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Harbeth Monitor 40 domestic specific

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  • Harbeth Monitor 40 domestic specific

    This thread specifically relates to the Monitor 40
    Alan A. Shaw
    Designer, owner
    Harbeth Audio UK

  • #2
    Pass Labs Amp With M40?

    Hi, I'm wondering if anyone has paired the M40 speaker with a Pass amp, such as the x250? Thanks

    Comment


    • #3
      I have been using x250 for M40 for a year. The combo sound very dynamic, without comparison, I was quite satifised with the combo. However, when comparing with other Harbeth setup, I found Pass amp lack of some fineness and high range sweetness.

      So I changed to MBL 8011S amp, MBL doesn't sound as dynamic and impactful as Pass. But I would say MBL has even better microdyanmics. MBL sounds fineness, sweetness, detail without being aggressive, most important give me back Harbeth's musicality. Pass sounds like a good hifi while MBL sounds more like live music. I'm so happy with the move.

      Comment


      • #4
        M40 - Love at first listen, and second and third.



        The first rule of audio, I learned when I was a boy, was ?Your money is best spent on the speakers.?

        My friends and I had apparently decided that this rule was irrelevant. We bought our speakers, and then proceeded to spend thousands on cables, phono cartridges, vibration isolators, silver, gold, ointments, sprays, strange devices and packaged placebos to squeeze less than a few percent improvement in audio quality. In fact, we seemed to be feeding an industry of wonder products (we wondered if we could hear a difference). I spent sessions listening to expensive cables, tubes, connectors and other stuff, during which we argued about whether they actually improved the sound at all. Contrast that with our first listen to the M40, which was so overwhelming it could be measured on the Richter scale!

        I listened to the M40 at www.audioconnect.com in New Jersey. We brought boxes of music CDs and our own tube pre-amp and 50 watt tube amp to see if it could drive the M40.

        We pumped 50 watts through the M40, and the excellent quality knocked us off our chairs. You can find plenty of detailed descriptions of what the M40 sounds like. To say we liked what we heard would be an understatement. In my case, the 50 watt tube amp sounded outstanding up to ? volume (far beyond my listening levels -- I rarely go beyond 75 DB when listening). We listened to all the music we brought. The demo lasted hours. I wanted the speakers. But some dim memory told me not to propose marriage while hormones are in control.

        I came back with another box of CDs. This time I listened on the store?s solid state pre-amp and amp, with many watts of power. To my ear, my tube pre-amp and amp sounded better than the solid state setup, but I like my tube sound. Of course it was the M40 that let me hear the difference. At this point it was raw lust for the M40s.

        I heard none of the problem bass some people chatter about on the net. I had to fix problems with high frequencies on other speakers in my listening room. If I had to make some changes to correct my room for bass, I was OK with that. I just liked what I was hearing. From what I heard, there were no problems ? none. John made me an offer I could not refuse and my order was placed with a handshake.

        My main problem while I was waiting for delivery was every other speaker I listened to after the M40 suddenly sounded small and boxy. The demo had spoiled me.

        It took nine and a half long weeks to receive my M40s. I was worried they would not sound as good in my home as they did in the demo room (a common complaint). It turned out that in my home they sounded just as good as or better than the demo. A few tweaks in positioning and height put the bass where I like it. The tweeter was such an improvement that I was able to remove some of the high frequency room treatments. No further room modifications were needed, other than rearranging some room treatment panels.

        There is indeed a thick sound curtain. I can listen with the volume lower since the big size produces higher volume. I am hearing loads of details that other speakers I have owned did not reproduce. In some cases, I?m even hearing instruments I did not know were there before.

        The M40 has the power and authority to present the orchestra. It leaves me satisfied where other speakers left me yearning for more bass and less highs. The sound does not get congested or overwhelmed by the constrictions of a small box. These speakers are not a fashion statement, but they truly are ?the best seat in the house.?

        Of course, speaker selection is made on personal preference. I have owned and listened to a lot of speakers, electrostatics, boomy shrill towers and lots more. I had wondered if somehow other makers had figured out how to get small cabinets with two 6-inch woofers to sound like a 12-inch woofer. Of course, they can?t, any more than bongo drums can be added together to equal a bass drum. Much of what I am hearing from other speaker makers is attention-grabbing tweeters that jump out at me and then make my ears hurt and ring after a while. Apparently marketing has entered a new dimension where hot air is confused with solid substance?.

