IRS killer vs FR30 speakers Part 1

In this first part Paul explains the use of servo control in woofers.

[@stimpy1226]

Darren and Chris are the Dynamic Duo of audio design right now IMHO

[@harryburnett7086]

Lol

[@davidcontini7217]

The best woofer of all time remains the one used by Marty McFly in Back to the Future.

[@HaraldMacGerhard]

Absolutely agree 😍😍😍

[@DodgyBrothersEngineering]

Once he gets it re-coned...

[@sevestan]

Fascinating talk Paul....like my old science teacher used to say, "onward and upward!"

[@AndyBHome]

I heard these prototypes at RMAF 2019 and they were pretty much the best speakers, it was pretty much the best stereo setup I've ever heard in my life, and that was next to an elevator shaft in a hotel conference room. I'd absolutely love to own those speakers, but I doubt they'd sound as good I'm my modest system and my small listening room. Regardless, if the FR1 is a significant improvement over these, I'd be completely blown away by them. I really hope I get a chance to hear the FR1 soon, even if they are a bit out of my price range.

[@stimpy1226]

The Bass columns on the Infinity RS1-B’s were incredibly tight and powerful. They could deliver gut punches with ease.

[@Stan_the_Belgian]

great view on servo woofers, have been wondering for a while why not everybody uses them, this explains it!

[@Enemji]

The more you control, the less freedom you have. That applies especially to Bass Woofers. I am glad to see Paul see the light.

[@JoeJ-8282]

I would absolutely LOVE to take those speakers there off your hands! I'll have to talk with you about that if I ever get up to your factory in person for a tour.

[@Golddragon214]

Even at your age Paul, you still learn things. Thank you for the explanation and discussing things most companies won't talk about.

[@RobertCookcx]

"Even at your age..." is not a great way to begin a compliment.

[@googoo-gjoob]

@@RobertCookcx , while you're correcting..... _compliment_

[@TrueLies23]

I just watched the servo talk with Chris this morning!

[@badd99]

Where is this at? Thanks

[@TrueLies23]

@@badd99 it's one of the "lunch with Paul" videos. Quite honestly I wish there was more of Chris on this channel.

[@user-od9iz9cv1w]

Interesting that Arnie's IRS killer is open baffle coupled with a servo sub. I did not realize this. I also find it interesting that he had fairly deep symmetric wings on the mid range. Watching Dennis at GR Research I have been convinced of the merits of one large wing together with a minimalist wing. As always, it would be so interesting to have really good recordings, A, B, C of the IRS, the killer and the FR30 in the same room on the same system so we could sort of hear the unique signature of each. Both Arnie's designs are dipols with servo sub's while Chris has run with SOTA bespoke drivers in a traditional box. So much here to talk about it. Much as I appreciate Paul, this would be a great deep dive opportunity for Chris to talk and back up statements with some well recorded sound clips.

[@DodgyBrothersEngineering]

Not sure I would call Arnie's speakers open baffle, they are more like bi-monopole. The tweeter at the very top are just two monopole tweeters facing in opposite directions in an enclosure the same as the mids. My ribbon tweeters are true dipoles as the sound comes off both sides of the ribbon.

[@ThinkingBetter]

It's a bit of a bummer that servo subs are so rare. Personally I prefer servo subs for their more precise undistorted reproduction of the deepest bass but few speaker designers know how to make great servo subwoofer design, or generally how to make a speaker active.

[@DodgyBrothersEngineering]

@@ThinkingBetter what do you mean by rare? They are readily available, but just not made by a lot of manufacturers.

[@ThinkingBetter]

@@DodgyBrothersEngineering Yes, I have a couple of Velodyne subs but Velodyne is no longer making subs. Rythmik is another brand that I will consider. So what brand would you recommend for a servo sub?

[@DodgyBrothersEngineering]

@@ThinkingBetter Velodyne made some great subs, a friend had one of their top end 18" units, and it was fairly impressive, but not cheap. Today I would probably lean towards the Rythmik for a couple of reasons. Firstly they offer complete subs, and secondly because they offer just the drivers and amps if you want to go that way, so no matter what kind of customer you are they have you covered. I especially like that in collaboration with Danny Ritchie they also offer an IB / OB driver, so you can create your own IB /OB configured sub. The possibilities are endless.

