An evening spent 'tweaking' Avidyarthy's ATL Speakers

[ravi_d]

The PMC is not a exo-linear design but a classic straight line TL. The driver is off-set from the closed end. The line may be tuned some what higher than the resonating frequency of the driver to reduce line length. The terminus area in the open-end is larger than the line area in the closed-end.

I think ATL is a buzzword and not a technology on its own. PMC call their version of TL as ATL and use it as a trademark to promote their speakers and I think all their models for past 20+ years are only TL's.

The damping of the line is done by an egg-foam type of material and some mid-range emerged from the terminus when i heard Bagwans PMCs.

In my tower ATLs the mid-range is completely damped and only low frequency lower than the 3rd harmonic can be felt from the terminus.

Only an apples to apples blind test can tell which sounds better.

May be you need to listen to them once more properly to see if the PMC ATL is working to as what they claim.
BTW they claim they manufacture their own foam which absorbs the upper bass and higher frequencies that radiate from the rear of the main driver and the lowest frequencies remain in phase and emerge from the large vent at the end of the line. And they have been calling it as ATL and selling their products on that whole idea.

The ATL (Advance Transmission Line Speakers) from PMC - YouTube

What material you use to dampen the transmission line?

Some positive points:
- they sound the same/lively at lower volumes and higher volumes.
- they are efficient. On one of the Delhi hifi meets the bigger stand mount TB2i worked well even with Lyrita valve amp putting 1.5 watts/ch (not sure if its 3W/ch)
- my model seems to work well closer to wall and has provision for wall mounting brackets.
- the bass seem to go deeper with out any exaggeration on lower frequencies and I don't seem to miss anything

 

[avidyarthy]

"Some positive points:
- they sound the same/lively at lower volumes and higher volumes.
- my model seems to work well closer to wall and has provision for wall mounting brackets.
- the bass seem to go deeper with out any exaggeration on lower frequencies and I don't seem to miss anything"

^^^ Quite the same in my FS speakers too ...........

 

[ravi_d]

"Some positive points:
- they sound the same/lively at lower volumes and higher volumes.
- my model seems to work well closer to wall and has provision for wall mounting brackets.
- the bass seem to go deeper with out any exaggeration on lower frequencies and I don't seem to miss anything"

^^^ Quite the same in my FS speakers too ...........

I mentioned the last point because the DB1i's are barely bigger (290 x 155 x 234 mm) than your JBL control 1's and hence the frequency spectrum produced by them is outstanding.
I think the bass performance and sounding lively at lower volumes are typical characters of a TL design.

BTW what is the pricing of your floor stander?

Later at some point I would like to move to a bigger stand mount/ floor stander TL's with bigger 6.5" woofer preferably from PMC.

 

[Hari Iyer]

I think ATL is a buzzword and not a technology on its own. PMC call their version of TL as ATL and use it as a trademark to promote their speakers and I think all their models for past 20+ years are only TL's.


May be you need to listen to them once more properly to see if the PMC ATL is working to as what they claim.
BTW they claim they manufacture their own foam which absorbs the upper bass and higher frequencies that radiate from the rear of the main driver and the lowest frequencies remain in phase and emerge from the large vent at the end of the line. And they have been calling it as ATL and selling their products on that whole idea.

The ATL (Advance Transmission Line Speakers) from PMC - YouTube

What material you use to dampen the transmission line?

Some positive points:
- they sound the same/lively at lower volumes and higher volumes.
- they are efficient. On one of the Delhi hifi meets the bigger stand mount TB2i worked well even with Lyrita valve amp putting 1.5 watts/ch (not sure if its 3W/ch)
- my model seems to work well closer to wall and has provision for wall mounting brackets.
- the bass seem to go deeper with out any exaggeration on lower frequencies and I don't seem to miss anything

I have auditioned the above PMC in the Mumbai Hi-Fi vision meet in the year 2011 and my comments are based on that. As per my knowledge that i know, a TL only uses a fibrous material (wool, fiber glass, dacron etc.) as the density & weight of the fiber is a very important parameter for the calculation of the enclosure. This also affects the way a TL will sound. Please let me know if you have any material about how to calculate a TL enclosure without a fibrous material then it will be interesting. I am not sure if this egg foam material is some kind of a marketing hype as no classic text exist about its benefits. The video talks about the foam material getting compressed at higher SPLs. The velocity of the air in the Line is reduced due to the fibrous material only damping the frequencies above the 3rd harmonic. When i closely examined the PMC in the terminus area, i could actually hear the mid-range which was not completely damped by the egg-foam as claimed. I am not sure if this is a quality issue for that piece as foam manufacturing can vary over production runs.

 

[avidyarthy]

Had a good long session today, with Ashish (of Lakozy-Delhi), anm and cybervinay being guests of honour.

Rock, Instrumental and Vocals were tried out ... CDs, MP3 disc and USB .... Marantz as source.

Let the three give their own opinions of my simple set-up. Any of their suggestions to further improve on the current would be highly appreciated.

BTW, forgot to ask anm ...... is the Thiel 1.6 up for sale?

 

[ashishkesarwani]

Had a chance to audition Avidyarthy's setup today, the sound was pleasantly warm and pleasing to ears. I played few of my favourite tracks in WAV format through a Pen Drive connected to the Marantz CD player and overall detailing was good with a good sound staging. The system was very transparent and it was evident when a MP3 cd was played on it. The speakers had descent highs/lows, but during certain portion of Music the Mids lacked a bit of detail and this is where Vinay as well as Anant also agree with me. I will leave it on to Vinay and Anant to explain their experience. But overall its a very good effort.