        The M40 filled my needs better than other speakers I have heard in this price range and more. They agree with my musical taste and finances. I tip my hat (and wallet) to Harbeth for sticking to what works. As a bonus, the M40 also freed the potential of my pre-amp and amp, allowing them to deliver additional quality I did not know they possessed. It is rare to have so many happy surprises in audio.

        Two of us went to the demo and both of us ordered the M40. This is clearly the most satisfying audio purchase I have made. It was also my biggest investment. They cost double what I paid for the SHL5, but they provided me a return on investment (enjoyment) that justifies the cost. You could not possibly ignore the sonic improvement if you wanted to. It is so evident, I?m unclear now how I was ever tempted to waste time and money on other high-priced accessory crap.

        The M40 has made a good first impression on me and that has lasted. I am happy I woke up from the marketing fog and remembered the first rule of audio I learned: ?Your money is best spent on the speakers.?

        Comment


        • #5
          6-year old model 40s

          What are the differences between a new Model 40 and a 6-year old pro version model 40?

          Are they essentially the same?

          I see that one's industrial paint finish, the other real wood. And the pro version has speakon connectors, but I'm not familiar with those........

          Did they use Radial drivers back in 1999 when R Greene did his review?

          Comment


          • #6
            M40 Stands

            A pair of Sound Anchor Stands arrived for the M40’s. They sound great compared to the stands I was using. I found 18 inches (45.72 cm) to be the correct stand height for my room. At a lower height they produce less detail and more bass, higher and they produce less bass.

            Photo of old stand (Lovan 18" on left) next to new stand 18" Sound Anchor on right)
            http://www.s91519931.onlinehome.us/soundanchor1.jpg

            Each stand weights 80 pounds (36.28 kg)! I had a real work out while moving the stand and the speakers. They are very solid and I lost all fear of the speakers falling with this stand. The top frame of the stand that the speakers rest on are solid steel bars, not tubing. The vertical struts are tubes that are filled with damping material. The bottom “H” section are solid ingots of steel. The stand is completely dead when you tap it. If you like SOLID construction and mass, this is it! They perform well and improved my sound. They should last several life times.

            Once I sank the spikes through the carpet into the wood floor – the sound really came alive. I thought these speakers had given me all they had to offer since they arrived but I was wrong. The stands improved the sound noticeably on bass detail.

            The Sorbothane blue dots that came with the stands are supporting the speakers on the stands. I have not had a chance to test other means of supporting them on the stand. Recommendations that don’t damage the cabinet are welcome.




            Comment


            • #7
              Re: M40 - Love at first listen, and second and third.

              And what about money spent for cdplayer and amp?

              David


              Originally posted by TNIC


              The first rule of audio, I learned when I was a boy, was ?Your money is best spent on the speakers.?

              My friends and I had apparently decided that this rule was irrelevant. We bought our speakers, and then proceeded to spend thousands on cables, phono cartridges, vibration isolators, silver, gold, ointments, sprays, strange devices and packaged placebos to squeeze less than a few percent improvement in audio quality. In fact, we seemed to be feeding an industry of wonder products (we wondered if we could hear a difference). I spent sessions listening to expensive cables, tubes, connectors and other stuff, during which we argued about whether they actually improved the sound at all. Contrast that with our first listen to the M40, which was so overwhelming it could be measured on the Richter scale!

              I listened to the M40 at www.audioconnect.com in New Jersey. We brought boxes of music CDs and our own tube pre-amp and 50 watt tube amp to see if it could drive the M40.

              We pumped 50 watts through the M40, and the excellent quality knocked us off our chairs. You can find plenty of detailed descriptions of what the M40 sounds like. To say we liked what we heard would be an understatement. In my case, the 50 watt tube amp sounded outstanding up to ? volume (far beyond my listening levels -- I rarely go beyond 75 DB when listening). We listened to all the music we brought. The demo lasted hours. I wanted the speakers. But some dim memory told me not to propose marriage while hormones are in control.

              I came back with another box of CDs. This time I listened on the store?s solid state pre-amp and amp, with many watts of power. To my ear, my tube pre-amp and amp sounded better than the solid state setup, but I like my tube sound. Of course it was the M40 that let me hear the difference. At this point it was raw lust for the M40s.

