speakers placement

will speaker cables that can change the impedance like the MIT one rectify the prob?

my u.r amp is kt88 based . someone recommend me to try kt6550 tubes because they say kt88 sometimes sound fat and boommy. but i have emailed unison research founder Mr. Sachetti(correct spelling?) and he discourage me from using 6550 tubes.

i have learnt a lot from all your postings. thank you.

i think i have spent enough money and thus will concentrate on set up i.e. more experiment on speaker placement. yes uncle vic i will sure visit your place one day and learn some tips from u.

the reason i put up this post is i wish to get more inspiration on how to tweak the speaker position as i already out of idea myself better still if some picture can be posted so that i can try it at home

visiting KLAV show seeing how precisely jo place his speakers and woofer is a real eye opener for me

Thank you Wong KN for filling in what I did not know. I am more aware of what is happening now.

Long's system remains one of the most memorable system I come across, it offers dynamicsm without loosing composure of the Music Form like the physical attributes of soundstaging, dynamic contrast, image density, slew rate, tonal balance, etc. , all played at high volume! Very well endowed system worthy of recognition from me anytime! The acoustic treatment he installed in the room is not the main reason for the good performance of the system, but it is the speaker placement and ways of the system set up.

In Lam's speaker positioning, yes hificrazy, 1/3 and 1/5 theory may not work in a space not much of a "room". I would not expect it to work. IMHO, it must be placed in position that defy room boundary. In order to do that, huge speaker spacing with toe-in and place speaker close to side "wall". Unfortunately, such speakers positioning ruin the prestine stereo imaging quality of Harbeth SHL5! Excessive toe-in of SHL5 also undermind the depth field in staging.. etc.

In speakers placement, the L & R channels and listening position, formed a trilogy which is most basic but utterly essential relationship! Place this triangle in a given space, mildly altered the postion, altered the acoustics of the space.

The system set up of Lam's has rooms for improvement too, if such is the best he could do, then he should accept its setbacks and compromises. Because putting hifi system on shelf of HT system with TV in centre posted too much damages in my opinion. For instance, the TV screen would cause the centre image to sound flat, 'ghostly' and formless.

In any case, I find that Lam's system has not reached anyway near to optimised stage, so indulging in room acoustics at this stage is too soon too early IMHO. But at later stage, it would be definitely necessary.

Jo Ki


Precisely what I would wished Lam to explore, be it the speakers eventually have to sits in the middle of living room and completely rendered its spatial usage, or otherwise, this is what it takes to locate ideal speaker/room relationship. From there we could then adjust and rationalised to a compromised placement that the rest of the family could accept. We have to assume such level of uncompromised exploration to avoid making blatant statement of a product. This is being a responsible person.

After thinking a bit, I finally remembered some of my experiences with a pair of Spendor SP2/2 speakers I used to own. The thing is I have since changed to floorstanders since over 15 years ago so I forgot some of the issues of playing smaller speakers which needs to be placed on stands.

From what I remember and of course I am not saying Lamkochai definitely has not taken care of that area, but I remember I had a short bout with boomy bass with my SP2/2 and it was caused by improper seating of the speakers on their stands.

My opinion is that properly securing the speakers on the stands and then properly algining the stands and also properly seating them on the floor is of utmost importance, especially if we tend to play some bass heavy music. I remember experimenting with having the SP2/2 sitting on spikes, then experimenting with blu-tack to firmly couple the speaker to the stands. The thing is while the base of the speaker and the top plate of the stands are supposedly 'flat', they are never totally flat. So the area of contact between the speaker and the stand can often be very small, sometimes not even stable. So when the woofer is working hard, the speaker can rock about minutely on the stands. I remember I used blu-tack quite successfully because it ensured four definite area of contact between the speaker and the stand and while blu-tack is flexible, it is still managed to physically coupling the speaker to the stand, rather than simply having the speakers sit on the stands.

The other thing is to ensure the stand itself is properly seated on its spikes. Usually there are four and sometimes the four spikes are not properly seated in, resulting in the stands rocking around three of the spikes. Regarding the stands, I also remember even relatively heavy stands will still ring so I remember experimenting with filling them with sand and other damping material.

Finally, I also feel it is important to ensure the speakers are properly aligned. By this I mean the speakers must be vertical. This is more of an issue with ribbon speakers like my Apogees because they are line source rather than point source. But with multi-driver speakers like Harbeth, it is still important to ensure the tweeter is exactly vertically above the woofer, not slanted to one side. It is worse if the left and right speakers are slanted but by different degree and in different directions. For my Apogee, I use a plumb line to ensure the ribbons are vertical and also to ensure the tilt is consistent. For box speakers I don't see how a plumb line can be used. In this case, a leveller (what we call 'peng sui check' in chinese) can be put on top of the speaker, in two directions at right angles to each other to ensure the speakers are completely level.

