Solving the BOSE issue!

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Originally Posted by Resident Loser

...I'll try to locate my pink-noise plots over the weekend, but at the very least I'll just re-plot the inverse of my current settings on my half-octave graphic and provide some further info...at least re: 901-lls...and they were done in a real-life living room and with the best of intentions.

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I didn't have the time to locate my originals, but the following graph is the inverse of the settings currently on my SAE 2700B half-octave equalizer...

Attachment 1765

It took a while even locating multi-cycle, semi-log paper I could download that could be re-worked from a .pdf to a .jpg for my purposes...and me being an avowed Luddite and computer-illiterate had a devil of a time at the whole venture...plus now downsizing to fit the site's requirements...anywho!!!

jimHJJ(...have at it...)

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Originally Posted by thekid

If I may attempt to bring this back on topic somewhat .....and ask a newbie question.....

Re-The FR gaps that were mentioned earlier referencing the cubes- are they (FR gaps-Not the issues with the cubes) correctable using tweaks from your reciever or other methods? For example if the speakers over emphasize mid-bass could you change your x-over? As I mentioned I don't really understand the intricacies of FR and sense it came up here I thought I'd ask.

Thanks for any education in this area you all could provide.

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To a point, you can correct for unevenness in the frequency response and alterations caused by the room acoustics. But, a frequency gap like you see with the Bose Acoustimass occurs at the extreme physical limits of the satelite and bass module units. EQ'ing or processing won't make those speakers do what they are physically incapable of doing.

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Originally Posted by Resident Loser

...I keep seing references to the Sound and Vision article from 1999 from which those specs were quoted...and yet more recently in November '04 Ken Pohlmann did a review of the Lifestyle 38 system that seems to have no axes to grind...and didn't call into question Dr. Bose's lineage or ulterior motives in his supposed quest to dominate the A/V world...

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Uh, and that 2004 review that Pohlman wrote did not include any technical measurements, which is very unusual for S&V. Let's see, S&V reviews for other comparable HTIB packages DO include the technical measurements, while they are excluded from the Bose Lifestyle 38 review. No axes to grind evident, but I would hardly call this type of exclusionary cherry picking objective.

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Getting back to those numbers...I realize no loudspeaker exists in an anechoic vacuum, but putting any Bose loudspeaker in that test environment seems to be somewhat self-serving...Direct/Refelecting being the operative phrase, sorta' kinda' intimates that relections are what they are...well...a somewhat important , dare I suggest integral, part of the mix...Hmmm...anechoic...reflections...anechoic... reflections...DANGER! DANGER! This does not compute Will Robinson!!!

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And here's where the Acoustimass differs ... that direct/reflecting design is adjustable by the USER, and can in fact be positioned as a conventional direct firing satellite unit. This is very different from Bose's direct/reflecting bookshelf and floorstanding speakers, or dipolar or bipolar or omnipolar speakers, which have the radiating pattern fixed into the speaker design.

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Originally Posted by Resident Loser

and if they were, given the fact that the Bose owners manual indicates they should be aimed to give a balance of direct and reflected sound, the test parameters are therefore suspect IMO. Might the fact that they are supposed to be off-axis to each other have skewed the numbers? and all the while, conveniently fitting in the apparent Bose-bashing agenda? If so, how convenient...

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S&V conducts all of their speaker tests using on-axis measurements. That's why their results are comparable from graph to graph. David Ranada and more recently Tom Nousaine have been conducting these tests the same way for years. No Bose bashing agenda from them, and no Bose favoritism from them either, unlike Pohlmann's approach of only telling the good news, and leaving out the details.

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Originally Posted by Resident Loser

That dip in the 200-300Hz region is at the crossover point between the bass mod and the satts...if the system was placed in a real room (not in a anechoic environment) would things have been more linear? Keep on repeating...direct/reflecting...direct/reflecting...

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Nope, the wall reflections and room placement cannot create what isn't there in the first place. The existence of this frequency gap is audible during normal listening. As I noted before, male voices sound very strange on an Acoustimass system.

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Originally Posted by Resident Loser

The rise to a +4 dB peak and subsequent fall @ 5-7kHz region...could the axis alignment (if that's how it was indeed done) have been responsible?

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Another very audible phenomenon in a real world setup. Despite their steep dropoff in the highs, the Acoustimass systems subjectively sound bright much of the time, and that goes along very well with that peak that occurs around the 5 kHz mark. However, this brightness does not apply to higher pitched sounds like violins, trumpets, cymbals etc. With those sounds, the Acoustimass systems sound almost muffled.

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Originally Posted by Resident Loser

I'll try to locate my pink-noise plots over the weekend, but at the very least I'll just re-plot the inverse of my current settings on my half-octave graphic and provide some further info...at least re: 901-lls...and they were done in a real-life living room and with the best of intentions.

jimHJJ(...now I think I'll have an apple turnover and some OJ...)

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Interesting results that you posted. The most notable aspect that I spotted was the big difference in how the L and R speakers measured. Was this room asymmetrical?

I think that we are going back and forth on something that is just not really going to go anywhere. Chances are if you do not like Bose ...you are never going to like them. If you have a sweet system already...then you don't really care about Bose and that's the end of that. If you DO like Bose...then YEAH for you. I don' think it's right or wrong to like something because it's all a matter of taste. Fact of the matter is that Bose is right for certain people because of the price, the name, and to them it meets the need. For others, like most of us that write in this forum...we don't have any interest in Bose and that's fine too.