              I heard none of the problem bass some people chatter about on the net. I had to fix problems with high frequencies on other speakers in my listening room. If I had to make some changes to correct my room for bass, I was OK with that. I just liked what I was hearing. From what I heard, there were no problems ? none. John made me an offer I could not refuse and my order was placed with a handshake.

              My main problem while I was waiting for delivery was every other speaker I listened to after the M40 suddenly sounded small and boxy. The demo had spoiled me.

              It took nine and a half long weeks to receive my M40s. I was worried they would not sound as good in my home as they did in the demo room (a common complaint). It turned out that in my home they sounded just as good as or better than the demo. A few tweaks in positioning and height put the bass where I like it. The tweeter was such an improvement that I was able to remove some of the high frequency room treatments. No further room modifications were needed, other than rearranging some room treatment panels.

              There is indeed a thick sound curtain. I can listen with the volume lower since the big size produces higher volume. I am hearing loads of details that other speakers I have owned did not reproduce. In some cases, I?m even hearing instruments I did not know were there before.

              The M40 has the power and authority to present the orchestra. It leaves me satisfied where other speakers left me yearning for more bass and less highs. The sound does not get congested or overwhelmed by the constrictions of a small box. These speakers are not a fashion statement, but they truly are ?the best seat in the house.?

              Of course, speaker selection is made on personal preference. I have owned and listened to a lot of speakers, electrostatics, boomy shrill towers and lots more. I had wondered if somehow other makers had figured out how to get small cabinets with two 6-inch woofers to sound like a 12-inch woofer. Of course, they can?t, any more than bongo drums can be added together to equal a bass drum. Much of what I am hearing from other speaker makers is attention-grabbing tweeters that jump out at me and then make my ears hurt and ring after a while. Apparently marketing has entered a new dimension where hot air is confused with solid substance?.

              The M40 filled my needs better than other speakers I have heard in this price range and more. They agree with my musical taste and finances. I tip my hat (and wallet) to Harbeth for sticking to what works. As a bonus, the M40 also freed the potential of my pre-amp and amp, allowing them to deliver additional quality I did not know they possessed. It is rare to have so many happy surprises in audio.

              Two of us went to the demo and both of us ordered the M40. This is clearly the most satisfying audio purchase I have made. It was also my biggest investment. They cost double what I paid for the SHL5, but they provided me a return on investment (enjoyment) that justifies the cost. You could not possibly ignore the sonic improvement if you wanted to. It is so evident, I?m unclear now how I was ever tempted to waste time and money on other high-priced accessory crap.

              The M40 has made a good first impression on me and that has lasted. I am happy I woke up from the marketing fog and remembered the first rule of audio I learned: ?Your money is best spent on the speakers.?

              Comment


              • #8
                Re: M40 - Love at first listen, and second and third.

                Originally posted by airdavid
                And what about money spent for cdplayer and amp?

                David
                My short answer is - Try before you buy.

                With some analisys funds can be applied to produce the best sound for your budget. I believe I can obtain better sound with $10,000 speakers and a $100 amp than I can with a $10,000 amp and $100 speakers. I may succeed in getting better sound, but in both cases I would be wasting the potential of the better component.

                I would be willing to challenge you that I can improve your system sound a great deal more with $1,000 of room treatments than you could with $5,000 of cables. I would be willing to modify the challenge to $10,000 of cables vs the magnitudes of gains you would get buying the M40 and using inexpensive copper cable on the entire system.

                Building my system was all about similar decisions. Each time I remove a limiting component the sound improves to the level of the next limiting component. Ideally all components would be up to the same sound reproduction quality. That would provide the perfect return on the investment. A little planning is needed to avoid mismatches.

                To try and extract maximum value from my purchases, my first order of funding priorities might be as follows (but not necessarily the order of purchases).

                Room treatments – critical path component REG’s articles are required reading www.regonaudio.com
                Speakers – The interface to your ears - the ultimate limiter in sound quality
                Pre amp – equal to speakers quality. This one is perfect for the M40 http://groups.yahoo.com/group/alaapaudio/
                Amp – ideally needs to match quality of speakers and pre amp
                Amp and pre amp internals – capacitors and tubes
                Financial advisor
                Marriage counselor

                CD/turntable tone arm, cartridge etc.
                Divorce lawyer

                I was at an audio show this Sunday. I always get the jitters at these things because I am worried I might hear something that sounds better than my system at a similar price point.

