How does Bose create small speakers which produce powerful sound?

[SeekingProtection]

I'm not defending Bose or advocating for it.

According to research done by Dr. Bose, in a concert, the majority of sound reaching a listeners' ears is reflected sound and only a small portion of sound is directly from the singer and instruments, on this basis, they came up with direct/reflecting technology, in which a small portion of the drivers are towards the listeners, rest of the drivers are angled away from the listener, to create the ratio of direct sound and reflected sound found in a concert.

Does this make the speaker disappear?

 

[Nigel Goodwin]

I'm not defending Bose or advocating for it.

According to research done by Dr. Bose, in a concert, the majority of sound reaching a listeners' ears is reflected sound and only a small portion of sound is directly from the singer and instruments, on this basis, they came up with direct/reflecting technology, in which a small portion of the drivers are towards the listeners, rest of the drivers are angled away from the listener, to create the ratio of direct sound and reflected sound found in a concert.

Does this make the speaker disappear?

No, it's just the usual Bose bullsh*t.

 

[crutschow]

Most of the sound coming to you in concert hall may be reflected, but the reverberation times in a hall are greatly different from those in a small house room.
So using speakers that give a reflected sound in you house will give a much different sound than from the hall.
And you still will be able to point to the speakers as the source of the sound.

Instead, what you want to do is minimize the effects of your room on the reproduced sound.
A good stereo recording already includes the reflected sound from the hall, so you just want to hear that, not the added reflected sound from your room.

Linkwitz's speaker designs use dipolor sound output to minimize the effects of the room and the "box speaker sound".
Read his articles if you want to better understand that.

 

[unclejed613]

According to research done by Dr. Bose, in a concert, the majority of sound reaching a listeners' ears is reflected sound and only a small portion of sound is directly from the singer and instruments, on this basis, they came up with direct/reflecting technology, in which a small portion of the drivers are towards the listeners, rest of the drivers are angled away from the listener, to create the ratio of direct sound and reflected sound found in a concert.

while this is true when an orchestra plays in a "shell" (half-dome) without any active amplification, it's not true of the majority of modern music that requires amplification. modern music is played direct, and not bounced off of back or overhead surfaces (at least not intentionally). there have been many experimental sound systems tried with the goal of "filling" a venue with sound. the most famous of these was the "Wall of Sound". i remember when Bose came out with "direct-reflecting" pro-audio systems. not a whole lot of musicians used them because they were tricky to get set up properly. when Bose came out with home speakers using the same principal, most people's listening rooms are too small for the "direct-reflecting" method to be useful.

 

[Nigel Goodwin]

most people's listening rooms are too small for the "direct-reflecting" method to be useful.

Depends how (and why) you do it

Horn speakers are efficient, and known for their audio quality - as the horn effectively matchs the impedance of the driver to the impedance of the air (an acoustic transformer). But horns for bass frequencies are HUGE, the answer is to fold them (folded horns) - still BIG - a better answer is to design a folded horn that points in to the corner of the room, using the two walls as the final part of the horn.

I used to know a guy who designed and built a pair of speakers in this fashion for doing discos, and the efficiency meant he only used a 10W amplifier. Mind you he was a seriously clever guy, and had worked as a designer for a number of major electronics and audio companies.

On the same vein?, I also knew another guy (again seriously clever), and he designed and built his own high quality audio system - building the bass units in the walls of the house, effectively making the largest infinite baffle speakers possible. I wouldn't have liked to live near him though!

Incidentally, I've described both as 'seriously clever', and you've probably heard the saying there's a fine line between genius and insanity - I always considered both were teetering on the edge.

 

[SeekingProtection]

Depends how (and why) you do it

How and why would direct/reflecting be useful?

 

[crutschow]

How and why would direct/reflecting be useful?

I doubt that it is in any typical listening area.

 

[SeekingProtection]

I doubt that it is in any typical listening area.

I asked that since Nigel Goodwin said: "Depends how (and why) you do it", when unclejed613 said direct/reflecting is not useful in homes because rooms are too small.

I wondered why he would say that after calling it bullsh*t.

