New joinee in DIY Arena

[TapasDas1980]

Would this work for you?

Thanks a lot. I completely forgot about their Sound damping Tapes. I have seen this site a month ago. I will go there on Monday and will check.

 

[kaushik]

Tapas the industrial market after SP road PC mart has many damping materials ...
As for the crossover select suitable design (suri is the guy for this) ,

some good coils you can import from EBAY ,ask seller "Audio Grade" in the link to combine ship all coils ,he has fix shipping@12$ multiple items
COILTRONICS Radial Inductor .56mH, 0.2?, 5a Audio x 2 - eBay (item 330449549983 end time Nov-04-10 18:09:47 PDT)
manage Caps/resistance locally..

however ebay ordering is lil expensive but quality is good.:indifferent14:

 

[TapasDas1980]

Here the price list for Eminence Crossovers available in chennai.


S.NO MODEL NO HZ UNIT PRICE RS.
1 EMINENCE PX2-3K5 CROSSOVER 3500 4000.00
2 EMINENCE PXB2-3K5 CROSSOVER 3500 1200.00
3 EMINENCE PXB2-5KO CROSSOVER 5000 2000.00
4 EMINENCE PXB2-2K5CX CROSSOVER 2500 1750.00
5 EMINENCE S-3904 CROSSOVER 1600 2700.00



Please suggest me which one I should use for my Bolton Full ranger with a woofer and which shall I use for my previous woofer and tweeter setup.

Thanks in advance.

I am ready to order these if they work fine with my Bolton Full ranger and Dainty Woofer combo. Please let me know which model to order....

Suri sir, I am sorry but I understood the theory of your earlier post but not co relate that with these models. :-(

Help sir....

 

[TapasDas1980]

S.NO MODEL NO HZ UNIT PRICE RS.
1 EMINENCE PX2-3K5 CROSSOVER 3500 4000.00
2 EMINENCE PXB2-3K5 CROSSOVER 3500 1200.00
3 EMINENCE PXB2-5KO CROSSOVER 5000 2000.00
4 EMINENCE PXB2-2K5CX CROSSOVER 2500 1750.00
5 EMINENCE S-3904 CROSSOVER 1600 2700.00


Please let me know which model I should use for my Boltom Full ranger and Dainty 8 ohm 8" 80 Watt Dainty woofer.

Or whether I can use locally available Philips crossovers. I do not have th specification though. They are around 1K range I believe.

 

[t.antony]

There is no guarantee that those ready made options work for you, I suggest you to measure the TS parameters of your drivers using the method described in this thread and post it here.

Regds...

 

[TapasDas1980]

Hi Antony,

I have gone through the link you had posted and subsequent links.

The problem I am facing is I only have a Laptop and that has only one Headphone jack and one Line In/Microphone in jack. And they both are stereo plug ins.

Hence I am not able to understand how would I able to check TS parameters for my drivers.

Kindly help...

Thanks in advance.

 

[suri]

There is no guarantee that those ready made options work for you, I suggest you to measure the TS parameters of your drivers using the method described in this thread and post it here.

Regds...

@ t.antony -

you ask that TapasDas1980 - should measure the TS parameters of the Bolton and dainty -

and post them here -

so that you will run them through WinSD (or some such software) -

and suggest a cutting-edge solution to the project?

well, great minds have applied their resources to such exercises -

and it is known that -

this exercise is best left to the domain of perfectionists - who have a "birds-eye" view of "WHAT NOT TO DO" ( while measuring the TS parameters of various available drivers).

naive to think that the proletariat has easy access to (exact) measurements and design (thereof) of superb loudspeakers based on these -

given that - OOPS! - you would have been one of the foremost designers of (desirable) loudspeakers (with a laptop and a 100 ohm resistor)

NO-

it is not so simple as that -

far better if the OT picks up a researched design (say, by zaph audio) and works around it.

and you know what? - if you wish - i will send you those drivers (bolton and dainty - from SP road) -

i would like to see you measure the parameters (exactly or in-exactly) - post them here on this forum - and then design a loudspeaker based on those inferences- (let me remind you that "Loudspeaker design is a ' BLACK ART' )

I'll wager - that you would not know how.:indifferent14:

 

[TapasDas1980]

:-(

I think again I am back to square one.