[@howardskeivys4184]

Paul, that line is an absolute classic. ‘You have to make an error, before you can correct it’. I recall another KZbin ‘high end’ audio reviewer, after he’d seriously upgraded his system, commenting that he had to unplug his DSP, which made a notable improvement to his system, prior to the upgrade. However post upgrade, the DSP caused a degradation in audio performance. I interpreted that as indicating that when specific performance standards are surpassed, the need for correction is greatly diminished! Your point about bass drivers, validates that. I think that in audio, costly solutions are often created to overcome or correct, non-existent, or at least, trivial problems!

[@JingoLoBa57]

I think your conclusion doesn’t fit here. In the early system the DSP was needed to correct or rather better balance and uplift that system. In the second it did not have the same issues and didn’t need the same solutions. Horses for courses. Both were valid situations.

[@budgetaudiophilelife-long5461]

🤗THANKS PAUL…GREAT STORY… showing that it’s the best time to be and AUDIOPHILE 😎😍😍😍

[@BiGDeE3]

Great insight Paul. Having watched prt 2 as well , thank you for sharing .

[@badd99]

Open baffle bass with servo is the real end game. No room boom. Super fast. Gr research servo open baffle subs are absolutely incredible and don't break the bank.

[@BastianUllr]

The limit of servo is at the extremes. That’s it. As long as you don’t got near the extremes, you are fine. Same with DSP limiters in the studio monitors. You get dynamic compression.

[@DodgyBrothersEngineering]

I don't know if servo open baffle is the be all and end all. I use some 18" Pro drivers in my open baffle and it has oodles of tight bass. Because the spiders are so big and stiff the cones barely moves. They might move 1mm when I am really on it. Because they move so little and they have no cabinet, they can return to rest faster than most other drivers.

[@fastrid]

I would really like longer videos from time to time. Maybe once a month? Ones where you can get more technical, flush ideas out, and we can learn something more accurately. Please?

[@CarlVanDoren61]

Magnepan 20.7s with Coda 16.0 👍

[@tee-jaythestereo-bargainph2120]

Those speakers look amazing

[@thefloop2813]

There's a clinton and a springfield in basically every state it seems. Shout out from Clinton, TN

[@yanivshef992]

Love it ! I learn so much , keep it coming 👍

[@richarddarr3381]

Bob Carver ' amazing speakers the woofers has a flatess bass response of Q..71 no one talked about this talking about the queue ratio

[@lcarliner]

With the exception of a double pair of KLH-9's, almost all woofer products render the timbre of the classical bowed string double bass instrument that of a ball park Hammond organ with just one tone slider in use. This instrument should be part of the test reproitre of audio critics and reviewers!

[@Roof_Pizza]

What would be your sample test track?

[@glenncurry3041]

Maggies are incredible at standup bass!

[@dmfdarkness]

I would love to know what tracks you would recommend to be able to most easily hear this.

[@dlmp70]

As others have asked, please recommend some test tracks for bass. Thank you.

[@robertjermantowicz8619]

I agree! One or two pairs of KLH Nines are a formidable bass system - not to mention the mids/highs!

[@cuttinchops]

Oh man, If your looking for a free rehoming, I will drop everything and head to Co now lol I would make sure to always have a great home :)

[@georgelien]

“You Dope !” 🤣🤣🤣

[@garysmith8455]

May I add? Who made the lowest distortion subwoofers in the early 90ies? Right, Velodyne! I still enjoy my F1500-R, it's musicality in a 2.1 system is still wonderful and plays very low! Yes, I understand it is NOT a powerhouse for movies, but for adding that very low extension with finesse in symphonic and pipeorgan recordings, it is still a first rate product even today.

[@dougstorace321]

I love my Velodyne servo sub, which I actually use for my virtual pipe organ!

[@dennisbohner6876]

Had one. It was the most unreliable product I've purchased over the last half-century.

