An evening spent 'tweaking' Avidyarthy's ATL Speakers

[prem]

Hi anm

Hari"s speakers have a lot of potential. Its for him to decide where he wants to take his speakers. From my experience, i have realised one cannot get everything from a speaker. I only raised that question because i felt that comparison was going the wrong way.

 

[jls001]

Hari - when you design a speaker, what are your "tonality" goals, if any? Do you have a reference speaker/ sound in mind? Or, is it even a correct design goal I wonder. I am asking this based on prem's recommendations above.

I think that's a brilliant question to ask. A tough goal to achieve for the designer, though. It all boils down to setting a goal before undertaking a task. The success of the undertaking can only be gauged based on the goals thus set.

 

[Hari Iyer]

Hari - when you design a speaker, what are your "tonality" goals, if any? Do you have a reference speaker/ sound in mind? Or, is it even a correct design goal I wonder. I am asking this based on prem's recommendations above.

The below will be some of my goals,

- precisely defined imaging, particularly in the vocals and bass region
- precisely timed bass without echo or reverberant booming allowing excellent transient response and uncompressed dynamics
- Balance of the Harmonics across the audio spectrum that allow a more balanced sound which will allow details to come out clearly and preserve the timber or the tonal balance of the sound. This aspect however will require more study and research and the ATLs was the first speaker i tried to implement them.
- Coherent sound stage with zero phase-shift to allow detailing to be preserved.
-Diffraction is also studied and taken care of (look at the baffle shape & the felt material - i did not care much about the looks of the speakers if the nets are removed as 99% of the time the nets will be fixed to the speakers)
- Wide band width drivers allow for first order cross over design.
- Time alignment to allow coherent sound stage
- Take a minimalist design approach in cross-over to allow tweaking after listening test.


Usually i do a lot of simulations with the drivers, the filters and play around changing the values of the components and have an fair idea of how the FR of the driver, the filter curves will influence the speaker system. Phase curves and group delay are also studied. The impedance curves are also studied for the linear range before the design is finalized. Once mathematically the values are okay, then i decide to build them.

I usually do not give much significance to listening test as they are influenced by our listening ability, associated hardware and interconnects and of course the room where the speakers are installed and the software being played. I take a back seat hear and just listen to what the more experienced listeners or audiophiles have to say about my design. I get more kick & pleasure in the mathematics of the sound than the actual speaker sound itself. That's the reason i do not have high end hardware or speakers at my home too. I believe if a speaker is mathematically perfect then chances are they may sound well in the real time environment too and this is my goal i would say.

I have also read some one say the slogan - Speaker design is not just a 'Science' but also an 'Art'.

 

[olly42]

Krell + Krypton ATL

Congratulations Avid :clapping:

Hari speakers are looking Awesome :clapping:

 

[srinisundar]

Hi anm

I only raised that question because i felt that comparison was going the wrong way.

Just asked anm to pair with krell, since AVD indicated in another post about he may end up in selling those once he hear the ATL.. AVD could have heard how thiel sounds, so thought anm also put his views.. Still i have not settled with Power amps for my thiel thought anm input will help me to decide.

 

[BLASTO]

The speaker you auditioned at my home were not ATL but a mass-loaded classic TL and the cross-over design was also completely different than the one used for Avid's speakers. Hence my own speaker K150TL cannot be compared with Avid's K300TL as the drivers, enclosures and technology are also different though from the same manufacturer. Also i have tried to introduce a concept of Harmonic Balance to the cross-over network in Avid's ATLs which is not present in my own speakers. Hence it should be a good exercise if the Thiel and Avid's ATL are auditioned together if possible. Since i have not heard the Thiel it will not be correct for me to anyway comment on them, but i have read extensive reviews about them and am sure they would sound better than the ATLs given Thiel's expertise, R&D and team work. This comparison will help me to find flaws in my own design and help for future upgrades too.

Very few speakers have time coherence even taken in to account. It is a very good step in the right direction for you to consider it.

 

[BLASTO]

The below will be some of my goals,

- precisely defined imaging, particularly in the vocals and bass region
- precisely timed bass without echo or reverberant booming allowing excellent transient response and uncompressed dynamics
- Balance of the Harmonics across the audio spectrum that allow a more balanced sound which will allow details to come out clearly and preserve the timber or the tonal balance of the sound. This aspect however will require more study and research and the ATLs was the first speaker i tried to implement them.
- Coherent sound stage with zero phase-shift to allow detailing to be preserved.
-Diffraction is also studied and taken care of (look at the baffle shape & the felt material - i did not care much about the looks of the speakers if the nets are removed as 99% of the time the nets will be fixed to the speakers)
- Wide band width drivers allow for first order cross over design.
- Time alignment to allow coherent sound stage
- Take a minimalist design approach in cross-over to allow tweaking after listening test.


Usually i do a lot of simulations with the drivers, the filters and play around changing the values of the components and have an fair idea of how the FR of the driver, the filter curves will influence the speaker system. Phase curves and group delay are also studied. The impedance curves are also studied for the linear range before the design is finalized. Once mathematically the values are okay, then i decide to build them.

I usually do not give much significance to listening test as they are influenced by our listening ability, associated hardware and interconnects and of course the room where the speakers are installed and the software being played. I take a back seat hear and just listen to what the more experienced listeners or audiophiles have to say about my design. I get more kick & pleasure in the mathematics of the sound than the actual speaker sound itself. That's the reason i do not have high end hardware or speakers at my home too. I believe if a speaker is mathematically perfect then chances are they may sound well in the real time environment too and this is my goal i would say.

