maxg

Thanks - more steps backwards. OK - more complex - no simple calculations. I get it. Input appreciated all the same.

Robert, I think we are now partners according to Mas. I used to have cohorts but I have moved on since then apparently. Am I in a fight? Nothing much coming from the other side other than snide remarks and pomposity. I haven't worked up a sweat yet.....[] Mas, This is a thread titled "How your room impacts how you hear sound" If ever there was a thread offering an opportunity for you to share your knowledge this was it. An opportunity missed for reasons unknown. One can only assume that your knowledge stops at the smattering of technical terms you have picked up and the arrogant, holier than thou attitude which impresses no-one.

What is this ridiculous generalization you keep trying to make about "crappy components"? You and one or two others are the only ones that seem so preoccupied with this nomenclature. This emotional preoccupation that you have with 'crappy' components is amazing. But since you are preoccupied with it and continue to look for silly and simplistic generalizations, and then complain that we do not explain your cartoon conception of a sound system adequately is your hangup. And what is even more humorous is that you care about trying to make absolute judgments based upon vague generalizations and ill defined terms. And then you try to debate issues on your interpretation of them. And yet despite my all to obvious limitations I still managed to assemble a decent sounding system in my room - go figure! FWIW crappy components was lifted from crappy room in the original post - it isnt my decription - I borrowed it. Try this then: Bose cubes - brilliant room Vs KHorns - average room.

Thanks for that - you just made things even more complicated - just when I thought I was getting somewhere. However - doesn't the cross-over serve to equalize the loads the amp sees between the different drivers enabling us to treat the speaker as a single unit when assessing senstiviity? If my original question was not clear (taking the KHorn Type A X-over as my example): We see a figure quoted for sensitivity as 104 dB/w/m with no mention of impedance. I am assuming that this measure is at impedance of 8 ohms - as most measures are. What confused me is that to hold this constant level (104 dB) - taking into account impedance variations across the frequency spectrum appears to vary the power need by a factor of 10 (assuming voltage to be constant). Is this correct? Does voltage actually vary? Are my calculations wrong somewhere?

Shawn, "I would agree. Decent components (amps/preamps/sources) in an outstanding room will trump outstanding components in a crappy room." Not exactly 2 sides of the coin is it: "Decent components (amps/preamps/sources) in an outstanding room will trump outstanding components in a decent room?" "Crappy components (amps/preamps/sources) in an outstanding room will trump outstanding components in a crappy room?" Neither case seems quite as clear cut now.

"But your speakers do matter." Why?

What is tiresome is the continuous erroneous assumptions of those who have misrepresented the acoustic treatment process from the beginning, and failing to understand it construct scenarios that are flawed in their basic conception. First of all, room treatments are not used in lieu of your systems volume controls! You might want to start by going back and reading some of the posts already made on the subject. You will find that none of them assume your continued 'equipment centric' point of view. Some equipment will effect the interaction of the sound and the room, but that is primarily in the form of speakers. Likewise, signal alignment can have an effect. But we really don't care what amp you use. Nor if its tube or SS. Nor if you like TT or CDs. The purpose of acoustical room treatments are not to make your amp sound better. It is to remove the detrimental effects of various acoustical phenomena so that you can better hear whatever is coming out of the system more accurately. You folks may focus on EQ and other manners of 'shaping the source', be we are not concerned with that except to remove acoustic anomalies from the sound field. If your equipment stinks, it will do so because of its own merits. If it sounds good it will do so because of its own merits. That's a "Yes" then is it? Remarkable.

Mas, You are a master of the non-helpful post. Probably a great reply - but unintelligible - try not to assume any of us are up on the latest acoustical research and explain things in layman's terrms so people like me can get it. Now: Let us assume I have a B&W 802 speaker and am driving (?) them with a 300 B SET amp - all 8 watts of the beast. Nice mids and highs but rather limited bass. I swap my 300B for a Yamaha MX-D1 500 wpc digital monster. I now have bass to burn but my room is reverberating - the windows rattle and the Tsatski's (alternative spelling from Mark's post above) keep falling of the mantelpiece. Are you saying the room treatments would be the same in each case? For a simpleton like me it would appear bass traps in the corners might control the bass output from the 500 watter - a bit, but with the 300 B it would probably not make a whole lot of difference.......