[@garysmith8455]

@@dennisbohner6876 You bought a brand new F-1500-R back in 1995 as I did? What made it 'most' unreliable?? I never heard of any issues with them. The volume control got scratchy on my model, but that was discovered after over 26 years of use ! Other then that, the surround is in perfect shape, and it still makes great, musical bass for my listening enjoyment (O:

[@dennisbohner6876]

@@garysmith8455 Plate amps. Toting that 105 lbs of cabinet was a true burden. Since I am in Tampa Bay, lightning may have had a hand, though NOTHING else was affected. I dumped it. That was a GOOD choice. Admittedly when it functioned it was powerful and tuneful.

[@garysmith8455]

@@dennisbohner6876 Oh, ok, yes, lightning will raise a bit of hell with most anything, even if it is not plugged in the wall ! Ok on the PLATE amp. I didn't think that was a plate amp per say... Is it class D? This one has heat sinks hanging off the back of it...

[@ericberger6966]

The term "servo" is misleading for the most today, because a servo woofer means, driven by a servo(-motor), I call it "controlled". In case of IRS, analog controlled because it was at pre-digital times. In the early 1980s the German company Backes & Müller build expensive, fully active, analog controlled speakers, up to a BM20. They made big adoe and had a great attention in public and journals. They had good chassis, cone and cap, but they faced the discribed issues in sound. They had really power and a impressive impuls reproduction, but they were lacking of details and smoothness to produce a room impression. So the official tests never published any rating for reproduction of acoustical intruments or classic.

[@jenogilvie-grant2636]

Great video 👍very interesting 🤨

[@heywoodjablome5630]

I'm happy to re-home those speakers in Australia. Genuine offer. They'll get on well with Maggie 1.7s, yeah?

[@CarlVanDoren61]

Upgraded 1.7is to 20.7s skipped 3.7is

[@connorduke4619]

Beware the currency translation: $5000 USD is about $A20 million. So you might have to sell one or two of your smaller yachts for it.

[@bananasplitbrain476]

The design was soooo much better with the older prototypes....

[@yogimoninc]

Really interesting video, many thanks.

[@sudd3660]

woofer in a sealed box with dsp, some of the best solution i know of. there is less information on open baffle solutions and i have not heard one myself.

[@Roof_Pizza]

Yeah, it's best to control the driver as best as you can. Sealed and high current, high damping factor amps. Haven't heard a servo sub in person.

[@dlmp70]

Beolab 90 comes to mind

[@DodgyBrothersEngineering]

sudd do yourself a favour and listen to some open baffle bass, you will never want to go back to a box again.

[@BastianUllr]

@@DodgyBrothersEngineering ah… not necessarily. There is cancelation that makes for a cleaner bass as you’re effectively reducing the bass energy in the room. So, sure. You’ve done some “room treatment” as you play music by using a open baffle. And yes, it does sound clean AF. But also, you need very large woofers or many of them to make up for the required loudness. Second part of the story, how clean is the bass in the boxed speakers? Using all sealed and massively braced and well dampened boxes you get very very clean bass too. Yeah, you need more power, but it’s less space and it’s still free from boxy sound. In both counts I’ve perceived the same sort of result. Namely, music that sounds like no speaker is playing at all. One thing, open baffle is cheaper to pursuit compared to a very heavy large box. In a way open baffle requires more room, is very finicky with placement, and it’s more power efficient (if you keep the sensitivity of the midrange and chase up with large bass woofers) But if you can’t afford that much room to place speakers around, good boxed speakers (below 1% distortion @ target SPL) are very impressive on its own rights, no doubt at a costlier point, needing more power, but saving in space. Having listened to nice open baffle, I can sleep at night and enjoy music at day with a well built boxed design.

[@sudd3660]

@@DodgyBrothersEngineering would be nice with more experience with more box designs. for 200hz and below i like to run subwoofers, and 15hz output is needed. and no space for anything more than 20liter volume.

[@leonidassavalas745]

Paul, very interesting. If you have a second, I'm building Atmos 7.1.4 using Focal Alpha 80 EVOs. No sub yet. What do you, or anyone think? Keep 'em? Flush 'em?