Friends, please keep in mind that I am new to this arena and trying to get my speakers up through which I am not expecting DIVINE sound but earthly sound which should not be sound like a Fish Market..... hyeah:

Suri,

Could you please let me know, which cross overs shall I order from those available Eminence list? Or is there something I can use from SP Road? I think few shops still has some stocks of Philips cross overs, but no idea about their technical no how's

Waiting eagerly for suggestions........

 

[suri]

:-(

I think again I am back to square one.

Friends, please keep in mind that I am new to this arena and trying to get my speakers up through which I am not expecting DIVINE sound but earthly sound which should not be sound like a Fish Market..... hyeah:

Suri,

Could you please let me know, which cross overs shall I order from those available Eminence list? Or is there something I can use from SP Road? I think few shops still has some stocks of Philips cross overs, but no idea about their technical no how's

Waiting eagerly for suggestions........

no -

TapasDas1980 -

i will sponsor the bolton woofer and dainty tweeter -

t.antony will design the cabinet after measuring the TS parameters of those drivers -

you can then make them according to t.antony's design - (which will include cross-over).

after that - you will be in square heaven!

relax - like the yoga experts do - perfection cannot be a hurried thing.

 

[t.antony]

Heh Heh... I see that someone already "appointed" me for designing cabinets for this project! Sensing a lot of "BLACK ART" in this thread lately :lol:

Tapas,
You will be able to use the headphone and line in terminals if there is no internal loop back within the sound card. You can verify this with Arta installed - it's explained well in Zobsky's blog. If needed, you can take my cable for measurements. Send me a PM

Regds...

 

[suri]

Heh Heh... I see that someone already "appointed" me for designing cabinets for this project! Sensing a lot of "BLACK ART" in this thread lately :lol:

Tapas,
You will be able to use the headphone and line in terminals if there is no internal loop back within the sound card. You can verify this with Arta installed - it's explained well in Zobsky's blog. If needed, you can take my cable for measurements. Send me a PM

Regds...

t.antony - since your thesis is that anyone with a laptop/pc and a sound-card (and 100 ohm resistor) is within striking range of making a "superb" loudspeaker -
(like, after getting in-exact ts parameters and using cheap software to design
"path-breaking" rectangular monkey coffin boxes)-

well, then post here your rig/method of measuring Vas (equivalent air compliance) of the phillips 8" woofer you said you measured - (i cannot believe that you made rigid boxes to measure Vas of those drivers!)
http://www.hifivision.com/diy/12792-ts-parameters-philips-8inch.html.

do not bother about personal messages - post in open forum- actual pictures of the rig that you used to measure Vas.

and again -

what is this? post no. 14 is yours - BLACK MAGIC perhaps? - perhaps, a design optimised after careful (in-exact) measurement of TS parameters

http://www.hifivision.com/diy/10444-another-plan-open-baffles-2.html

when i state that loudspeaker design is a "black art" -

i absolutely mean that it is not the province of "people who cannot see into the depths below the surface".

and here - tyro -

listen to this -

do not seek to protect yourself with personal messages to the OT and others-

redeem yourself as the keeper of the "black art of loudspeaker thiel-small parameter measurement" in open forum.

regds -

p.s. consider this as a friendly "touche" - and you are welcome to say "pas de touche" -

but on open forum

 

[t.antony]

Suri,

If I must say pas de touch...:indifferent14:

t.antony - since your thesis is that anyone with a laptop/pc and a sound-card (and 100 ohm resistor) is within striking range of making a "superb" loudspeaker -
(like, after getting in-exact ts parameters and using cheap software to design
"path-breaking" rectangular monkey coffin boxes)-

I was misquoted here - this is what I had posted before...

"Measuring TS parameters and simulating in a software like Winisd is a proven and scientific method for getting best results for any driver. Driver behavior complies with the laws of Physics and software simulations are close to real-life scenarios."

"These parameters define the electrical, mechanical and acoustical characteristics associated with the driver. Most enclosures contain an air column that has certain mechanical and acoustical characteristics provided by the shape and size of enclosure. When TS parameters are known, the behavior of the driver in such an enclosure can be predicted. In short TS params are instrumental in almost every aspect of speaker design: from choosing the type and size of enclosure that suits the driver, designing a crossover and predicting the frequency response."