I have also read some one say the slogan - Speaker design is not just a 'Science' but also an 'Art'.

Now those are some really serious design goals. Almost every speaker designer starts with those in mind. The end product however could be completly different.
I will suggest for the second time to buy a good 2 channel amp and a dedicated CD player to test out the speakers. AVR and BDP will inly help to an extent.

 

[anm]

thiels also claim to have first order crossover and time/ phase alignment.
srini - I don't have golden ears, but will try my best to help you. I am finding NAD C375 quite good. The bass is NOT flabby as I thought earlier. I think it was because I was taking analog out from my appletv.
At 9 o clock position, it drives them fairly loud.

 

[corElement]

thiels also claim to have first order crossover and time/ phase alignment.
srini - I don't have golden ears, but will try my best to help you. I am finding NAD C375 quite good. The bass is NOT flabby as I thought earlier. I think it was because I was taking analog out from my appletv.
At 9 o clock position, it drives them fairly loud.

Haven't visited yet?

 

[anm]

not yet. Sunday I was stuck with family. Aiming for landing at his place at 30 mins notice some weekday. Of course I won't be able to carry NAD in that case. If I can pull it off in a weekend, I will carry the NAD C375 for sure.
Maybe if I get the sat off, I can invite him to my place.

 

[Hari Iyer]

Very few speakers have time coherence even taken in to account. It is a very good step in the right direction for you to consider it.

Time coherence is not rocket science if you ask me. You will need to have no phase shift acoustically or electrically to achieve that. Time alignment of the baffle to have both the woofers and tweeters to have a coincident wavefront will prevent acoustic phase shift. Using first order filter will allow zero-phase shift electrically.

Usually when you use higher order filters (second & above) the cross-over introduces phase-shift or 180 deg, 270 deg or 360 deg. But in a first order filter its 90 deg and both the woofer and tweeter phase-shift cancel each other to give a zero phase shift.

Time aligning of the baffle does not give any value add for 2nd or higher order filters because there will be not much overlap of frequency due to the steep roll-off and there is already a phase-shift introduced by the cross-over. Hence time-alignment will not help there.

 

[anm]

not yet. Sunday I was stuck with family. Aiming for landing at his place at 30 mins notice some weekday. Of course I won't be able to carry NAD in that case. If I can pull it off in a weekend, I will carry the NAD C375 for sure.
Maybe if I get the sat off, I can invite him to my place.

btw, we can plan for next sunday to be at his place together. Maybe at my place also but that would mean 2+2 hours for listening.

 

[avidyarthy]

New thing observing since yesterday ....

The speakers are kept apart by around 8', set close to the back wall (1') and with a toe-in of 60 deg. The SQ is quite the same all over the room, well, in most of it ... no sweet-spot concept! Thats new .... maybe, it might get better with more burn-in. Should have clocked 25 odd hours till now .....

 

[iaudio]

Wide sweet spot! Thats a good thing! So you are hoping it gets wider with burn in?

 

[Hari Iyer]

New thing observing since yesterday ....

The speakers are kept apart by around 8', set close to the back wall (1') and with a toe-in of 60 deg. The SQ is quite the same all over the room, well, in most of it ... no sweet-spot concept! Thats new .... maybe, it might get better with more burn-in. Should have clocked 25 odd hours till now .....

This was the result of careful design of the cross-over and using technologies like Harmonic Balance to reduce high & low Q points in the Frequency Range. The result is uncompressed dynamics having even response with no off-axis deviation in the response resulting in less hearing fatigue. The Harmonic balance concept also might be the reason for the sweet tube like amplifier sound but i will wait for CorElement to further comment about that during his next visit.

 

[avidyarthy]

Heard John Denver over the last 2 hours ...... first time on Transmission Line .... BLOWNNN AWAY!

 

[jls001]

Heard John Denver over the last 2 hours ...... first time on Transmission Line .... BLOWNNN AWAY!

That's nice to know It's good that you like your new speakers so well. All that wait and all that tension if it would sound good would now melt away into the night. And I'm sure its maker would be relieved too. Happy listening.

 

[hifiashok]

very happy for u!

 

[avidyarthy]

Having tried virtually all genres of music, and getting what I desired, tried the final 'reference point' today immediately after coming home from office. Sitar and Sarod at concert level volume levels!

Thank you, Mr. Hari Iyer ....... your speakers have crossed the 'reference point' with flying colours. It is, as if Pandit Ravi Shankar and Ustad Amjad Ali Khan are sitting in front of me ... and 'exclusively' playing for me!

The playing room is still way below what it should be ... devoid of carpets and curtains, unused furniture still lying around in haphazard fashion. So, the end result would exceed the already excellent SQ, no doubt. But, that has to wait till wifey is back.

The technical guy at Pro-fx from whom I bought the Norstone speaker cable too called up to find whether the installation had been completed. He was aware of the prowess of Transmission Line speaker and is keen to come over for a hear. ... would get a shock if he tries comparing it to his Mordaunt Shorts ... that too in an un-treated bare room, nowhere to the one he gives his demos.

My schedule till the 30th June (date when wifey is back) would be to hit the listening area by 6.30 PM and get up for dinner (which I have to prepare myself ) at 10.30 PM ..... at concert level volumes . After 30th June, it would be seemingly difficult ... wifey and kids would throw tantrums! However, I would use strong arm tactics to manage till 31st July (head-banging new job begins from 1st August) .... after which ... only possibility would be some stretches during weekends. Wifey is surely going to curse you to oblivion. :indifferent14:

 

[avidyarthy]

hifiashok is paying a surprise visit now ..............