[@hoobsgroove]

yes but depends on servo was it digital or analogue servo when you did your testing?

[@jked7463]

I keep saying that when you process sound, it is usually processes on the basis of sine waves. Much of music is not sign waves. Thwack of a drum stick on a rim, the initial attack of a hard piano hit on the keys, a distorted guitar, extremely complex audio of many sources overlaid on top of one another (50 person choir singing into a half a dozen mics with full orchestra with multiple mics) . In these instances processing tries to treat the non-sine wave sounds as sine waves destroying the immediacy of the sounds. Whenever I bring this up, I get people who are sure they know what they know telling me I am wrong. But 30 + years in the industry piecing my thoughts together tells me I am correct. Spear me full of holes all you want but it won't change my mind.

[@suenodistinto8464]

BONJOUR CHER MAGICIEN PAUL MERCI POUR CE MAGNIFIQUE TOUR DE MAGIE VIVEMENT LE PROCHAIN TOUR J'ARRIVE PLUS RETROUVÉ DES ENCEINTES QUI SONNE COMME MES IRS DELTA INFINITY QU'ELLE ENCEINTES ACTUELLEMENT POURRAIT ME RENDRE HEUREUX COMME MES IRS DELTA MERCI POUR TOUTES VOS VIDÉOS

[@tomehCanada]

REW makes it easy to do relative comparisons in distortion for woofer and sub woofer systems.

[@redellnapper8979]

Yes please let me know what's required to keep Annies legacy

[@rickbattle5706]

Great info, many thanks.

[@lonniefarmer7067]

Thanks!

[@johnbrentford5513]

I wish I could buy those speakers.

[@sickjohnson]

I suspect your A-B tested servo vs. "passive" had some DSP and time alignment in as well to beat the servo's cleanness Paul?

[@endrizo]

i like that big woofer at the sides, show them more..a detailed tour on these speakers , the midsize driver at the back is a passive radioator ??

[@GavinHodgson]

Great video!

[@murraywebster1228]

I’ll take them as studio monitors for my home setup….going cheap? 🤣😂🤣😂🤣😂

[@Mark-lq3sb]

Paul, Have you heard...? "Gee, Wally" R.I.P. Tony Dow

[@googoo-gjoob]

are you in Maryland? or, friend of CZEH

[@Mark-lq3sb]

@@googoo-gjoob Who the hell is CZEH? No, I'm not in Maryland. I just grew up watching the Beav!

[@googoo-gjoob]

@@Mark-lq3sb , i had just posted the same comment word for word on a local site.

[@googoo-gjoob]

1-29-18 means Jan 29, 2018

[@DodgyBrothersEngineering]

Makes sense that if you are limiting excursion to try and correct timing issues that it isn't going to have the same bass impact. You can have big bass, or you can have tight bass, but you cant have both due to physical limitations without a compromise somewhere.

[@sudd3660]

you could have a small sealed box with dsp, you get about anything out of that, with no discernable compromise.

[@DodgyBrothersEngineering]

@@sudd3660 lots and lots of compromise with that. Having run open baffle woofers for more than 10 years now, I can assure you that no boxed woofer can ever compete with open baffle. Not saying that open baffle doesn't have it's own challenges because it does, but DSP is just a band aid to make the driver do something it wasn't designed to do, and will alter the sound accordingly.

[@analogkid4557]

@@sudd3660 except for tons of distortion.

[@WoodstockG54]

Old age robs you of everything.

[@stimpy1226]

Isn’t there an audio museum that they could be donated to?

[@grumpy9478]

good point. why hasn't some billionaire audiophile w/ corporate / investment connections launched a foundation to create a proper Museum of Sound?

[@jasonkillsformomy]

And yet the best measuring subs on the market are not servo with the only exception being maybe Rythmik.

[@kpsr0461]

Nice speakers

[@tomthompson7400]

could you expand more on your definition of servo , a few examples or a diagram or two , my understanding of servo is along the Line 7 servodrives .

[@Ricky-cl5bu]

Ok 👍

[@paulzehner9419]

Is a servo speaker built differently, or do they use external electronics to control excursions such as an external bass computer?