"But a "properly functioning" amp, pre-amp, cables, have IMO and experiance have less of an impact on the sound one hears than the room." Not to pick this statement apart (in other words - to pick this statement apart) had you said "properly matched" as opposed to "properly functioning" then I would agree with you. Of course - getting to properly matched is the journey we are all on - and it is not limited to the amps pre-amps and cables. All of this raises another question - when is the right time to address room issues? If I have a system and treat the room to make that system sound good in there do I need to re-treat the room is I change something? Paraphrasing the example that Shawn made several pages ago - an amp that is weak in bass when matched with a given pair of speakers might need very different treatments from an amp that is strong in the bass. If you treat the room for one - all of that work might have to be undone or redone with the new amp. Aside from that the one big advantage of investing in equipment over investing in room treatments is that equipment is more likely to be transferable should you move house - or room within the house. Just thoughts.....

Sure I am. I was just playing off your "cat in the box" routine. You guys are tossing theoreticals out there that, while they muddy the waters, are insignificant IMO and until you can demonstrate through objective performance data those electrical signals do change and change significantly, I simply view them as "cat in the box" mental masturbation. I would still recommend a JM preamp or VRD's regardless of whether they were in a closet, bathroom, or living room. Klipschorns might not be the best choice for a closet however or a sun room or a bathroom. I enjoy your logical exercises Max and enjoy the contrarian stance you like to take. PS. It was cohort not consort. :^) I doubt your wife will mind... although you do live in Greece. [] PSS. Yes, pauln, I will. Electrical signals change due to rooms? No, the title of the thread is how the room impacts how we hear sound. Not how does a room impact an electrical component. I am not sure how you listen to music, but I believe 99.99% listen to it via sound waves that travel through the air. Those waves interact with the room they are in. You are too early in the process. Jackson, My fault - I semi hijacked your thread chasing a rabbit called back emf that implies that room:system interface is 2 way. and that actually the electrical signals coming from the amp would indeed change. It is probably a nebulous concept so I will park it here.

In a recent thread Mark mentioned, laughingly, how amp manufacturers boast that their amp doubles in power going from 8 ohms to 4 ohms but never mention what happens when the impedance climbs to 16 or 32 ohms. This got me thinking and then confused the hell out of me. As follows: Lets take a Khorn with a type A crossover. I have seen that the impedance of this speaker varies quite dramatically: 5.5 KHz - 3.5 ohms 35 Hz - 15 ohms 2 KHz - 40 ohms All approximate values. Now - let us imagine we are playing a frequency sweep at 104 dB (nominally stated to be 1 watt of power using 104 dB/w/m) I had thought that amps hold constant voltage and it is the current that goes up (and the power). Now this doesnt make sense according to my calculations: If we suppose the 104 dB figure is into an 8 ohm load when needing 1 watt: Power = Amps squared * Impedance If the impedance is 8 then amperes = root (1/8) = 0.35 amps (approx) Voltage, therefore (Power = volts * amps) = 2.85 Volts So far so good: That figure looks quite familiar. Now - if we take the impedance at 3.5 ohms and the voltage is constant: Power = V squared / Resistance = 8.12 / 3.5 = 2.3 Watts (amperes have climbed to 0.8 A) On the other hand, at 40 ohms power is a measely 8.12/40 = 0.203 watts (amperes have fallen to 0.07 A) So I am holding a constant 104 dB and my power requirements are varying by 10 fold? Huh? Where did I go wrong?