 

[unclejed613]

How and why would direct/reflecting be useful?

there are some speaker manufacturers that have "bipolar" midrange drivers. what they've got in their tower speakers are usually two midrange drivers on the front of the cabinet, and one on the back with reverse phase wiring. most of the sound is direct from the front side drivers, and a smaller amount of delayed sound from the wall behind the speaker. this is in contrast to Bose and their 901 series speakers from around 1975 where there were 9 drivers on the back of the speaker, and one on the front. back in those days they made some amplifiers that you could likely use for arc welding (the model 1801 IIRC). it was a two channel amplifier rated 800W/ch into 4 ohms. it was also very big and heavy with the output transistor heat sink wrapped around 3 sides of the chassis. i have more recently (about 10 years ago) repaired a couple of 1801 Series V amps. they are still heavy, and about the same amount of power, but amazingly fit in a 1U rack space instead of the 3U space the original 1801 amps took up.

 

[Reloadron]

In my life today things go a little like this.

Wife: What was that?
Me: What was what?
Wife: That noise.
Me: What noise?
Wife: You really need to consider a hearing test and hearing aids.
Me: Huh?

Heck, my bike has AM FM and a Cassette Deck with 26 year old speakers and it sounds fine to me but finding cassette tapes is a problem. I have given some thought into replacing the sound system but the existing system still sounds OK to me. During my much younger years I really enjoyed quality audio but today just about anything remotely discernible sounds fine to me. Sort of like that beauty is in the eye of the beholder thing.

Ron

 

[gophert]

In my life today things go a little like this.

Wife: What was that?
Me: What was what?
Wife: That noise.
Me: What noise?
Wife: You really need to consider a hearing test and hearing aids.
Me: Huh?

Heck, my bike has AM FM and a Cassette Deck with 26 year old speakers and it sounds fine to me but finding cassette tapes is a problem. I have given some thought into replacing the sound system but the existing system still sounds OK to me. During my much younger years I really enjoyed quality audio but today just about anything remotely discernible sounds fine to me. Sort of like that beauty is in the eye of the beholder thing.

Ron

Your Harley has a nice vibration all the way up through the speakers and that likely gives you that nice room-filling (behind-the-fairing-filling) sound via V-Twin Audio Impingement Mixing.

 

[audioguru]

[QUOTE="Reloadron, post: 1352591, member: 146097"Heck, my bike has AM FM and a Cassette Deck with 26 year old speakers and it sounds fine to me. The existing system still sounds OK to me. During my much younger years I really enjoyed quality audio but today just about anything remotely discernible sounds fine to me.[/QUOTE]
As you age then your high frequency hearing normally has losses. If you ignore the losses then your brain forgets about high frequencies.
I caught my high frequency hearing loss before my brain did so now with my hearing aids I hear very well like when I was young, and the hearing aids do useful tricks (noise reduction, extra sensitivity, muting and front-rear directionality) that normal hearing cannot do.

 

[nsaspook]

Not exactly my "thing", but I admire your thorough approach to a solution that works for you.

JimB

It's a fun hobby.
**broken link removed**

 

[gophert]

It's a fun hobby.
**broken link removed**

What the heck is...

Independent Power & Glory Switches

 

[nsaspook]

What the heck is...

They eliminate jittery this and that.
**broken link removed**

 

[Nigel Goodwin]

How and why would direct/reflecting be useful?

As my post explained, when using the reflections as the final part of a folded horn.

 

[unclejed613]

It's a fun hobby.
**broken link removed**

reading the specs, it looks like Rane hired the same tech writer that writes Sony (and Bose) spec sheets.

isn't Rane one of the companies that made ionophone tweeters?

 

[nsaspook]

reading the specs, it looks like Rane hired the same tech writer that writes Sony (and Bose) spec sheets.

isn't Rane one of the companies that made ionophone tweeters?

They have been into DJ stuff for a while.
**broken link removed**

 

[unclejed613]

you'll need [this amplifier] if you want to use the full potential of that PI-14...

 

[crutschow]

you'll need [this amplifier] if you want to use the full potential of that PI-14...

Is that what this guy is listening to?