[@gerritgovaerts8443]

Can someone explain me how anybody with a bit of knowledge of acoustics would design a tweeter array with approx 4 inches center to center distance when you can easily calculate that 2 adjacent tweeters will stop coupling after the wavelength is higher than the center to center distance , in this case definitely above 3400 Hz

[@gregmorris2022]

I’ll take ‘em

[@shadelizard]

Ok, I’m in. Paul can you figure out how to make a raffle so maybe one very lucky follower gets a chance to own those FR-30’s. I never win anything but just the chance….well that’s what dreams are made of ! That and maybe a lot of sleepless nights if you could make that happen.

[@mr.a5147]

Yuck

[@flavioc5389]

Any chance you guys at PS Audio will launch a new Sprout anytime soon? Thanks!

[@connorduke4619]

I so hope they call it the "Brussel" Sprout and paint it green.

[@jonathanbarrell82]

Ok fine. If I have to take them off your hands I'll do it for you. Please send them to Chch NZ. It's a hard thing being so generous but somebody has to do it.

[@neps4th]

1977/78; Servo -sub's amplifier on my Infinity Servo-stats always broke down. Paul, was that yours ?

[@Finn-McCool]

January 29, 2018 Ya NUMPTY NOODLE 😂

[@ellaochomogo5154]

I have been watching videos of Paul answering questions submitted by viewers and was wondering how to submit a question. Could anyone point me in the right direction? Thank you!

[@terrygesualdo9588]

Auction them I would love to have a Harvey Newdell design.

[@budgethometheaterandhifi]

Are those speakers for sale somewhere? I'd be interested to see what you're asking.

[@bwithrow011]

Paul, are these speakers 🔊 for sale or are they looking for a new home 🏡?

[@fadetoblack.-]

If the speaker is looking for a home why not my place?😁

[@geddylee501]

Which is the front of the speaker? Is it the black side or the curvy wooden side?

[@googoo-gjoob]

the black is the front

[@davej9228]

OK if you insist I'll take them of your hands. I'll even pay half shipping. Call me.

[@jagonzalez3061]

What means, servo-controlled Woofer?

[@googoo-gjoob]

google

[@bradwalker1259]

Sounds like your servos need some feed-foward.

[@MarcoRistuccia]

Is this concept the same as for the global feedback of an amplifier, and feedback systems in general? Meaning that feedback is good for correcting less than perfect stuff rather than for correcting stuff that has already a good non-feedback response? I think you've exposed this concept already. And the conclusion was that a bit of global feedback helps even a very good circuit that work with low distortion without it. Can't we apply the same concept to a well-designed woofer?

[@John-Edward]

I’m sure the FR30’s are great speakers, but I’m SO Disappointed they are Made in China…. 😢 I understand that Speaker contract MFG. pretty much doesn’t exist here in the USA, but I would like to have seen most of it outside of the ribbons made here! I know the woofers could have been as well as most of the parts for the stands and cabinets. I get that it would have probably cost about $5-$7,000 more, but that’s the development “Cream of the Crop” pricing. I’m so happy PS Audio does Assemble most of their wonderful products there in Boulder, CO USA!!! 😉😎

[@anthonymartino9917]

Mine do! Legacy Audio!

[@googoo-gjoob]

its ok with me if these beauties are a backdrop in e v e r y video

[@Projacked1]

Probably 2018....dude. LOL

[@dave2132]

I'll take them off your hands if your desperate.

[@NoEgg4u]

Paul, you have a printout from Dennis, of Clinton, Maryland, and yet you start your video off in a world of confusion. I am pointing it out because it is what you did, and it goes to why I wrote the below comments. Are you conveying to your viewers that this was the first time that you read Dennis' remarks? Are you conveying to your viewers that you did not print those pages -- that someone else printed them and handed them to you, just as you started recording? Or is all of this a theatrical performance? I am asking because why would you be confused over what you should have already read, and then start off your video with that confusion, and then post it to this public forum? You could have started your video again, without the confusion. So is this all a show? And to what end? You had a reason for starting off your video that way. Why? Because you started off your video that way. Ergo, you had a reason for doing so. What was you reason?