"I simply view them as "cat in the box" mental masturbation. I would still recommend a JM preamp or VRD's regardless of whether they were in a closet, bathroom, or living room. Klipschorns might not be the best choice for a closet however or a sun room or a bathroom." I think I did too when I originally posted it - now I am not so sure. I have always assumed, as you have done on here that in any given room the source (being the whole system from source to speaker in this case) is constant from room to room and that only the accoustics change the result within the listening room. I now think this goes a step further in that the room is probably affecting the actual sonic output from the devices themselves. What the last few pages of this discussion has highlighted it that there is no way to tell. This is interesting to me as it is something I have never considered. It appears that the interaction between room and speaker may indeed be a 2 way process - each is affecting the other. Certainly the interaction between room and source is 2 way when dealing with vinyl. I recall a friend's system that was running a TT and a CD player with a pair of B&W 802's in a smaller room. When playing the CD there was no problem. When playing with the TT however the woofers on the speakers vibrated wildly as soon as the volume started to climb - to the point that he actually burned the woofers and had to replace them. Playing the same system with a pair of B&W CDM1's the woofers behaved perfectly. We surmised after some time and a lot of play that the woofers on the 802's were loading the room so heavily with base that the cartridge was picking up the vibration and running it back through the system in what seemed to be an escalating loop. What we had not considered is that back EMF from the speakers (caused by reflections from the room back onto the surface of the woofers) might also have been exacerbating the problem. Is any of this important - don't know - might be mental masturbation - might not be. MAS has been beating the drum of the importance of the speaker/room interaction for some time. If this is indeed a 2 way process as it appears it may well be then it just could be that it is even more important that he realized (unless he already knew all of this). I dont have the answers - I am not even sure I have the questions yet but I am trying to figure this out on a logical level rather than a math / physics basis as I lack the knowledge to do it that way. Does any of this affect our ability to recommend components for use in a system? To a small extent I would say yes at this point. As you yourself say "Klipschorns might not be the best choice for a closet however or a sun room or a bathroom." We already knew this - we just might have stumbled on a bit more of the reason why.

Shawn, Huge DG fan - well spotted and wouldnt a babel fish be useful around here at times - or maybe not. Merkin, This thread is a bit confusing now - let me help out a little: You dont put piles of insulation, plants, wet clothes and blankets in your corners - you spread them around the room. Heavy curtains will be fine for the french windows. If you put dry towels in front of the shower with the shower door open you get free wet towels and keep the floor dry. Its all so easy when you know how.....[]

There is no comparison.

Dave, TBHWY? To be honest with you - just figured it out whilst completing the text below. Anyway - sorry I appear to be bustin your chops over this - I will stop. I think the cause of this apparent disbelief is that audio memory - in the sense we are using it here - it notoriously poor and largely cited as the reason DBT's are so often failed with component swaps. If you genuinely to have total sonic recall it is a truely rare gift. I certainly do not - I can recall aspects of a system's playback but not more. Case in point. Last week I was at a house listening to a high end system. Last night I listened to the same music on my own system. It sounded FANTASTIC last night - but was it better or worse than Friday's session - can't tell - cannot remember Fridays performance in enough detail. In fact tonight a few audiophiles are coming over to give their opinion - and tomorrow night come to that - but SWMBO and Junior are away so I can.....

Sorry Robert - I will leave that one for another day perhaps. Shawn, Good point - forgot that one. Gets worse still if you are listening to vinyl where the cartrdige could be picking all this mess up and feeding it back into the signal - so even the signal from the vinyl is not the same - so Jacksonbart was right all along and Robert just diappeared in a puff of logic. For my next trick.....

Happy birthday plus 3 Gary. So .......what did you do to celebrate?

Robert, At the risk of getting seriously off topic (sorry all) read up on Schroedingers cat. The basis of it is that there is a cat in a box with a loaded gun. At some point the cat will cause the gun to go off and kill the cat. Schroedingers point was that until you open the box to examine whether or not the cat has killed itself it is neither dead nor alive. Its state is determined by the observer. In our discussion (almost back) the recorder is, in effect the observer - but only once someone listens to the tape. Till then the tree made no sound. For the loud speaker we are not measuring the electical signal in order to assess the sound it is producing - we can only measure the sound the speaker is making - and that is in the room - which negates the measurement. To be fair we could set up a system to measure the excursion of the drivers in the speaker during playback rather than the sound but even if we have a perfect match it does not mean the same sound is being produced. Sadly this is going to get worse and worse the more I be-labour the point. Ultimately even if you could measure the sound of the speaker within the room and determine, by eliminating the sonic effects of the room, the original sound produced you are still screwed because I will claim that the measurement devices are now changing the sound back to how it was - but only because I can.[6] And finally - its not my fault!!! Blame the quantum physicists that came up with their theories - you can apply them to real world situations but there is a danger your head will explode if you do.