Again I am not suggesting Lamkochai did not do this basic work but it doesn't hurt to bring it up and to remind him. Perhaps he should go through one round of this just to be sure ?

Lamkochai wrote:i have learnt a lot from all your postings. thank you.

i think i have spent enough money and thus will concentrate on set up i.e. more experiment on speaker placement. yes uncle vic i will sure visit your place one day and learn some tips from u.

the reason i put up this post is i wish to get more inspiration on how to tweak the speaker position as i already out of idea myself better still if some picture can be posted so that i can try it at home

visiting KLAV show seeing how precisely jo place his speakers and woofer is a real eye opener for me

Dear Lam,

Firstly, I would like to mention that you have right attitude for being open minded, readily accept suggestion; this will get you far one day.

Secondly, you are right about the spending bits; the minute you reach to deeper end of your pocket hoping to search for solutions to your hifi system, you loose the opportunity to address the essentials. Only after you took care of the fundamentals, you would realised true weakness of your system. Money does not solve all problems.

Stereo means exactly reproduction of 2 channels by micro-second differences between our 2 ears to create "space & time". The more exactly and accurately both channels works, the better it is the stereo works. By virtues of this requirement, it demands precise and accurate positioning and set up. Otherwise we are better of by listening to mono.

My LS3/5A and AB-1 is passively timed. Without it, the nature of their differences, seal box infinite speaker design (LS3/5A) and ported symmetrically loaded band pass crossover in 2nd order with 6dB roll-off slope (AB-1), would not work as perfect as I wished. The spacing is essential to bring both of them to work as a unit so that you do not hear them separately. Imaging having 4 speakers and make it works in a given space? So your 1 1/2 year is nothing as compare to what I have to go through with mine.

Remember, hifi is always about the journey in getting 'there', which the 'There' will never actually be 'here'. Enjoy the challenges against Nature of our listening environment & the Science of Physics in our system set-up.

Jo Ki

You are right Sifu

And welcome to the real world! Mr LamKochai.

"No pain No gain"

Wan Azami Hamzah wrote:Could be your room or your ears or a combination of both.
The best sound I had was living in a large attic in England in the 80s and had perfect acoustics by default I guess. The room had is a perfect rectangle and I fire the speakers widthwise. The ceiling slopes in front of me and the back. Floors were fully carpeted of course and the walls were plasterboard lined. System was Linn Sondek, Crimson amps and Dean Alto speakers on solid stands 2 feet from wall toed in. Nothing came close today. I don't get the superb bass reverb on 'The Goodbye Look' on Donald Fagen's 'Nightfly' anymore no matter how I look for it. Magic then. Or is it my aging ears?

I read your comment with interest because I've been searching for that particular bass performance too ever since I heard it way back then from the exact same song. And you know what, the source was also a Linn LP12 (with Grace arm) with AR11 speakers. I can only guess that it's the musicality of the LP12 and its ability to extract that bit more from the grooves. Btw, I'm still searching for it, albeit on CD.

Nothing came close today. I don't get the superb bass reverb on 'The Goodbye Look' on Donald Fagen's 'Nightfly' anymore no matter how I look for it. Magic then. Or is it my aging ears?

Izzamjazz wrote:

I read your comment with interest because I've been searching for that particular bass performance too ever since I heard it way back then from the exact same song. And you know what, the source was also a Linn LP12 (with Grace arm) with AR11 speakers. I can only guess that it's the musicality of the LP12 and its ability to extract that bit more from the grooves. Btw, I'm still searching for it, albeit on CD.[/quote]

Is still spin the Linn nowadays albeit with better arm and cartridge and the same Fagen vinyl occasionally. It's the room acoustics less than perfect, but I will get there someday soon. That track will be my guide for the acoustics I want and anything else I play should resemble the sound in the attic in ENGLAND i hope......

izamjazz wrote:
Btw, I'm still searching for it, albeit on CD.

I'm not too sure about 'The Goodbye Look' on Donald Fagen's 'Nightfly' album but having the privelege to compare between both version of CD and LP of Pat Metheny's "Travels" in my system, chances are likely your system would be unable to replicate the similar bass performance from CD.

I bought Pat Metheny's Travels LP more than a year ago and just got the CD version earlier this month --since I love the album so much. When I played the CD in my system that was when I figured out not only the bass but the overall life and dynamics of the CD were severely lacking in comparison to vinyl. There is so much more bass and "humanness" from vinyl that made CD sound pretty much lifeless.