[@jasonkillsformomy]

His videos are getting more and more "comedic" for a lack of a better word. In almost every video he makes unnecessary comments about the letter and tries to be funny. If you compare to his behavior in videos made years ago the difference is not subtle.

[@bartkdt]

I volunteer to adopt your speakers. I promise a good home and to give them love for decades to come. Contact me for shipping info. Thank you P.S. I’ve safely kept, boxed in storage, a pair of Boston Acoustics A70 SII since 1990. Still like new. Because I love and respect them. Yes once I year they come out and still sound great great. Thanks Paul.

[@NoEgg4u]

@1:12 "Well, they weren't financial" -- referring to designing and selling the FR30s. Paul, you just make it hard to be taken seriously when you make wild statements like that. You are conveying that the countless hours that went into you and your team's efforts were done for exercise? For charity? You are conveying that you set their selling price to break even? A public service? You offered no reason as to why you and your team devoted countless hours in costs and materials, and it not be financially driven. So what are your viewers to conclude? @1:22 "I've been trying to find somebody, helping his son (Arnie's son), David, find somebody to take these speakers" Another wild statement. Maybe you have a Ferrari that no one will take? Paul, I believe 99% of what you say, when it comes to audio quality. But when you discuss other matters, you portray yourself as wandering in the dark, or even disingenuous. What gives?

[@MrCommunistGen]

In regards to the "financial" line, I understood it to mean that they didn't make any of their changes to save a dollar in engineering or material costs. In other words, I think he's implying no expense was spared. As for finding a home for the IRS killers, I'm assuming there's a "for the right price" implied, but he's intentionally trying to not be crass.

[@NoEgg4u]

@@MrCommunistGen I go with what was said, and not what was not said. And if he is worried about being crass, then why would he introduce the subject? Finding a home for those speakers had nothing to do with the guest's letter.

[@scottyo64]

@@NoEgg4u the IRS killers have a price, you must not watch all his videos.

[@NoEgg4u]

@@scottyo64 "the IRS killers have a price, you must not watch all his videos." What does that have to do with Paul's assertion that his basis for the FR30s was not financial?

[@BastianUllr]

@@NoEgg4u the meaning is that the reasons to develop a different design were not financial, as in, it was not a problem of money developing FR-30 vs IRS K. It was that the IRS K could be further improved. Pretty much his new designer shown Paul that he could instead chose to develop a better speaker. Why would he do that if not for financial reasons? Who is going to say that good sound is an investment for financial reasons to start with!! How’s that not a financial reasoning? If you can’t see that you could have a problem of neurodivergency, you could have a very interesting set of beliefs and I wouldn’t want to be your friend (cuz what friend is for financial reasons, or what ticket to go to a concert is for financial reasons) or I’m too stupid to understand this world and your are fine. But we are talking about a company here, so why Lexus launched the LFA if was not a financially viable project -. The same reason Pioneer launched the Exclusive 7 series in the late 80s. Do you think they made money out of that? Do you think that they hold any world wide reputation among the audiophile community due to that? No. Nor the LFA that Lexus launched changed how they are perceived. There is one thing though, the company might be viable in its own way. Statements sometimes are just a caprice of their engineers, developers, owners. They sometimes never thought to be able to use their time to do something they find wonderful themselves. Maybe he’s never going to see back the money and R&D those speakers commanded, maybe they’re never going to change the way PS audio is seen already. Focal would oversell their stupid Utopias over the FR-30 like nobodies business, just like Ferrari over sales Lexus every day of the year. Nonetheless, he’d die a proud man. He’d made money with his company. And he is still hoping and navigating a mad decision hoping it won’t break his company, for sure. But at the core, it isn’t a financially oriented decision. There is something else driving his pursuit. Companies have paid for it, like Sansui did for example. But if you think everything in this world is about how to make more and more money, PS Audio would be best suited trying to beat Sony or Yamaha. The revenue for sales of products from those guys will dwarf PS Audio as a whole. So, from the get go, I don’t even understand your bewilderment.

[@paulstubbs7678]

Too long?, 8 minutes is far from long.