My Speaker System

[Ravindra Desai]

Hello All,

In continuation to my posts My Digital Audio Processor and My Audio Amplifier, kindly find My Speaker System in this thread.
It is hand made from 11mm MDF pasted with black laminate.
It was designed with robust built in mind that should survive the Indian Courier system. I am not very good with aesthetics as I am with electronics design. But here it is for your comments:

For 2.1CH Surround:
1 x Dual Speaker Center
2 x Single Speaker Surrounds
1 x Single speaker sub-woofer,
1 x Ampli-decoder.

For 2.1CH Stereo
2 x Dual Speaker Center
1 x Single speaker sub-woofer,
1 x Ampli-decoder.

For 2.1CH Surround/ Stereo:
3 x Dual Speaker Center
2 x Single Speaker Surrounds
1 x Single speaker sub-woofer,
1 x Ampli-decoder.

Note that the last configuration uses a switch to change the configuration from stereo to surround and vice versa.

Also note that the Ampli-decoder can be programmed to support 2.0 Stereo also in which case two tower or book shelf speakers would be needed.

Let me know what you think.

Thanks in advance!!

Ravindra.

 

[tuff]

Cool. Looks Gothic. Can you give some more details about them? What drivers are those? are those tweeters in the center?

 

[elangoas]

It was designed with robust built in mind that should survive the Indian Courier system.

Ha ha.. Good one..

 

[Ravindra Desai]

Hello Tuff,

Satellites are 3" full-range with fabric roll surround
Subwoofer is 8" driver in a sealed enclosure. The driver has rubber roll surround.
Drivers are made by iWai.

I don't use tweeters. So I don't have to deal with cross-over networks.
My two-way stereo enclosures also use these speakers. 2 x 3" + 1 x 8" per enclosure.
In a two way system, I use 4 amplifier channels: one each for LLo, Lhi, RLo and RHi.

Regards,

Ravindra.

 

[Kannan]

I presume the wood grill in front is for protecting the speakers during transport and will be removed when listening.
How are you driving the individual speakers from four amplifier channels in a 2-channel mode? Is there an active network before the amp, that splits the frequencies between the woofer and the two full rangers in each enclosure?

I would not advocate 2.1 for music, but yes you can use it for movies with a proper decoder and a source file embedded in 2.1

 

[dr khanwelkar]

I would not advocate 2.1 for music, but yes you can use it for movies with a proper decoder and a source file embedded in 2.1

Kanan,
I have seen many people not advocating 2.1 for listening music,I have cadence arista speakers driven by Parasound a21 power amp.I have attached a sub-woofer to this system.I use the sub-woofer on demand .I "On " it if I listen to Rock,R.D Burman and rest of the bollywood music.I keep it off while listening to Indian classical vocal music.I have kept the crossover on the sub-woofer to 40 htz.-I was ridiculed about this by a Well known member of this forum.According to him the aristas can easily go down to 40,and hence what is the use of sub-woofer?The question seems to be theoretically correct,but practically I do find a difference.Please comment.

 

[Kannan]

Kanan,
The question seems to be theoretically correct,but practically I do find a difference.Please comment.

I am sorry sir...My big blunder. Since you were mentioning about center speaker, I assumed you were talking about a center speaker in stereo aswell. Sorry, I did not see the .1 which ofcourse means a subwoofer.

By the way I have two setups with bookshelves. One uses a sub and the other does not.
I actually like the one with the sub, as the bookshelf used with it produces awesome mids and highs and the sub is very nicely integrated to it.
There is no hard and fast rule in audio....
There are those who vouch by full ranges and those who prefer multi-way. I am a multi-way guy, and when you can have a woofer, midrange and tweeter to split frequencies, then why not a sub aswell to further split the lows.

In my long DIY journey, I have fiddled with numerous setups and within miserly budgets, and I have by far found active setups the most rewarding

 

[Ravindra Desai]

Hello Kanan,

I presume the wood grill in front is for protecting the speakers during transport and will be removed when listening.

The wooden front plate is for protection. But it need not be removed during normal use. There is no colouration of sound with the front plate and the sound field remains undisturbed. Both the 3"and the 8" drivers are very narrow dispersion type.

How are you driving the individual speakers from four amplifier channels in a 2-channel mode? Is there an active network before the amp, that splits the frequencies between the woofer and the two full rangers in each enclosure?

Source is connected to My Digital Audio Processor. It is capable of 2 in 6 out and is re-programmable. The post processing of input signal such as Surround decoding (in Surround application), DRC, Bass Management and Crossovers is all done in digital domain. The processed signal is input to My Audio Amplifier. This little baby can easily be dismissed as a good for nothing chip-amp. However I have made several tweaks to the typical datasheet applications to ensures that the sound quality is up there with the best.

I would not advocate 2.1 for music, but yes you can use it for movies with a proper decoder and a source file embedded in 2.1

My premium speaker configuration for stereo (2.0) that I recommend with my electronics (Ampli-processor/decoder) is Ahuja 12" fullrange speaker housed in a bass reflex reinforced enclosure (W x H x D) of 92cm x 144cms x 56cm with port dimensions of 10.2cmss x 10.2cms x 4.3cms (two ports)
Its huge. But for the price, its unbeatable. On Titanic track # 1,for the first 45sec, everything loose in the room will rattle at 2.5Wrms!!

In my first post I only mentioned 2.1Stereo/ Surround for most people on a budget.

Mine is a programmable system that can do it all: 2.0 Stereo. 2.1Stereo, 2.1Surround, 2/3Way Active.
With this digital processor platform, I no longer have to go to the drawing board for new customer requirements.

Hello again Dr.