Does this mean the outcome will be superb? No... Loudspeaker is a transducer, it converts electrical energy to mechanical and acoustical energy, physics rule here - you cannot compare the capabilities a Bolton with a Scanspeak. The software like Speaker Workshop or Winisd will do the number crunching for you to arrive at an enclosure that makes the driver work optimally. What I have indicated regarding TS params is not my " thesis", it's the information available in public domain. Based on the TS params there are few rules of thumb that can give indications on the type of enclosure that suits the driver best. So please don't presume that my intention is to give any "cutting edge" design based on a software simulation. Anyone with a pc or laptop running Windows will be able to do it themselves if they are having the TS parms and follow the help file of the software of choice.

FYI - The theory behind the resistor method is indicated in this link Thiele/Small - Wikipedia, the free encyclopedia(see the first and last paragraph under Measurement techniques).

well, then post here your rig/method of measuring Vas (equivalent air compliance) of the Phillips 8" woofer you said you measured - (i cannot believe that you made rigid boxes to measure Vas of those drivers!)
http://www.hifivision.com/diy/12792-...ips-8inch.html.
do not bother about personal messages - post in open forum- actual pictures of the rig that you used to measure Vas.

Vas can be measured by adding mass to the driver cone and then measuring the new impedance characteristics. It's already mentioned in the Rod Elliot link you have posted before - (see measuring Vas - Method 2). Also if you notice the figure 2 in that page, the software replaces the oscillator, power amp is replaced by the headphone output and volt meter is replaced by the sound card line in channels.

Here is a pic of how to add mass to the driver diaphragm using 5 rupee coins. I used 5 rupee coins since they are not ferromagnetic and the weight is standard (9gm)

And my measurement "rig". The black jack goes to the headphone out and yellow to the line in of the sound card.

what is this? post no. 14 is yours - BLACK MAGIC perhaps? - perhaps, a design optimised after careful (in-exact) measurement of TS parameters
http://www.hifivision.com/diy/10444-...baffles-2.html

That was an experimental baffle I made to compare an N profile dipole with an H profile one. It's a diy experiment and no Black Magic.

N profile - There is very little information on this alignment and most are in German forums, so thought of building one to see for myself. Axel Ridtahler holds a patent for this. Here is a diy kit with some info - RiPole Subwoofer.

H profile - This is well documented by Linkwitz (Dipole protos) and Martin J King (OB Theory), both use different approaches though.

Measuring the response of these experimental baffles require more hardware and other specialized "rigs". This is what I use.

when i state that loudspeaker design is a "black art" -
i absolutely mean that it is not the province of "people who cannot see into the depths below the surface".
and here - tyro -
listen to this -
do not seek to protect yourself with personal messages to the OT and others-
redeem yourself as the keeper of the "black art of loudspeaker thiel-small parameter measurement" in open forum.
regds -
p.s. consider this as a friendly "touche" - and you are welcome to say "pas de touche" -

but on open forum

And finally - a pic of my current setup. Using professional 15" LF drivers with Philips full range bi-amped using Xonar D2X and Foobar2000 with active xo plugin. The LF drivers are powered by a vintage Sansui AU 909 amp and the Philips by a DIY mosfet kit amp. There is no black magic here either. The thought process behind this design(or rather I say contraption) is very similar to the OB article by Rudolf Finke - check the last link in the downloads section(How open baffles work - from point sources to small drivers in big baffles to big drivers in small baffle). This design, though sounding nice, due to the accident prone nature - will be giving way to an H profile and narrow baffle in the near future.

I asseverate that I have no interest in seeking redemption for being a "keeper of the black art of loudspeaker thiel-small parameter measurement" as this info is already there in public domain. And yes, I consider myself very much as a neophyte in speaker building.

It's also a bit revealing that you, despite having built few good looking and sounding loudspeakers holds so little information about the Thiele Small parameters and the science behind speaker building. - so here - virtuoso(?) - may I suggest to rely less on thesaurus and start a new chapter on the science of speaker building? If needed, I will gladly sponsor a copy of Vance Dickason's Loudspeaker Design Cookbook.

P.S: Take the last paragraph with a pinch of salt and good friendly spirit of touch

Regds...