 

[dillihifi]

bhai log mere ko bhi bula lete hyeah:

 

[anm]

^ sorry I was not planning, but Vinay asked so I tagged along.
Setup - I loved the setup as avid has kept it to a bare minimum. I think speakers have lot of potential. Could ground firing port be the reason for some mids lacking detail?

 

[Hari Iyer]

Had a good long session today, with Ashish (of Lakozy-Delhi), anm and cybervinay being guests of honour.

Rock, Instrumental and Vocals were tried out ... CDs, MP3 disc and USB .... Marantz as source.

Let the three give their own opinions of my simple set-up. Any of their suggestions to further improve on the current would be highly appreciated.

BTW, forgot to ask anm ...... is the Thiel 1.6 up for sale?

I have now completed my study on the Harmonic Balance concept and have implemented in my own classic TL and is currently under test. The sound quality is very pleasant and even more balanced than before. The mid-range now blends even more seamlessly with the lows & highs with the harmonics sounding very balanced i would say.

I will implement this idea fully in my next project onwards as i have also completed the simulation and fine tuning aspect for the same. If required i can upgrade your speakers too with the modifications when i plan to be at New Delhi during winter vacations along with family. It certainly will be worth the effort.

Cheers,

 

[Hari Iyer]

^ sorry I was not planning, but Vinay asked so I tagged along.
Setup - I loved the setup as avid has kept it to a bare minimum. I think speakers have lot of potential. Could ground firing port be the reason for some mids lacking detail?

Thanks anm for the feedback. The ground firing port was used to use the length of the line to the advantage. The mids above the 3rd harmonic are anyway damped and will not be allowed to flow through the terminus. If the mids are missing, then some modification with the damping will help by adding/ removing damping depending upon the response. Also the harmonics not being completely balanced in the entire FR could be one of the reason for mids lacking detail as minute details could be masked by other frequencies because of this. In the next version of the speakers i will be addressing this issue by implementing the harmonic balance concept which should allow minute mid-range detail to be heard with precision.

 

[srinisundar]

Had a chance to audition Avidyarthy's setup today, the sound was pleasantly warm and pleasing to ears. I played few of my favourite tracks in WAV format through a Pen Drive connected to the Marantz CD player and overall detailing was good with a good sound staging. The system was very transparent and it was evident when a MP3 cd was played on it. The speakers had descent highs/lows, but during certain portion of Music the Mids lacked a bit of detail and this is where Vinay as well as Anant also agree with me. I will leave it on to Vinay and Anant to explain their experience. But overall its a very good effort.

Ashish,

Thanks for small write up.

As we know you have heard and owned plenty of equipment and also your passion and profession is music..., So we need more inputs from you...Do not disappoint us

Regards

 

[srinisundar]

^ sorry I was not planning, but Vinay asked so I tagged along.
Setup - I loved the setup as avid has kept it to a bare minimum. I think speakers have lot of potential. Could ground firing port be the reason for some mids lacking detail?

This is your review Anm come on.. Any output on AVID question of selling your Thiel>> Is the ATL is so great, as an Thiel owner i also interested in hearing your inputs and thought.

 

[avidyarthy]

Just gotten back after ordering out the curtains and some cushions for the vintage sofa set in the room. All these should be put in place by Wednesday ... hopefully, the room should be more presentable and effective (SQ wise) post Wednesday.

Don't have funds available for the mandatory AC, maybe, after a few months of moolah accumulation should do it . Its freaking hot in Delhi currently!

 

[BLASTO]

Had a chance to audition Avidyarthy's setup today, the sound was pleasantly warm and pleasing to ears. I played few of my favourite tracks in WAV format through a Pen Drive connected to the Marantz CD player and overall detailing was good with a good sound staging. The system was very transparent and it was evident when a MP3 cd was played on it. The speakers had descent highs/lows, but during certain portion of Music the Mids lacked a bit of detail and this is where Vinay as well as Anant also agree with me. I will leave it on to Vinay and Anant to explain their experience. But overall its a very good effort.

Sorry, but did you try any ACDs??
Mp3 themselves do not have the midrange details..
Also compared to which speakers do these have less midrange details?


@Anm, How were vocals especially??

 

[srinisundar]

Want to know "Krypton K300TL" is making speechless who have heard... Need some brief comment by Anm / Cybervinay / Ashish has put some write-up, request some brief write-up against the similarly priced speakers and krell amp. -

Krypton K300TL is worth more than Thiel - anm you word is required here ?

 

[denom]

Want to know "Krypton K300TL" is making speechless who have heard... Need some brief comment by Anm / Cybervinay / Ashish has put some write-up, request some brief write-up against the similarly priced speakers and krell amp. -

Krypton K300TL is worth more than Thiel - anm you word is required here ?

Maybe the K300's has left the 3 of them speechless
Recovering from the after shock guys ????

Await your views on the K300's

 

[avidyarthy]

sulk: sulk: sulk: :sad: sulk: :indifferent14: .......... ..

 

[ashishkesarwani]

Sorry, but did you try any ACDs??
Mp3 themselves do not have the midrange details..
Also compared to which speakers do these have less midrange details?


@Anm, How were vocals especially??

We did play few Audio Cds, and the Pen Drive had WAV files so content was not to be blamed here. When Avidyarthy put an MP3 into the CD player then we immediately could make out the difference but he seemed to be ok with it.

 

[anm]

vocals were nice. Bass is more than in in theils IIRC (but I need to listen to the same songs that I listen to mostly). Would need second auditioning to comment further. Once curtains and all is there.

 

[srinisundar]

vocals were nice. Bass is more than in in theils IIRC (but I need to listen to the same songs that I listen to mostly). Would need second auditioning to comment further. Once curtains and all is there.

Appreciate your intial input and look forward to recieve your second round of auditioning and final comments.