly what they're doing. The passive crossovers are done by an expert with an obviously excellent ear. The amount of people who can do this properly are few.  This is just my opinion but I don't think most people should be messing with active biamping until they truly understand all that is going on and it's not simple.

[ka7niq]

It seems to me that for what active biamping costs someone could nearly upgrade to the RM/x speakers. That would be an improvement over the RM 30/40's I suspect.

I've been listening to my RM 40's with their old fashioned Auricaps for the past hour which are only passively biamped. Transparency is outstanding. Actually I've never heard a better system, and yes I should get out more. No doubt active biamping would improve the transparency, but how much? A few thousand dollars worth? My system retails for around 15k. 3k is 20% of my system's retail, much less what I actually paid which is probably around 8k just guessing. I'd suspect the cost of my system's cost is ball park middle land for the average RM 30 or 40 owner.

My point being that everyone has to take into consideration the improvement versus cost.  For a few extra thousand dollars spending it on state of the art room analysis and treatments may be a more worthy venture. I'd bet on it.

Brian has to consider what he offers to us as he needs to sell these options or not eat. Also he's tended heavily toward the high value part of the spectrum in his business decisions. I've not done the math myself but would heavily bet that Jim's estimates are correct. This means that only the most tweaky audiophile's will consider this option which is a very small part of the pool.

At this point if someone can afford it I'd say the best investment is passive biamping with some sort of tube or hybrid amp on top with a decent SS amp on bottom. The upper part of the spectrum with the lightning quick planars is the perfect match for the richness of tubes. Bass on these speakers is as tight, powerful and fast as you could want which usually only an SS amp can do properly.

Another problem with active biamping besides the high cost is the world of problems someone can get themselves into if they don't know exactly what they're doing. The passive crossovers are done by an expert with an obviously excellent ear. The amount of people who can do this properly are few.  This is just my opinion but I don't think most people should be messing with active biamping until they truly understand all that is going on and it's not simple.

Hello Warner!
Years ago, I owned a Pioneer Active 3 way electronic crossover.
It taught me a lot about speakers.
I had just as many speakers years ago, as I do now.
I have never grown up, I still like to play.

Years ago, I Tri amped or Bi amped old Vandersteens, Ess AMT 1's, Daybreaks, Polk's, and EV Interface D's, among many others.

Usually, but NOT always, I found I could get a much better sound then the passive versions, although with MUCH effort, and complexity.

An active crossover has many advantages, because it gives you control not only over the levels, but the crosover slopes as well.'
An active crossover is the highest expression of Brians wish that his speaker be completely tuneable.

I still think that one day we shall see an active crossover version of VMPS speakers.
It's only logical, because the performance advantages will be huge.

I too have my RM 40's passively bi amped at the moment, and they sound great.

But, I can never forget my experiences with the old Pioneer electronic crossover.

It's 2 AM here in Florida, and I need to sleep bro ...

I shall dream of an active VMPS, for now, and enjoy my RM 40's until then passively bi amped.

[Housteau]

For me, a large benefit of actively bi-amping is the ability to use a moderately powered tube amp for the mids and treble of a speaker.  When you bi amp passively each amp needs the power to drive the entire speaker.  It is too bad that the new powered version of the RM-40 does not have a high pass out from its integral bass amp.  That would do the trick.

What does the Super Tower III/SRE use?  If it is good enough for the top of the line system, It should be OK for the RM-40, shouldn't it?

"Audiophiles have long debated the virtues of tube vs. solid state design, with vociferous advocates on both sides of the debate. Transistors generally can deliver much more current than tubes and be directly coupled to the speaker. Tubes are more linear than semiconductors, however, and often produce more realistic mids and trebles. For these reasons, the SRE/ST3 is supplied with a 24 dB/octave electronic crossover. Tube fans could then hook up the Single-Ended Triodes, zero or low-feedback pentodes, or Class A EL34's (our favorite) for midrange and trebles only, while Solid-Staters can enjoy the diminished intermodulation distortion of true biamp or triamp operation. The great flexibility so achieved can be a true joy to the person wanting the maximum from his system. The passive crossover to the mid and trebles is outboard and is easily removed for service or updating, obviating the need to ever ship the speaker system itself back to the factory or service technician. The FET-input active crossover for the bass range boasts premium parts and a huge, 1,000,000uF/120W power supply, by far the heftiest power supply for line-level commercial gear ever."

[warnerwh]

Having both amps receive the entire input signal is no big deal for me. Using an amp that delivers 250wpc on top makes it a non issue. I understand my Fetvalve amp isn't as good in the bass department as a full SS amp is anyway. Another advantage of biamping being able to use an amp where it performs best.

I don't know if it matters but the power output by the amp is stopped by the crossover of the speakers. In effect the current needed by the woofers of my RM 40's isn't drawn from the Fetvalve amp. This should make life easier for it and it would seem allow more power to the upper part of the speakers from this amp than if it had to output the entire frequency spectrum. If someone could explain this better I'd appreciate it btw.

Either way not enough is lost to be concerned about. Not paying for or dealing with active crossovers is worth it to me. Besides I don't want to mess with the crossovers. Of course I understand how people could want to but for the average user I think don't think it's necessary.

With some tubes on top to the easy load the planar/ribbons provide it allows anybody who can hook up an amp to improve the sound of their speakers. The planar/ribbon amp doesn't have to drive the woofers which is the hardest part of our speakers to drive.

