My Listening Room

[GeorgeO]

Thad calls it an industrial machine looking part-I think it looks a lot more menacing and bomb like!

 

[Thad E Ginathom]

Yes, George, I can see that too! Very apt!

 

[tiger0691]

I wish I could be sitting in the center of your room for a minute.

 

[spirovious]

How is Parasound halo series performing in your setup?
Do they match with Anthem?

 

[rajagopal_j]

Raj, I am quite inspired by your work with the open baffles. Have a question, I've noticed personally that the speaker has to be driven more if used in such an arrangement, compared to a full baffle (either bass reflex, acoustic suspension or horn). Is this true?

In very simple terms, a box speaker design works to use the sound waves originating from the rear of the driver to augment the sound from the sound waves originating from the front. It does nothing to the actual forward sound waves. Also most box designs augment only on the lower frequency spectrum.

So for the upper mids and hf there is no difference between a box and OB in terms of driving power required.

Now how much augmentation is required for the natural bass sound, which comes from a kick drum or a bassoon or a cello or the low note in a piano? This becomes a personal choice. If you want the augmentation, then yes you will have to drive the LF a lot more than in a traditional box design.

There is also the matter of balancing the HF and LF drivers for loudness due to differences in the efficiencies.

I use a 15wpc amplifier for driving the LF and a 1.5wpc amplifier for driving the HF. The idea is primarily for balancing the efficiencies of the drivers.

Another dumb question, as I have never used a horn tweeter before. Does the metal horn assembly actually do the job or a speaker cone or does it just direct the sound? Asking as I have seen some designs where a paper cone or dome tweeter is used behind a horn shaped assembly for making the high frequencies directional.

A horn itself doesn't produce sound. Its a shape which works to provide an acoustic impedance match between the sound produced and the air in the room. This results in maximising the efficiency of sound produced or received. Your ear is also a horn but on the receiving end, and also a reason why we hear differently as the throat aperture of the horn in our ears vary from person to person, varying the efficiency in receiving.

You can put a horn in front of any audio source and it will definitely increase efficiency at least in a very crude manner based on the horn design and the source.

The compression driver produces the sound and the horn increases the efficiency of the driver. In my case, the horn is designed for a 60:40 wide:tall spread as well for use in a movie theatre.

It seems that it is called a compression driver, but I'll leave further explanation to the experts, as I wouldn't have a clue.

The area of the diaphragm is much larger than the aperture of the driver. The sound produced gets compressed when it enters the throat of the driver and then exits via the horn.

I think this image and link explains it best.

source:Compression driver - Wikipedia, the free encyclopedia

 

[rajagopal_j]

I wish I could be sitting in the center of your room for a minute.

Sure, whenever you are in Chennai.

 

[shafic]

In very simple terms, a box speaker design works to use the sound waves originating from the rear of the driver to augment the sound from the sound waves originating from the front. It does nothing to the actual forward sound waves. Also most box designs augment only on the lower frequency spectrum.

So for the upper mids and hf there is no difference between a box and OB in terms of driving power required.

Now how much augmentation is required for the natural bass sound, which comes from a kick drum or a bassoon or a cello or the low note in a piano? This becomes a personal choice. If you want the augmentation, then yes you will have to drive the LF a lot more than in a traditional box design.

There is also the matter of balancing the HF and LF drivers for loudness due to differences in the efficiencies.

I use a 15wpc amplifier for driving the LF and a 1.5wpc amplifier for driving the HF. The idea is primarily for balancing the efficiencies of the drivers.



A horn itself doesn't produce sound. Its a shape which works to provide an acoustic impedance match between the sound produced and the air in the room. This results in maximising the efficiency of sound produced or received. Your ear is also a horn but on the receiving end, and also a reason why we hear differently as the throat aperture of the horn in our ears vary from person to person, varying the efficiency in receiving.

You can put a horn in front of any audio source and it will definitely increase efficiency at least in a very crude manner based on the horn design and the source.

The compression driver produces the sound and the horn increases the efficiency of the driver. In my case, the horn is designed for a 60:40 wide:tall spread as well for use in a movie theatre.



The area of the diaphragm is much larger than the aperture of the driver. The sound produced gets compressed when it enters the throat of the driver and then exits via the horn.

I think this image and link explains it best.

source:Compression driver - Wikipedia, the free encyclopedia

Nice explanation, truly appreciated.
regds,
shafic

 

[Thad E Ginathom]

The area of the diaphragm is much larger than the aperture of the driver. The sound produced gets compressed when it enters the throat of the driver and then exits via the horn.

I think this image and link explains it best. ...

I've seen the diagram before, but it took your words to explain it

 

[reubensm]

Perfect, this is what I was looking for. I am going to get down to my speakers in the near future, the plan is to have 15 inch drivers for the lows, full rangers for the mids and a tweeter bank (yes, I love sparkling highs) for the highs.

