Transmission Line Speakers using Peerless W3-LK76-PBK 3" Full Range Drivers

[aashish351]

It is safe to say that I have been seriously bitten by the DIY bug! Can't seem to stop DIYing different things!

Some of my good friends in AV industry are telling me that all of us 'audiophiles' go through a phase like this at some point but return back to good old commerical products... well, I hope to keep both the things going parallely without trying to replace one with the other!

Anyway, all thanks to Hari Iyer for taking the time out to calculate the design parameters for this project. The driver chosen is not an ideal full ranger, but I already had it bought for another purpose which didn't work out. So I thought might as well try a new thing!

Came across this interesting thread while searching for "what to do with these 3" drivers ordered for someother purpose"... http://www.hifivision.com/diy/21552-peerless-india-3-full-range-driver.html

And contacted the 'TL man' aka Hari Iyer.

The driver...

The sketch...

The box has been finished by the carpenter and I will post pictures soon...

 

[avidyarthy]

Use 3 spikes instead of the usual 4 nos. A lot easier to handle ... more practical ... would always remain grounded!

For more ideas ... get in www.diyaudio.com .... am sure, you would already know ....

 

[aashish351]

Use 3 spikes instead of the usual 4 nos. A lot easier to handle ... more practical ... would always remain grounded!

For more ideas ... get in diyAudio .... am sure, you would already know ....

That's a good idea! Thanks!

So you have also become one TL expert now!

 

[avidyarthy]

That's a good idea! Thanks!

So you have also become one TL expert now!

A lotta 'externals' you see on the speaker pics are my ideas .... hyeah:

 

[aashish351]

Here are the first round of pictures... the height of the speaker is less than I imagined. So decided to add legs with another base plate at the bottom with spikes to bring the height of the driver at the ear level.

Sketch of height increase plan...

 

[Kannan_madhu]

is it a straight line TL ?. could you share some more about the specs

 

[Flash]

Awesome job so far,

Would like to see the rear of the speaker.

Is the design based on a Quarter wave tapered TL.
What are you planning on using for Damping / Stuffing ?

 

[aashish351]

Thanks guys!

But the real appreciation goes to forum member Hari Iyer, who is the original TL designer for this project. Since he is now into commercial speaker design and manufacture, I cannot divulge design calculations. But I can try and answer a few basic questions... Hari might like to jump in and add whatever he wishes too.. (after all it is his design).

It is straight-line, not quarter-wave tapered TL. I am planning to use polyfil layers.

I will post pictures of rear soon... but it is a plain back. The terminus is at the bottom.

 

[avidyarthy]

^ jushhh like mine ... only difference being, here it is a full range driver, while my speaker is a two way design with a mid-woofer and a tweeter + an intricate xover + a curvature on the speaker top.

Me says, a Fostex 166eN driver could have done wonders with this design!

 

[panditji]

The speaker looks beautiful already even with out the finish...is this a local carpenter you are getting the cabinets made from?

 

[aashish351]

Yes, a carpenter who worked in my office. I saw his work and liked it. MDF is good material for clean build.

Sent from my Nexus S using Tapatalk 2

 

[aashish351]

^

Me says, a Fostex 166eN driver could have done wonders with this design!

Next project

Sent from my Nexus S using Tapatalk 2

 

[Hari Iyer]

Great build quality. I will call you once its completed for verifying the SQ

Awesome job so far,

Would like to see the rear of the speaker.

Is the design based on a Quarter wave tapered TL.
What are you planning on using for Damping / Stuffing ?

any damping material which is fibrous can do, say fiberglass, wool or coir or dacron.

 

[Abhishek]

Hi Ashish,

all the best with your speaker building. we all love to do it sometime !!

regards,
Abhishek

It is safe to say that I have been seriously bitten by the DIY bug! Can't seem to stop DIYing different things!

Some of my good friends in AV industry are telling me that all of us 'audiophiles' go through a phase like this at some point but return back to good old commerical products... well, I hope to keep both the things going parallely without trying to replace one with the other!