                My jitters were for nothing. I was again reminded there is no relationship between price and value.

                I listened to about 20 systems. Some systems costing 3 times the price of my system and speakers that cost well over twice the price of the M40. None sounded as good as the M40 overall. Some of these gargantuan, status symbol/art objects sound like they were designed by an interior decorator. It seems form has priority over performance.

                In a single cabinet one enormous monolith had several side firing woofers (both active and passive), 3 front fire mids and a number of rear fire tweeters. Others had several rear fire woofers. The bass sounded better when you walked behind the speaker than when in front of the speaker in the listening position! A few exhibiters had their speakers jammed in the corner of the room but still produced little bass. All but 3 systems were too high frequency heavy. After a while you begin to think if you are not hearing shrill, something must be missing. But they were very pretty and you could order them in a variety of colors. (I would be happy to send you a link to the photos of all the stuff that does not sound as good as the M40) Those expensive monsters would be a nightmare for my listening room.

                Out of 20 exhibitors 85% sounded worse and 15% (3 exhibitors) came close to sounding as good as the M40, but not equal the M40 overall. Those 3 speakers cost double and triple the price of the M40. As you may have guessed I hold the M40 in high regard, and the more comparisons I do the higher my regard.

                Comment


                • #9
                  Re: Harbeth Monitor 40 domestic specific

                  TNIC: How would you characterize the sonic differences between the Super HL5 (which I own) and the Monitor 40 (which I have never heard)?

                  Thanks.
                  -Dan

                  Comment


                  • #10
                    Re: Harbeth Monitor 40 domestic specific

                    Originally posted by danrubin
                    TNIC: How would you characterize the sonic differences between the Super HL5 (which I own) and the Monitor 40 (which I have never heard)?

                    Thanks.
                    -Dan
                    Are you wondering if the SHL5 performs like the M40 or are you thinking about acquiring an M40 and want to know if it is worth the difference? Or some other reason?

                    Both speakers are top performers in their tiers. We would be comparing 2 different tiers and speakers designed for 2 different purposes. That is not valid criteria for a comparison. I ride bicycles and would not compare my mountain bike with my road bike even though both are at the top of their tier.

                    The Bob Neill does some comparisons in his review of the M30
                    http://www.enjoythemusic.com/magazin.../harbeth30.htm


                    The SHL5 sets a high standard and shares some commonality with the flagship. But to put it bluntly, At twice the price, and twice the size, the M40 does everything the SHL5 does much better, and it performs better because of many other factors in addition to size. And I doubt we would expect or accept anything less. Does that put the SHL5 in bad odor? Defiantly not. All the speakers in the line have their purpose. Thank goodness we have choices. Unfortunately I don’t have the room or money to put the M40 in every room in the home. But I do have other choices in the production line.

                    The majority of audiophiles I meet seem to be searching for better sound for two reasons.
                    1) They are dissatisfied, often bitter, with what they purchased and are hearing and want to correct that.
                    2) They like what they are hearing and want more of it.

                    I bought the SHL5 because I like the sound. In fact I liked the sound so much I started craving as much of that goodness as I could possibly get. So a great big double dose of the Harbeth sound was exactly what I was searching for. The M40 delivered it. Finding true satisfaction in audio is rare. I was/am very happy I found it. The M40 pleasure does not fade as it does with so many other purchases. My friend describes the M40 as “British polite with balls”.

                    If you are still feel the need for specific comparisons you can contact me via email to set up a phone call where we can have a dialog. I love discussing audio. We could cover more in 10 minutes on the phone than we could with 3 months of writing I suggest the phone for expediency not to hide lurking dissatisfaction.

                    The M40 is referred to as the flagship of the Harbeth line. Webster’s definition of the flagship is - "the finest, largest, or most important one of a series". I suspect Webster is an M40 owner.

                    TNic

                    Comment


                    • #11
                      Harbeth Monitor 40 (domestic) - LS5/8 history ....

                      Originally posted by TNIC
                      ... We would be comparing 2 different tiers and speakers designed for 2 different purposes. That is not valid criteria for a comparison.
                      Please remember that the intentions, application and primary users of these two speakers are very different. The SHL5 is the 6th generation of the original Harbeth HL Monitor (launched in 1977) which was quickly taken-up by domestic customers as an excellent all-rounder, equally at home in the studio or house.