...being the dimwit that I am, on review I noticed the right-channel peak @ 10k...actually since my EQ controls are +/- 16dB max, that point in the plot should be 5dB lower...like this:

Attachment 1772

And in answer to your inquiry:

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Originally Posted by Woochifer

Interesting results that you posted. The most notable aspect that I spotted was the big difference in how the L and R speakers measured. Was this room asymmetrical?

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Well, ostensibly the room (10x14 or so) is visually a rectangle and my speaks are along the longest wall...however, directly opposite the left speaker is a foyer, alcove, place to wipe your feet, roughly 4ft. square...standing in it is a sonic nightmare, and I'm fairly certain it has an effect...to say the least...and then there's the picture window in the short wall in between...

As if that weren't enough, there is a similar situation at the right speaker. That mirror-image "alcove"-like space actually extends into a hallway, which at least doubles that leg of the room...and then there's the archway that opens into the dining area...so sonically, the space is sorta' like a U-shaped affair...and then of course comes the furnishings...all in all, a great big pain in the (r)ear...

I had used a laundry-list of SPLs on a legal pad for the EQ set-up...Since transferring those numbers to the proper plotting medium, I think I can now visually account and correlate for nearly every blip and bloop in the response curve.

jimHJJ(...all-in-all, it's been a beneficial exercise...)

While you guys are trying to figure out why Bose sounds so bad, I'm listening to Pink Floyd's 'Dark Side of the Moon' on my vintage 901s, and they sound perfect.

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Originally Posted by njspeer

While you guys are trying to figure out why Bose sounds so bad, I'm listening to Pink Floyd's 'Dark Side of the Moon' on my vintage 901s, and they sound perfect.

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I'll be listening to Rush 2112 on my Bose, on my way home in a few minutes. I'm sure that I'll enjoy it as much as I did this morning. But when I get home, I'll turn on my Yamaha mid-level receiver and it will sound much better, as it always does. I'll pop open a brew and maybe make myself a Pb&J sandwich.

I spent $25 on my cables. Hope that's OK. And My Infinity speakers still have the crossovers they came with.

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Originally Posted by GMichael

I spent $25 on my cables. Hope that's OK.

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It's okay this time. Don't let it happen agian.

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Originally Posted by njspeer

It's okay this time. Don't let it happen agian.

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I'll try not to. I'm thinking $38 next time. But that's only because it's double insulated. I doubt that helps the sound, but it does meet building codes for installing wire inside your walls.

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Originally Posted by njspeer

While you guys are trying to figure out why Bose sounds so bad, I'm listening to Pink Floyd's 'Dark Side of the Moon' on my vintage 901s, and they sound perfect.

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..."...some of you guys..."...I've enjoyed mine since '75...

On the self-titled Heart album there is some between-cut banter (just before "Say Hello" I think) in which the voices, and the coin they're tossing on the ground, sound about as immediate and in-the-room-with-you as may be possible in recorded form...also during "Magic Man" (Dreamboat Annie) there is a synthesizer glissando that drops the frequency of a bass line into the Marianas Trench...smooth even, tight and powerful all the way to the bottom...of course the room EQing helps in smoothing no doubt, but they've got an excellent bottom and top-end IMO...

And in PFs title cut on "Wish You Were Here" there is that acoustic guitar intro that blows me away every time...and since I have played guitar since 1966, I have the reasonably adequate ability to know what one sounds like.

Smaller, less futzed-with disks, particularly jazz with acoustic bass, the bass is so present (and I don't mean loud and overbearing) I'm sometimes amazed...bowed lines are incredible...you can almost feel the rosin on the bow...details...you want details...I also find them to have very good localization and presentation of depth...

R. Carlos Nakai's "Canyon Trilogy" is a solo album of Native American flute music and it's sound is positively ethereal...as I'm sure it was intended...the 901s do it justice...

And I don't mean to give the impression of a generalized euphony, because there are albums that just plain s*uck for one reason or another...good recordings sound good/bad ones, bad...

jimHJJ(...and that's the name of that tune...)

Wooch-JoeE

Thanks for the education. FR Gaps is a term used frequently around here and I just needed some clarification. Wooch I think your point regarding room accoustics is one sometimes overlooked in many speaker discussions.The hardcore tend to balance the whole equation where newbies such as myself often don't have the time or resources to deal with that issue and it is probably a very critical component with how a speaker sounds no matter who the manufacturer. As mentioned in some of the earlier threads the "Direct/Reflecting" technology does affect how a Bose speaker is going to sound and therfor room accoustics and speaker position are more critical for Bose than with other speakers. I am not saying that makes them better or worse it just a factor to consider when people start talking about measuring Bose-the original topic of this thread.

The bottom line is this, if you like them then fine :-)
I still would like to measure one but dont feel like spending 50$ to buy one. So if anyone near me is interested in some measurements let me know.

Well Flo I do travel alot but Bavaria is not on my schedule or I'd bring mine over and let you measure them.

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Originally Posted by thekid

Well Flo I do travel alot but Bavaria is not on my schedule or I'd bring mine over and let you measure them.

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Yeah right :-)

But then again its pointless to measure them. I personally cant stand more then +-1.5db difference across the entire spectrum. You could buy a Tact RCS and try to get it time, phase coherrent with a flat responce.

-Flo