 

[suri]

I asseverate

from today -

i will follow your direction!

and believe what you have to say.

regds

suri

regarding the science that pushes the cart of loudspeaker design -

"i do not believe what the mortal man has to say"

after all , if one believes all the (finite) knowlegde available - regarding loudspeaker design (based on TS parameter) - one will confine oneself.

and further - if you must design your loudspeakers (rigidly) on these foundations - well, then they must be perfectionist and exact-

for example -

i have followed -http://www.zaphaudio.com/

and have constructed some of them (did not like them(http://www.zaphaudio.com)


and here - i posit - that

loudspeaker design is less a science - and more an art.

at the end of the day - Thiele-Small parameters (of the drivers used) can only tell you "WHAT NOT TO DO"-

and will never tell one - "what to do"

and so-

while i get all my designs validated (i pay for these) - i probably pay for not making a mistake -

i select and buy drivers that have consistently reproducible (by manufacture) variables {including then, TS parameters) .

and i pay for professionally designed cross-overs based on the selected drivers and the (dimensions of the cabinet that i will design)

and i asseverate that i am not involved in the (in-exact) science of this persuasion -

but (am involved) in the art, and the finality of it (the reproduction of the original audio event)

so, why do you assume that i must master the art of measurement of TS parameters of transducers - and apply (freeware, software, proprietary software) to arrive at the design of a (rectangular box) loudspeaker? - the design may not offend - may conform - but may not excite the senses.

and here -

i asseverate that -

i will pay professionals (who know their field) to select the drivers and associated electronics for the designs i make - (and to advise me if i go wrong)

i would not regard myself as a jack-of-all-trades -

and make myself a jack-ass

Touch

and if you really believe that (in-exact) measurements of TS parameters of individual drivers and the application of (free) software is enough to produce superb loudspeakers -

then, it should be a simple task to produce a clone of the wilsons or sonus faber using scanspeak drivers-

no,

-loudspeaker design is (really) a "black" art -

and you and i are at the opposite ends of it

and-

apart from that "cookbook" -

please read this -

http://webcache.googleusercontent.c...ing&cd=2&hl=en&ct=clnk&gl=in&client=firefox-a..

if the making of a transducer is a black art - the making of a cabinet to house disparate drivers and make them work as one is also a black art

 

[suri]

and t.antony -

before we both go off on tangents with unnecessary advice to each other (eg., stop reading thesaurus - start writing a book on the science of speaker building, please allow me to buy a book for you)-

let me state how i go about designing a loudspeaker-

- the upcoming design is usually based on the last completed design - usually with the goal of correcting defects-

first, i select the drivers - i started with peerless - but now it is always scanspeak - and now it is always a two-way - and i like a tweeter that can be crossed over as low as possible-

second, i pen the approximate way i want the front baffle to look - with approximate dimensions-

also with approximations of mounting position of the two drivers (this is an art by itself .

third, i start the process of consultation with techs at madisound- who in turn measure the TS parameters of the actual chosen drivers- using http://www.proaudioreview.com/article/1840 (which usually match the published TS parameters of those drivers- is what they say).

following this,they use LEAP software

Leap Crossover Design Service from Madisound Speaker Components, Inc.

to design the cross-over for the cabinet and baffle dimensions of the speaker in the making. (at times the cabinet dimensions are changed - but not by much recently)

the assembled cross-overs and drivers are delivered by fedex in about 3 weeks time-

during this work - the "black art" of speaker cabinet construction has already started-

and emphasis is usually on the tweeter housing and effective de-coupling from the mid-woofer housing (this again is an art not mentioned in the usual cook-books.

care is taken not to deviate from the volume and cabinet dimensions by more than 2% (and this is the only time that i actually sit with the carpenter and take measurements - and use a hand held calculator to, say, calculate the air column volume {adding 3% if the air-column takes a right angle bend}) .

let me tell you a little secret - not mentioned in that cookbook -

"it is very important that the air column behind a driver should be about 3 times the cone size in a straight line before it makes a bend - eg., for an 8'' driver (8" cone) the air column must extend backwards in a straight line for 24" before it bends/meets the back wall.

the cross-overs are always mounted in a separate housing outside the loudspeaker (in the base).

from starting a design to completed loudspeaker takes 6 months-

measurements - they used to be made - with (actually) a good microphone -
and the resulting graph was frightening to look at - and nothing like the simulations sent by madisound - apparently, our testing technique and environment was lacking.

let me say this - it is in art of making speakers that i want to be -
if i had to be in the science of it, it would have to be exact, and i think that i do not have the resources to put up an anechoic chamber and buy dedicated (expensive) software to design the cross-overs-

it would be like reading a surgery step-by-step manual and then performing an appendicectomy operation - i would probably end up doing an autopsy!:lol:

 

[suri]

@t.antony -

all that TapasDas1980 wanted to do was -

use a bolton woofer and dainty tweeter with a ready made cross-over and get started on the DIY route.

asking him to measure the TS parameters of those drivers - and then design a suitable crossover - source the parts - put them together - a bit much, don't you think?.

honestly, i think you should offer to do it for him.