                      What was specifically in my mind, and on my agenda when designing the M40 was a replacement - literally a drop-in replacement as I have said before - for the BBC LS5/8. I'd always had a curiosity about the 5/8, since it was a large and imposing box, rather untypical of the width/height proportions of the BBC legacy speakers, and with only two drive units when its (Harwood designed) predecessor, the LS5/5 was a three way system. The LS5/5's development story was written up and published in Wireless World, a consumer magazine, over three months in the late 1960's - and I had scrutinised those articles in great detail over the years. In fact, they alone fixed my fascination and curiosity with loudspeakers 'in the BBC way of doing things'.

                      So, the lingering question in my mind was (and to some extent still is) 'why, when Harwood laid out so clearly in the public domain the reason for making the LS5/5 a three way, was all that thinking reversed or ignored - what could the possible justification be for making the 5/8 a big, fat two way?'. Fortunately, the BBC's Equipment Disposal Department had a pair or 5/8's available for purchase, I bought them, and brought them back to Harbeth for a thorough acoustic, electrical and mechanical evaluation. To say I was surprised is an understatement. The bass output was astonishingly powerful, as indeed was the sensitivity due to the active electronics and the huge magnet on the bass unit.

                      But, the measured frequency response, with its sucked-out middle and jacked-up top looked very odd; totally different to that glorious specimen written about in the BBC's own Design Report. So odd that I made contact with Harwood, prepared as much evidence as I could, and visited him at home with both my measurement curves and the BBC's Design Report, which in fact he had and which shows the frequency response as basically a flat line. Harwood's comments transcribed by my secretary were that after studying my photographs and curves he said ".... what you have here is not the speaker I was involved in prototyping. I barely recognise it". He further commented, with incredulity, that 'the diffraction slot and narrower baffle both aided the dispersion of the 12" woofer off-axis in the midband/upper midband ... to deliberately widen the baffle and remove the diffraction slot seemed highly counter-intuitive ....'.

                      In other words, someone involved at production engineering stage in the design process (presumably in the BBC) had, according to Harwood, made significant adjustments to not only the prototype cabinets as he had them when he retired from the BBC but also to the overall shape of the frequency response, attributed to components in the bass/mid filters within the Quad amps. Maybe his memory was playing tricks on him regarding the cabinet proportions, but the frequency response differences were a matter of measurement, and fact.

                      Concerning the overall response shape - dished in the middle - this was am enigma and I spent many hours chasing clues and contacts in the BBC. Eventually I made contact with a design engineer on the periphery of the 5/8 design who, upon investigation, agreed with my conclusion that a mistake was made in the transposition of circuit components from the master prototype to the production models and/or the characteristics of the 12" bass/mid driver had significantly altered as production commenced - and this was not taken into account by reworking the baffle-step correction circuit. Hence, this circuit which over-compensates, and sucks out the middle. Either way we will never know: in a large organisation policy right or wrong very quickly becomes established and is not questioned, just duplicated.

                      Whilst the 5/8 with its relaxed, distant midband is not especially unpleasant to listen to, its midband colouration is high, certainly by the standards of any RADIAL Harbeth and the briefest side by side comparison of a real voice on the M40 v. 5/8 would leave you in not the slightest doubt: whilst the chest and top of the voice on the 5/8 are credible, the articulation in the midband is not natural. I was (and am) so confident that this can be demonstrated with ease that several years ago when launching the M40 I gave a demonstration of the M40 side by side the 5/8 to no less than the Institute of Broadcast Sound, using my own voice, pre-recorded. You would not take on such a challenge unless you were very confident of your facts. I was, and I am. This was written-up in the IBS's Journal at the time.

                      From an entirely pragmatic marketing position I knew that if a BBC user had seen 5/8's at the corner of his vision for twenty years or more then to change the aspect ratio would be unwelcome, so that fixed the shape/size. I reversed the curious 5/8 decision to make the M40 a three way (just like the 5/5) and reset the basic frequency response as a flat line, adopting the 5/8's tailored response at the bottom end. This means that, just like the 5/8, the M40 is designed to be used in well-lagged environments where the walls and floor can absorb the considerable LF output. Avoid at all costs sprung floors, hard tiled floors or basements/garages underneath - the M40 was not designed to work in those spaces. It is a thoroughbred studio monitor.