The ECM recording of the vinyl album is the best there is and the performance of digital doesn't come close. If you want to experience the same bass performance from Donald Fagen's Nightfly album, I reckon you will have better luck getting that from the LP rather than CD. Now I realise why some people are still sticking to their vast vinyl collection.

Oooolllaaaa!
Vinyl vs cd again. Generally true ryder, thats why I have 3 record decks at home still. But there are exceptions though. I've heard a few 50s jazz lps sounding better on recent cds due to better retrieval of detail from modern mastering direct from the original master tape. Especially from the Bluenote and Columbia labels. Haven't heard the modern 180g vinylof these versions though so may again sound even better.
Anyway we're out of context here so lets go back to speaker placement aye?

Cheers.

Lamkochai wrote:i have the cd. not really that helpful. i spend 3 hours last night listening to track 9 and 13 and shifting my speakers. u may get the imaging correct using the test disc but when listening to other tracks and songs i doesnt sound right.

on one hand you've claimed "correct imaging" while on the other, some singer was projected with big mouth capable of swallowing buffalo what is actually what?

anyone auditioned lamkc's setup?



cheers

LKC, if you can't loan those ASI Resonator etc from CMY, try a free alternative, place some wine glasses at all corners and any death end where low frequency are trapped. Make sure the wine glasses bodies do not touch the side walls or bass traps so that they are free to resonate. If it help, then consider ASI Basic Resonator + Phase Corrector etc.
I have big speakers in a small dedicated room, and am using all the ASI stuff and also two DIY bass trap (4" NB x 2"Rockwool pipe sectional all the way up to ceiling height). And now I am quite happy with the sound, except the rattling of false ceiling for certain tracks with I still cannot tackle.

s8, u mean just a normal wine glass? ok i can try that because its free

tlkoo, the imaging means the "tok tok tok" sound produced by the knocking of "MUK Yu" from the cd. according to the cd if you can get all the 9 knockng moving from left to right with equal distance and the 5th knock at the middle just infront of seating position, your setting and imaging is correct. but in my system, i can get the "tok tok" sound correct but still when i play real cd, the sound stage may skew towards left or right side.

could someone audition to help diagnose? my shallow observation has taught me that reasonable imaging comes from balanced direct sound (from the speakers) with support from balanced reflective sound (from the reflective points)

while we could easily ensure direct sound is balanced to our ears, reflective sound surely faces more challenges and at this juncture, please imagine/visualise imbalanced reflective sound to sabotage your imaging!!! i went through the stage of putting blame to the air flow of my airconditioner when the imaging was not stable ha...

i have realised some way to assess if the ultimately perceived sound is balanced, alas too lazy to describe after all my typing may just go to waste, sigh...



worths 2cents

have fun

LKC, yes, thinner wine glass that can 'sing' when you slide a wet finger on the lid.
All enclosed space (your listening room included) will resonate when excited by energy, in this case sound energy. What happen is when low frequencies get inside the glasses, the glasses resonate and convert the low frequencies to its natural resonate frequency which is much higher, hence reducing bass boom. I had tried myself, and I can hear a difference when having 1, 2 or 3 glasses at the corners behind the spekers. But since I put on 17 nos. of Sugar Cubes from CMY, I have taken some glasses out except those at the corners behind listening position.
Have fun.

Guys,
Yeah try everything into your less than perfect acoustically room. Drag in few sackful of charcoal, a goat or maybe a dead chicken. Some false teeth over the speakers might work too.
Better fill those wine glasses with some red french wine and invite us over, get a bit high and maybe we'll forget some misgivings audio-wise and enjoy the music and a good company. How about that?

Lamkochai wrote:s8, u mean just a normal wine glass? ok i can try that because its free

tlkoo, the imaging means the "tok tok tok" sound produced by the knocking of "MUK Yu" from the cd. according to the cd if you can get all the 9 knockng moving from left to right with equal distance and the 5th knock at the middle just infront of seating position, your setting and imaging is correct. but in my system, i can get the "tok tok" sound correct but still when i play real cd, the sound stage may skew towards left or right side.

This means that your system are balance on the "tok tok tok" frequency range but not on others, especially the lower frequencies. This is due to the non symmetrical listening room dimension/arrangement. You can get an RTA to measure your room frequency response..it might help you to understand the abnormalities better.

Hi
My i share my experience with DEQ 2496 --a digital equaliser, dac , pre . It was reviewed a while ago and I bought one to play and may be useful in this instance .
The DEQ 2496 has a a mode to analysis the the frequency response of the system .
The DEQ play a pink nose through your amp and speaker and you place a microphone in your sitting position . there is a graphic display on the DEQ to tell the frequency that your are hearing vs the db. .
There is a mode in the DEQ to equalize it or to adjust it to any frequency pattern to your liking.
kp93300

hi

what mic do u use and do u use it for mid and high frequency?