Anyway, all thanks to Hari Iyer for taking the time out to calculate the design parameters for this project. The driver chosen is not an ideal full ranger, but I already had it bought for another purpose which didn't work out. So I thought might as well try a new thing!

Came across this interesting thread while searching for "what to do with these 3" drivers ordered for someother purpose"... http://www.hifivision.com/diy/21552-peerless-india-3-full-range-driver.html

And contacted the 'TL man' aka Hari Iyer.

The driver...

The sketch...

The box has been finished by the carpenter and I will post pictures soon...

 

[ukjeyaraj]

Very nice work.

 

[aashish351]

Update time...

The modification to increase the height is completed by the carpenter. I am not very happy with the look now but it needed to be done to raise the driver to ear level.

I still need to stuff polyfil, solder wire to the drivers and waiting for the MX speaker terminals and banana plugs to be delivered for test fitting and trial.

Kept near the Dali Ikon 6, with the driver just rested in the cut-out to review the final look. height...

By aashish351 at 2012-07-17

By aashish351 at 2012-07-17

By aashish351 at 2012-07-17

By aashish351 at 2012-07-17

 

[aashish351]

Finally an update... couldn't finish the build for some time but finally installed the driver, stuffed the line, soldered wire and banana plugs and connected the amp. Have not finished the exterior purposefully...

There are no miracles to report and neither they were expected. But the sound is decent enough to be amazed by the potential of this design.

@Hari iyer.. you were absolutely correct about all three things.

1. The sound is surprisingly full for a 3" full range driver. There is decent upper mid bass.
2. This driver is harsh in the midrange but it is not so bad and will probably get better if we address the last problem...
3. Cone distortion. At low volume the performance is price defying. At high volume cone breakup causes distortion, harshness.

I will have to make the crossover as suggested by you. Can't avoid it.

All said, it cost me mere 4.5k to get low-fi but surprisingly decent sound for the money spent. I can see a lot of potential in this with say a fostex or other high end driver.



Sent from my Nexus S using Tapatalk 2

 

[Hari Iyer]

Finally an update... couldn't finish the build for some time but finally installed the driver, stuffed the line, soldered wire and banana plugs and connected the amp. Have not finished the exterior purposefully...

There are no miracles to report and neither they were expected. But the sound is decent enough to be amazed by the potential of this design.

@Hari iyer.. you were absolutely correct about all three things.

1. The sound is surprisingly full for a 3" full range driver. There is decent upper mid bass.
2. This driver is harsh in the midrange but it is not so bad and will probably get better if we address the last problem...
3. Cone distortion. At low volume the performance is price defying. At high volume cone breakup causes distortion, harshness.

I will have to make the crossover as suggested by you. Can't avoid it.

All said, it cost me mere 4.5k to get low-fi but surprisingly decent sound for the money spent. I can see a lot of potential in this with say a fostex or other high end driver.



Sent from my Nexus S using Tapatalk 2

Thanks for an update on the SQ of the speaker system. Expremintation with stuffing can help. Also the cross-over i suggested will help to reduce cone excursion at low frequency where in it allows the driver to operate at its linear range. You can call me for specifics if you wish since i cannot divulge more details on a open forum more so since i have gone commercial now.

Cheers, Hari.

 

[aashish351]

Thanks... i already have thr crossover details on email. but, i am thinking of replacing the driver with a better quality one. something thats fits the same design and cabinet cut out... maybe the crossover values will change after that.

 

[Hari Iyer]

Thanks... i already have thr crossover details on email. but, i am thinking of replacing the driver with a better quality one. something thats fits the same design and cabinet cut out... maybe the crossover values will change after that.

You can try S081E from peerless, it will work without any modifications to the enclosure (its 3.5") or the cross-over. This driver has a flat response in the pass-band as has a very good impedance curve too. The LK76 is very harsh in its mid-range and needs to be compensated for hi-fi usage. For a small project like this its not worth the effort to painfully calculate the values of the passive components to do the justice for a flat response in the higher-mid frequencies.