Have couple of questions. I have experienced a pair of 4 inch paper cone tweeters in the past. They were locally made (HRC if I'm not wrong) and they were quite aggressive. If one is looking for bright tweeters, is it appropriate to take the large paper cone route, the horn route, the dome route or the liquid cooled ferro route?

Also, When I was a kid, I recall Dad using a tweeter bank consisting of 6 four inch speakers (not sure whether they were actual tweeters or general purpose speakers) mounted on a board with a 3 row, 3 column configuration. I recall he had 10 mfd coupling for the bottom row, 8 mfd for the center row and 4.7 mfd for the top row. This tweeter bank was used with a low frequency speaker in a large horn loaded enclosure. This speaker system used to be a huge draw locally, back in those days. Not sure about the theoritical aspects behind the idea but despite being an engineer, Dad always took the approach of breaking the rules to get something that sounded nice to his ears. The question is, does it make sense to replicate something like this? Yes, speaker efficiency is a criteria and also, the ability to control the overall output of the array.

In very simple terms, a box speaker design works to use the sound waves originating from the rear of the driver to augment the sound from the sound waves originating from the front. It does nothing to the actual forward sound waves. Also most box designs augment only on the lower frequency spectrum.

So for the upper mids and hf there is no difference between a box and OB in terms of driving power required.

Now how much augmentation is required for the natural bass sound, which comes from a kick drum or a bassoon or a cello or the low note in a piano? This becomes a personal choice. If you want the augmentation, then yes you will have to drive the LF a lot more than in a traditional box design.

There is also the matter of balancing the HF and LF drivers for loudness due to differences in the efficiencies.

I use a 15wpc amplifier for driving the LF and a 1.5wpc amplifier for driving the HF. The idea is primarily for balancing the efficiencies of the drivers.



A horn itself doesn't produce sound. Its a shape which works to provide an acoustic impedance match between the sound produced and the air in the room. This results in maximising the efficiency of sound produced or received. Your ear is also a horn but on the receiving end, and also a reason why we hear differently as the throat aperture of the horn in our ears vary from person to person, varying the efficiency in receiving.

You can put a horn in front of any audio source and it will definitely increase efficiency at least in a very crude manner based on the horn design and the source.

The compression driver produces the sound and the horn increases the efficiency of the driver. In my case, the horn is designed for a 60:40 wide:tall spread as well for use in a movie theatre.



The area of the diaphragm is much larger than the aperture of the driver. The sound produced gets compressed when it enters the throat of the driver and then exits via the horn.

I think this image and link explains it best.

source:Compression driver - Wikipedia, the free encyclopedia

 

[rajagopal_j]

Perfect, this is what I was looking for. I am going to get down to my speakers in the near future, the plan is to have 15 inch drivers for the lows, full rangers for the mids and a tweeter bank (yes, I love sparkling highs) for the highs.

Have couple of questions. I have experienced a pair of 4 inch paper cone tweeters in the past. They were locally made (HRC if I'm not wrong) and they were quite aggressive. If one is looking for bright tweeters, is it appropriate to take the large paper cone route, the horn route, the dome route or the liquid cooled ferro route?

Also, When I was a kid, I recall Dad using a tweeter bank consisting of 6 four inch speakers (not sure whether they were actual tweeters or general purpose speakers) mounted on a board with a 3 row, 3 column configuration. I recall he had 10 mfd coupling for the bottom row, 8 mfd for the center row and 4.7 mfd for the top row. This tweeter bank was used with a low frequency speaker in a large horn loaded enclosure. This speaker system used to be a huge draw locally, back in those days. Not sure about the theoritical aspects behind the idea but despite being an engineer, Dad always took the approach of breaking the rules to get something that sounded nice to his ears. The question is, does it make sense to replicate something like this? Yes, speaker efficiency is a criteria and also, the ability to control the overall output of the array.

Matching the speakers for tone, I believe is going to be your biggest problem. Matching the efficiency and tonality of the drivers is paramount. Full rangers usually don't mesh well with other drivers, I don't have a theoretical reason as to why. What is the purpose behind the tweeter bank? Why do you believe 9 tweeters will do the job better than 1?
It would definitely help if we know more about the actual drivers you are planning to use?

 

[reubensm]

Matching the speakers for tone, I believe is going to be your biggest problem. Matching the efficiency and tonality of the drivers is paramount. Full rangers usually don't mesh well with other drivers, I don't have a theoretical reason as to why. What is the purpose behind the tweeter bank? Why do you believe 9 tweeters will do the job better than 1?
It would definitely help if we know more about the actual drivers you are planning to use?

yes, matching is always a problem, guess will have to go with what sounds best.

We've always been fans of the wall of sound technique and hence the idea, logic used was for greater throw on the highs, guess a single driver-based horn unit will achieve that anyways