I keep coming back to this thread to look at these amps again. Bloody good job on the appearance front Mark - really really good. The funny thing is I am not sure why they are so appealing - I have seen other, not dissimilar styles before. Maybe I have just gotten so used to wooden finishes that this is a refreshing change.

Robert, Hilarious post and not a million miles from my assessment either. I dont know - differences of style perhaps. I tend to spend some time selecting my phraseology so as not to offend whilst you....er.....leap in with both feet and a large cudgel? Rule of life number 32 - you can say anything and get away with it if you phrase it cleverly enough..... Another handy tip - gainsay your own argument within the post to cover yourself. Having said that - you know it is actually impossible to prove that the speaker is producing exactly the same sound from one room to another where the resultant sound differs. Think about it a little - kinda reminds me of Schroedinger's cat or one of those logical debates where you ask if a tree that falls in the forrest makes a noise if there is no-one there to hear it.

Not actually quite the same thing but interesting all the same. Few questions come to mind: If those same notes were recorded on different pianos could you pick which piano was played for your test? Can you recall those notes that were the basis of the test now?

Who, If you genuinely cant measure the effect of a persian rug (not that thick but high density) on a marble floor (such as I have) then we have a problem with the device..... I am sure proper acoustic devices do a lot more - one would certainly hope so as they are designed for the job supposedly but that does not pre-suppose that using more normal bits of furnishing cannot make a big difference in comparison to a bare room, for example. Empty my living room rings like a bell. Furnished it doesn't. Most audiophiles who have visited have expressed real envy over the room's accoustic properties. I would say it is probably amongst the best in the club and I do not own a single audiophile treatment.

Damn they look good!!! Good enough to leave them where they are (if you dont have kids, dogs etc.) Nice one indeed - if they sound half as good as they appear you are in for a real treat.

Impossible? I am certainly no master on the subject, but if you could obtain an impulse response of your room, I could convolve it with my music and get an idea of what your room sounds like by listening on headphones. I forget the term for the technique, but I've seen/experienced it numerous times....it's almost freaky. I beg to differ that the acoustical treatment process revolves around try it and hear it...if that were the case, it would really suck to treat some of the larger venues - like churches where you're mounting stuff high in the air and gotta navigate around the pews... Acoustical treatment can very much be a surgical process - it just requires one to be using the right tool. But hey, I suppose one could find a way to drive in a screw with a hammer [] Yikes! Do you find that an acceptable amount of time to dial in your system? What on earth is an impulse response? Who do I get one? I think you misunderstood my post. I was trying to illustrate that addressing room acoustics on a forum like this is almost impossible. I never heard on any professional implementation addressing this issue from afar - with no equipment - just pictures (maybe) and some descriptions. As for dialing in the sub - it was not quite the PITA is appears. I had it probably 90% of the way there within a couple of hours. Thereafter, as I played music on my system over the following months I would make adjustments where I thought the sound was off. We are talking small adjustments in the main, except for one time where I moved the implementation more for aethetic reasons than anything else. That certainly prolonged the process. I have to say with regard to this thread that I am somewhat surprised I was not taken to task over some of the things I claimed - particularly considering the war that is going on between other posters here. I wonder what I have to state to get attacked around here? Anyway - I did not write my claims to be attacked - it is a genuine report on what I have learned in my time as an audiophile. I just thought others would go balistic. As to the war: One side is saying, correctly that the sound produced by the speakers and amps (etc.) is not affected by the room. The other side is saying that the sound heard from the speakers and amps (etc.) is affected by the room. Guess what - both are (probably) correct although the former is assumptive and actually a lot harder to prove than you might think. One of the problems we have here, in dealing with room acoustics, is that in either extreme case the net result is poor sound. If it is a cheap and horrible system it will sound bad in the best room. Conversely if it is a massively expensive system in a dreadful room it will also sound bad. To argue that one is more important than the other is to argue that ears are more important than the brain that interprets the sound. To date my beagle - who has hearing many times more sensitive than mine has expressed no musical preferences. On the other hand a friend of mine (university professer in Math who happens to be profoundly deaf) has also never expressed an opinion.