If I'm wrong someone please explain to me how please. Thanks

[John Casler]

So, Brian "solved" that problem long ago.

I would like to see him take things to their logical conclusion, and provide a dedicated  3 way Active crosover for us RM 40 owners.

Patience Weedhopper, patience

[woodsyi]

Warner,

I am sure you read this article by Rod Elliot but just in case you haven't read it in a while, I will link the article.
http://sound.westhost.com/bi-amp.htm
Obviously it is just one point of view, but he gives a good overview of the biamping process.
And then there is this Linkwitz dude who has an opinion on crossovers. http://www.linkwitzlab.com/crossovers.htm

[John Casler]

I think it is not considered but many of us are already "bi-amping" if we use sat/sub combinations, and the sub is self powered.

[Housteau]

I don't know if it matters but the power output by the amp is stopped by the crossover of the speakers. In effect the current needed by the woofers of my RM 40's isn't drawn from the Fetvalve amp. This should make life easier for it and it would seem allow more power to the upper part of the speakers from this amp than if it had to output the entire frequency spectrum. If someone could explain this better I'd appreciate it btw.

In a passive xover the unused frequency is filtered off, yes, but is has still been fully amplified before being filtered off.  It is still a load to the amp, just not a load to a particular driver.

That is not always a waste though.  Some higher powered SS amplifiers do prefer to be running closer to full tilt for their best sound.  On the other side of the spectrum, many tube amplifiers sound best at moderate power ratings running and being used in a less demanding role.  That is why some companies, such as Quicksilver, prefers to build moderately powered amps as opposed to the larger killer units you often see.

That is how I understand things to be.  If I am wrong here, please someone, set me straight.

[ka7niq]

So, Brian "solved" that problem long ago.

I would like to see him take things to their logical conclusion, and provide a dedicated  3 way Active crosover for us RM 40 owners.

Patience Weedhopper, patience

Ok Sen Sei.
I will keep partaking of the Anti Oxidants so i will be around to see it.
I watched and listened to "Starship Troopers" on the RM 40's last night.
I LOVE that Movie.
Of course, I have never heard the live sound of an Alien Insect sucking a human brain out, but it sounded pretty 'realistic' to me with "just" passively biamped RM 40's.

[ka7niq]

I don't know if it matters but the power output by the amp is stopped by the crossover of the speakers. In effect the current needed by the woofers of my RM 40's isn't drawn from the Fetvalve amp. This should make life easier for it and it would seem allow more power to the upper part of the speakers from this amp than if it had to output the entire frequency spectrum. If someone could explain this better I'd appreciate it btw.

In a passive xover the unused frequency is filtered off, yes, but is has still been fully amplified before being filtered off.  It is still a load to the amp, just not a load to a particular driver.

That is not always a waste though.  Some higher powered SS amplifiers do prefer to be running closer to full tilt for their best sound.  On the other side of the spectrum, many tube amplifiers sound best at moderate power ratings running and being used in a less demanding role.  That is why some companies, such as Quicksilver, prefers to build moderately powered amps as opposed to the larger killer units you often see.

That is how I understand things to be.  If I am wrong here, please someone, set me straight.

Housteau, you need to post more!
I have not had the pleasure of reading your posts before, but they are like a breath of fresh air.
You really hit the nail on the head about some big solid state amps sounding best at high /medium levels.

Case in point, I JUST bought some Klipsch Cornwalls, and just HAD to hook them up.
This IS an addiction, as you are well aware ...

The Cornwalls sounded absolutely dreadful on my highly modified Ashly FET 500 Mosfet amp.
It does 250 plus into 8, and over 500 into 4 ohms.
The Cornwalls were screechy, and harsh with this amp, yet on the RM 40's it sounds fine!

I substituted a  Luxman M 117 amp on the Cornwalls, and they were transformed.
Yet the Luxman is just OK on the RM 40's.

It has also been my experience that tube amps sound best if they are not working too hard.

That is the beauty of active bi amping.

Nice to meet you!
Chris

[Housteau]

Hello Chris,

I tend to be more of a lurker than poster, since often I do not have time to keep up with all things on-line.  However, I usually do find more time when I am away at work being paid to be doing something else .  Funny how that works out .

Also, since I don't presently own VMPS I do feel a little guilty about joining in on some discussions.  Although, I believe I have made my mind up that when it comes time for me to change, this is the direction I am going to move to.

You really hit the nail on the head about some big solid state amps sounding best at high /medium levels.

From this other thread, http://www.audiocircle.com/index.php?topic=32569.0 it appears that my ideas of the passive crossover were not correct.  Brian said that the load on the amp would in fact be reduced and it would not be as if the upper range amp was driving the entire speaker.

This is what is so nice about forums such as this.  There is always something new to learn and share.

[warnerwh]

Housteau: Just because you don't own Vmps speakers certainly doesn't mean you shouldn't be posting. You have been a wonderful guest and as you say that's the beauty of these forums is that we learn from each other. I've learned tons on just Audiocircle.

Like you I had been confused about biamping and it's effect on the power amps also. I still am somewhat because if the amp doesn't have to deliver full current to part of the load doesn't this mean it would have more available power? And if so, how much? Anybody who can answer this please chime in.

So yes you're more than welcome to be here. I always think it's best to keep and open mind and respect other people's opinions and tastes.  We're all certainly entitled to them.