I met up with Lamkochai in late august(last month) in Kuala Lumpur. He listened to my setup to see how and what direction I took, as regards to speaker placement, room acoustics and generation of bass contents.

Yet to bring him around to listen to setups centred around harbeth speakers. probably likely in the next few weeks or months, whenever we have a common free time la. so far only 1 teh tarik session together.

kp93300 wrote:Hi
My i share my experience with DEQ 2496 --a digital equaliser, dac , pre . It was reviewed a while ago and I bought one to play and may be useful in this instance .
The DEQ 2496 has a a mode to analysis the the frequency response of the system .
The DEQ play a pink nose through your amp and speaker and you place a microphone in your sitting position . there is a graphic display on the DEQ to tell the frequency that your are hearing vs the db. .
There is a mode in the DEQ to equalize it or to adjust it to any frequency pattern to your liking.
kp93300

The problem with using digital EQs to dial-in the perfect freq response is that while everything can be made to seem nice and flat on a graph, digital EQ doesn't do anything about varying reveb times.

Room modes (standing waves) wreak havoc on both the freq AND the reverb times and electronic EQs whether digital or analog is not really enough to resolve these problems.


A good listening room should besides having a relatively neutral dB characteristics, but also a relatively neutral RT60 signature across the audible spectrum.
There are various curves that sets some guidelines (like a Sabine, Eyring or Kuttruff curve) but they have trends emphasising slightly more reverb at the bass end is preferable, and slightly less reverb towards the treble.

Mugen,

>>>>digital EQ doesn't do anything about varying reveb times.

Does that mean that Digital Subwoofers (with parametric equaliser) and Audyssey MultEQ Pro, will not do any good for the reverb times? Is reverb times important for the bass frequencies ?

>>>>Room modes (standing waves) wreak havoc on both the freq AND the reverb times and electronic EQs whether digital or analog is not really enough to resolve these problems.

What would you suggest then ?

Can you elaborate more about the RT60 signature and the Sabine, Eyring or Kuttruff curve. What is the best way to measure this ?

What would you suggest as a good software for room modes simulation ?

carz wrote:

Does that mean that Digital Subwoofers (with parametric equaliser) and Audyssey MultEQ Pro, will not do any good for the reverb times? Is reverb times important for the bass frequencies ?

Reverb times are crucial across the entire audible spectrum. Bass, mid, & highs.

Stuff like the Behringer DEQ and the Audyssey only performs a "freq response" correction.

Whats still needed here is actually a "decay response" which is most commercial EQs cannot do.

Just for completeness, decay response CAN also be achieved in the digital / electronic level, but just that this would mean deploying very fancy and powerful DSP chips with many variables to achieve the same effect. It would require a DSP software engineer to code the artifical reverb control algorithms, and also would require a sophisticated field operator to implement as well. I don't envision a home/consumer market version of such a device anytime soon.
And then the hifi purists would thumb their noses at such a device because its a super sonic colourater built with fancy electronics.

carz wrote:
>>>>Room modes (standing waves) wreak havoc on both the freq AND the reverb times and electronic EQs whether digital or analog is not really enough to resolve these problems.

What would you suggest then ?

Acoustics panels. Expensive but these are the real deal. Check out websites like:
www.rpginc.com
www.primacoustic.com
www.realtraps.com

Personally I am not a fan of foam padding stuff because most home hifi rooms suffer standing waves the mainly in the bass dept, and for foam to really be effective at such low freqs (<100Hz), you need acoustic foam wedges that are probably a few ft. thickness. And foam tends to kill off too much energy in the midrange & highs, leaving a very "dead sounding" room. Which is fine if you wanna do recording on the evening news. But for music, its absolutely stale and not lifelike.

Problems with midrange and highs are more easily corrected with speaker placement, toe angles and listening position, due to the fact that a speaker's radiation pattern get more and more directional as the freqs go up. Unless of course you got a pair of MBL speakers with that omnipolar lantern-tweeter radiator.

carz wrote:
Can you elaborate more about the RT60 signature and the Sabine, Eyring or Kuttruff curve. What is the best way to measure this ?

What would you suggest as a good software for room modes simulation ?

RT60 means thats the time taken for the sound energy in a room to decay to minus 60 dB from its original impulse. the value is usually given in miliseconds.

For example: A bare room with solid walls, floor & ceiling would have very long RT60 specs. If u talk in that room, it sound very echo-eyyyyy.

A nice bedroom with thick carpets , big bed with fluffy pillows and heavy curtains would have a much reduced RT60 time.

http://en.wikipedia.org/wiki/Reverberation
And remember, Google is your friend