                      As we have operated a trade-in scheme with the BBC for several years (new-for-old, helps with their WEEE disposal problems) we have taken-in many 5/8's directly from working studios as complete kits with the modified Quad amps and replaced them with Monitor 40s. I believe that we know more about these speakers than anyone outside the BBC - and possibly inside. Almost certainly Harbeth has the largest collection of 5/8's outside the BBC anywhere in the world. We have measured them and can report with certainty that accurate pairing of them is not possible (a long-time complaint in the BBC) and that the shape of the dish in the midband frequency response is variable - by several dB's across theoretically matched specimens - which has the hallmark of a manufacturer struggling to retain QC over a design or component parts that are inherently variable, and may well age rather badly.

                      The M40 solved all these problems at a stroke, and when you consider that much or even most BBC originated Radio drama (let alone a substantial amount of BBC-produced TV) is made on M40's I think we can confidently say that the 40's are truly an upgrade in keeping with the BBC's traditions and accepted as just that.

                      Although the 5/8 was not perfect by any means, its colourations are realtively low-Q and hence benign and tolerable if you sit at the sweet spot. Whilst it left the listener clutching for a midband clarity (on voice) that was not to be had, it was not markedly fatiguing. This was probably the consequence of the rather gentle crossover filters plus the big, soft polypropylene 12" unit which in itself introduced off-axis problems. I could live with the 5/8 - although I'd be missing a great deal of detail in the music - but I could never, ever live with certain other speakers that have found their way into broadcast monitoring and are exceedingly fatiguing. Impressive though on first listening: but after an hour ......

                      I hope that this all helps explain the position. This has taken me down memory lane again.
                      Alan A. Shaw
                      Designer, owner
                      Harbeth Audio UK

                      Comment


                      • #12
                        Re: Harbeth Monitor 40 domestic specific

                        what a great story from Alan.

                        thx.

                        Comment


                        • #13
                          Re: Harbeth Monitor 40 domestic specific

                          I thank you very much for your kind thought. It took a long time to pull it together, after checking my notes etc.. Thanks again.
                          Alan A. Shaw
                          Designer, owner
                          Harbeth Audio UK

                          Comment


                          • #14
                            Measuring frequency response of the M40 domestic

                            I've been following some of AS posts on measurement with interest. I have tried three ways of measuring the in-room response of my M40s (1st generation model with the ports at the bottom and the bass driver with a slot).

                            1. Option 1: Use the infamous Radio Shack meter with the "C" weighted position, and use the 1khz - 20 hz warble tones in the Stereophile test CD.

                            2. Option 2: Use a RTA frequency analyzer provided by the Behringer 2496 Ultracurve, with the ECM 8000 RTA measurement mike.

                            3. Option 3: Use the sweep tone provided by the Velodyne DD-12 subwoofer connected to the ECM 8000 (the Velodyne has a video output that shows the sweep tone output).

                            As you would imagine, the three approaches give different results. Option 1 shows the most irregular response (fairly high peaks at 60, 100 ,160 -- classic room mode effects).

                            Option 2 (the pink noise test) gives a much smoother response, still elevated in the bass, but smoothly decreasing from the bass to the treble. It is actually quite instructive to measure the M40 about a meter out -- the flatness of response is quite remarkable.

                            Option3 (the Velodyne swept tone) gives the smoothest response, but only measures from 20-200 Hz. The response fluctuates a lot depending on where the mike is placed, and it is fun to see the wild swings in real time as you move the mike around.

                            Which approach is to be trusted the most? I should add to no one's surprise that despite all the frequency response deviations (real or not), the M40s make wonderful music.

                            - Sridhar

                            P.S. My room is quite large (30' long, 17' wide, with a high ceiling of around 14' which is sloped from 10' near the walls). Standard furnishings -- carpeted floor, two sofas and two chairs, no other room treatments.

                            Comment


                            • #15
                              Re: Measuring frequency response of the M40 domestic

                              I would guess that Options 2 and 3 are the better measurements. How much different are they from one another in the 20-200 Hz range?

                              Do you use the Velodyne with the M40s? How well do they work together?

                              Comment

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