DIY : Transmission Line Speakers.

I went through the link, but this project was meant to be used with the Fostex driver. Hope you are also using the same driver or a driver with similar TS parameters. The line length, damping coefficient and cross section area varies with the driver and cannot be directly substituted. The harmonics will not match with the acoustic impedance and you will need to experiment with the damping in case you hear some mid-range anomalies. The acoustic impedance is important to have the low frequency lift you get from the line length or you risk having standing waves in the line.


Yes, the fostex speaker is having more or less the same speaker parameters. I believe direct substitution worked well in this case.
I did experiment with damping a little, but there was little difference, and the original damping conditions sounded the best. As far as my ear can tell, Zakir Hussain's Tabla hasn't sounded crispier and more blissful to me :)
The low frequency lift is perfect (for my ear). There is little distortion that i can hear in the lows, but that is also at high decibel levels. The low frequencies at low volumes is breathtaking!

I know exactly what standing waves would sound like or feel like. In my previous projects, this problem was evident and i dont seem to get that feeling in these speakers.

I still have to do the port length determination, could you please tell me how i should proceed for doing that ?
Thanks :)
 
Yes, i actually screwed up a little on one of the cavity for the mid bass driver. I bored in a little extra. Had to fill up with m-seal ... you might have seen a picture of it in the collection. after it dried, i used a file to make a perfect circle.:)
Thanks man !

DIY is a process where you learn in the course of the journey. I didn't go through the detailed pics and hence didn't notice.:eek:

Nevertheless, it doesn't show up after the driver is installed and I don't think would affect the SQ in an adverse way. So it's ok I guess.
 
DIY is a process where you learn in the course of the journey. I didn't go through the detailed pics and hence didn't notice.:eek:

Nevertheless, it doesn't show up after the driver is installed and I don't think would affect the SQ in an adverse way. So it's ok I guess.

Yes, I totally agree with you ! :)
It does not affect the SQ at all, cause it driver fits in perfectly sealing the cavity :)
 
Hi Pranav,

Welcome to the TL Club :clapping:

1 thing is for sure, once you get into the TL Speaker Club, you remain there :lol:

As for the bass, I agree with you 100%

Congrats & enjoy!

:)
 
looking at haris probing questions and Pranavs replies.... i like the way the replies sound enthusiastic. Its Ok to experiment, trip and getup and run again. That and de-mystyfying things which seem complex ( "Go where no man has been before.." Star Trek ) is what makes DiY so worthwhile.

Damping and stuff is good as long as the user is happy with the enclosure..maybe after sometime and with more help from experienced FM's and more gyann baba things would be better.

pranav - please put up the total cost etc.. for the DiY project. This will encourage folks who are looking for DiY & good sound to pick up the shovel and get to work :))

regards,
mpw
 
@pranav - Impressive work! Very impressive.

Wish I had the skills to try something similar. Well my dad's an engineer so let me see if I can get him to do something.
 
@pranav - Impressive work! Very impressive.

Wish I had the skills to try something similar. Well my dad's an engineer so let me see if I can get him to do something.
================================================

daddy's boy musicbee :))

The term DiY will get a new meaning DiD ( Do it dad )

:lol:

regards,
mpw
 
Yes, the fostex speaker is having more or less the same speaker parameters. I believe direct substitution worked well in this case.
I did experiment with damping a little, but there was little difference, and the original damping conditions sounded the best. As far as my ear can tell, Zakir Hussain's Tabla hasn't sounded crispier and more blissful to me :)
The low frequency lift is perfect (for my ear). There is little distortion that i can hear in the lows, but that is also at high decibel levels. The low frequencies at low volumes is breathtaking!

I know exactly what standing waves would sound like or feel like. In my previous projects, this problem was evident and i dont seem to get that feeling in these speakers.

I still have to do the port length determination, could you please tell me how i should proceed for doing that ?
Thanks :)

Its great that you could find a substitute driver for the Fostex and also the low frequency is good with only a marginal distortion. I have never built a TQWT type TL enclosure and hence do not have any experience in this design. Since you are mass-loading the line you can try using 10% to 20% of the cross-section area for the port vis-a-vis the cros-section area of the line as a starting point. Also do not have the port too long else it will behave line a vented enclosure. If the damping is increased below the woofer then it would behave like an Aperiodic enclosure too. If experimentation is easy then you can try many things with your first design and finally arrive at the correct design for your drivers.
 
Its great that you could find a substitute driver for the Fostex and also the low frequency is good with only a marginal distortion. I have never built a TQWT type TL enclosure and hence do not have any experience in this design. Since you are mass-loading the line you can try using 10% to 20% of the cross-section area for the port vis-a-vis the cros-section area of the line as a starting point. Also do not have the port too long else it will behave line a vented enclosure. If the damping is increased below the woofer then it would behave like an Aperiodic enclosure too. If experimentation is easy then you can try many things with your first design and finally arrive at the correct design for your drivers.

Thanks i will play around with the port length and finalize soon ! As off now, it sounds good even with just a hole without a port ! :)
 
Don't u think the xover is too high at 3300hz. Can u set it lower and experiment.
Our FM Hari Iyer is also into TL speakers maybe he can guide you further.

Rgds
Mpw

Hi,
sorry, i kind of skipped this post :/
The main deciding factor on the crossover frequency was the availability of the capacitors. I was only to procure certain values. If you calculate using the usual formula's, there is a high probability of you calculating a value that is not commercially available.
I had to choose my crossover frequency keeping in mind the values available !
:)
 
I missed this thread! Was away to Ahmedabad for a couple of days .....

Fantastic stuff @ DIY. An invitation to come over to my place and have a peek at Hari's Linear Tranmission Line speakers. Maybe, you could pick up some fine-tuning clues from it. It has amazing mids with extended tight bass virtually attached to the lower mids ..... Music surely sounds far more relishing and involving .... the TL route.

Delhi surely is gradually adding on TL numbers ....
You
Me
Malvai in Gurgaon

You ... since, you would end up making a pair for yourself after you give these off to your friend :)
 
I missed this thread! Was away to Ahmedabad for a couple of days .....

Fantastic stuff @ DIY. An invitation to come over to my place and have a peek at Hari's Linear Tranmission Line speakers. Maybe, you could pick up some fine-tuning clues from it. It has amazing mids with extended tight bass virtually attached to the lower mids ..... Music surely sounds far more relishing and involving .... the TL route.

Delhi surely is gradually adding on TL numbers ....
You
Me
Malvai in Gurgaon

You ... since, you would end up making a pair for yourself after you give these off to your friend :)

Yes, i will surely try and visit soon ! :)
The TL route is a rather undiscovered one, hope people experiment more with this technique.
and surely, transmission line(ers) are just superb, will consider for my next build ! :)

BTW, i have heard a lot about your build, kindly link me to the thread ? was somehow unable to find it ! :)
 
Pranav,
I salute your passion, courage to start such a speaker and get it done to your satisfaction.
Bravo.
Way to go my friend.
You are inspiration for me.

Thinking, designing, making a speaker is so captivating and mostly rewarding.
You are one of those perfect examples.
 
Order your Rega Turntables & Amplifiers from HiFiMART.com - India's reputed online dealer.
Back
Top