According to him the aristas can easily go down to 40,and hence what is the use of sub-woofer?The question seems to be theoretically correct,but practically I do find a difference.Please comment.

Connecting the best source to the best amplifier to drive the best speakers is not enough in the digital age. Signal NEEDS post processing.
I have tried to reason it out here: https://www.hifivision.com/threads/what-changed-with-digital-audio.69388/

It should be a good read as I have tried to expose the audio industry as it is today.

If you give me time, I can bring my ampli-decoder (pre-configured for 2.0) over and we could give the Aristas a try, without sub-woofer.

Regards,

Ravindra.

 

[Hari Iyer]

looking cool. But why are the drivers output been blocked by wood on purpose. Is it pure aesthetics or have some technical reasoning? Curious to know.

 

[Ravindra Desai]

Hello Hari,

looking cool. But why are the drivers output been blocked by wood on purpose. Is it pure aesthetics or have some technical reasoning? Curious to know.

Thanks for your interest and concern. The reason for the front plate is protection and it is not blocking the sound at all.

Picture 1 in my post # 1 will give you an impression that the wooden plate is blocking sound. But if you take a look at picture 2, you will realize that there is at least 12mm gap between the face on which the speaker is mounted and the front plate.
1. The void on the front plate and the gap between the two faces is so big that is will not cause any obstruction to sound. Removing or retaining the front plate has no effect on the sound that you hear.
2. The 'gothic' looking void on the front plate and the gap between the speaker face plate and the front plate is so big that any waves generated by the speaker, bouncing off on the front plate and returning back to the speaker cone, with sufficient energy, so as to cause cone movement, which would be undesirable, is almost zero.

So I would not worry about the front plate at all. As another reference, take at look at the attached picture of a front grille. The pores are so small that you cannot see the speaker inside. But even in this case, waves generated by the speaker, bouncing off on the front plate and returning back to the speaker cone, with sufficient energy, so as to cause cone movement, which would be undesirable, is almost zero. So it will do no harm.
The speaker grille in the picture is of Bose Acoustimass series satellite speaker!

Now the cloth/ Fabric grille:
Speaker grille that has a cloth/ fabric actually absorbs sound frequencies, especially the high frequencies, depending on the cloth material and density.
So sound with and without cloth/ Fabric grille will be different, but not necessarily bad.
The cloth/ Fabric grille in some cases has the effect of soothing the sound. But then again it is a matter of personal preference.

Regards,

Ravindra.

 

[Kannan]

Thanks for your interest and concern. The reason for the front plate is protection and it is not blocking the sound at all.

Picture 1 in my post # 1 will give you an impression that the wooden plate is blocking sound. But if you take a look at picture 2, you will realize that there is at least 12mm gap between the face on which the speaker is mounted and the front plate.
1. The void on the front plate and the gap between the two faces is so big that is will not cause any obstruction to sound. Removing or retaining the front plate has no effect on the sound that you hear.
Regards, Ravindra.

I am quite surprised that the wood front does not make any audible difference to sound. The dispersion factor is highly variable over the sound spectrum.
Do use a simple RTA app on your phone and take a close measurement for each speaker (t a distance of not more that a foot from each speaker) by playing pink noise. Do this preferably late into the night when there is no other ambient noise. Then just compare the wave forms.

 

[Ravindra Desai]

I am quite surprised that the wood front does not make any audible difference to sound. The dispersion factor is highly variable over the sound spectrum.
Do use a simple RTA app on your phone and take a close measurement for each speaker (t a distance of not more that a foot from each speaker) by playing pink noise. Do this preferably late into the night when there is no other ambient noise. Then just compare the wave forms.

Hello Kannan,

With some help from my friend who has a calibrated mic and REW set-up, I recorded pink noise SPL levels of the speaker with and without grille.
The results confirm that there is no change in SPL level.
Attached are the snap shots of the exercise.
If you PM me your e-mail, I will send you the small movie clips (16MB and 12MB) of the same.

I thank you for your persistence. This is what keeps the forum alive and also gives me a chance to clarify/ verify things.

Regards,

Ravindra.

 

[Ravindra Desai]

Teasers of finish for 2nd generation builds....
Watch this space for more very soon!

Regards,

Ravindra.

 

[Ravindra Desai]

The enclosures for a Single Driver (12" Full Range) with Triple Port are ready.
This will be capable of 25Hz to 16KHz response.
It will be driven by 20Wrms amplifier and will be fit for serious, indoor, personal, stereo, listening.
After the concept (size, speaker fitment, grille etc.), it will be made in Russian Birch with Natural, Teak, Rosewood and Walnut finish.

Like discussed earlier, elsewhere, its massive but from a purist standpoint, this should be very close to what one would dream/ desire without making a big hole in the pocket

Very soon, I will post my personal listening impressions and then it will be then open to visitors for demo.

Till then....

Regards,

Ravindra.

 

[sadik]

Very huge enclosure. I guess its 4 Feet (H) x 2.5 Feet (W), cant guess the depth from front view.

 

[Ravindra Desai]

Very huge enclosure. I guess its 4 Feet (H) x 2.5 Feet (W), cant guess the depth from front view.

Hello Sadik,

I hope that you are doing well.

Yes, the enclosure is big. You are correct in your guess!! Its 126cms x 72cms x 72cms.
This needs no crossover and is very efficient. Measured group delay shows a flat line on 0deg level!
Also, it demonstrates what a well calculated enclosure can do to low frequencies.

Regards,

Ravindra.

 

[tuff]

That is HUGE. doesn't look like something you can lug over to Thane does it?

 

[sachu888]

Looks good. Which drivers ?

Regards
Sachin