 

[TapasDas1980]

Hats off to both you guys.....

Thats why I like this forum so much.

Antony, although I like your way of building Speaker set, but some times newbie like me, this procedures may keep me behind... :sad:

Now I would like to say some thing.

Do you guys really think that if I use good quality cross overs along with Bolton Full rangers and Dainty Woofers, which are not at all respected for their quality. Also you guys need to keep in mind that I have already made the Boxes for my drivers. And in Gobble's language they are just like Coffins :lol: And my wife is already trying to pull them up to build shoe rack.....

But I am still holding my forte without loosing hope.

 

[t.antony]

Thanks Suri, for the time and thoughts.

I see, there is nothing more assuring to one as thoughts of conviction that scratch the gray matter and experiences based on notions of a personal nature.

after all , if one believes all the (finite) knowlegde available - regarding loudspeaker design (based on TS parameter) - one will confine oneself.
and further - if you must design your loudspeakers (rigidly) on these foundations - well, then they must be perfectionist and exact-
for example -
i have followed -http://www.zaphaudio.com/
and have constructed some of them (did not like them(Zaph|Audio)

Perfectionism ... I don't buy it, no mortal is perfect, so how can one make anything perfect?

at the end of the day - Thiele-Small parameters (of the drivers used) can only tell you "WHAT NOT TO DO"-
and will never tell one - "what to do"

TS params did not tell what not to do or what to do - that's up to the designer's discretion - there are some methods and math that will evaluate the performance of the driver in the designed enclosure (real or virtual). It's up to the designer to decide whether to take this into account or not.

"it is very important that the air column behind a driver should be about 3 times the cone size in a straight line before it makes a bend - eg., for an 8'' driver (8" cone) the air column must extend backwards in a straight line for 24" before it bends/meets the back wall."

Interesting observation, this depth is sufficient to create quarter wave resonances in the sensitive lower mid range region. Assuming minimum width for front baffle, the cross section area becomes greater than 3xSd -which is considered good for extending the low frequency performance - Remember reading that Bob Brines uses 4x cross section area in some of his designs.

honestly, i think you should offer to do it for him.

This is Tapas's project - I cannot design, build, and test a system for him nor I can test his driver's TS parameters, why not help him do it by himself, and there are many people in this forum who can give valuable tips from their experience. So better keep it that way. I will present the projects I have designed and built on this forum, along with measured data. But that will be the subject of another thread...

@ Tapas,
Regarding xovers, you could try the approach mentioned in this thread - (http://www.hifivision.com/diy/10444-another-plan-open-baffles-4.html#post153967), check the posts 32 & 34, it might work for you. Suri should be able to guide on the cabinet dimensions. There are some rules of thumb that could give good responses - as he has explained before. So if resizing your cabinet to a suitable dimension is possible, you can try it as well.

Regds...

 

[suri]

Perfectionism ... I don't buy it, no mortal is perfect, so how can one make anything perfect?

imperfect mortals have made perfect things -

1. i do not see anything less than perfect with Zeiss and Leica optical products- they, sometimes, seem to go beyond perfection as we define it

2. the music of wolfgang amadeus mozart - ajay124 has posted a video where the court composer describes mozart's music ("It was like i had heard the voice of god")

3.the honda acura NSX (the peerless ayrton senna helped in the design) has been described as the perfect sportscar (though some people on this forum like diesel cars)

4. some of the speyside single malts are no less than perfect (until i learn better from ajay124)

5. what about Kissan tomato ketchup - seems to be perfect?

6. a rolex watch - if that is not made by man to perfection, what is? (have you seen the inside of the case cover?)

7.the hydrogen bomb? - that is so close to absolute perfection (when you see a second sun- be sure that one of our ahmedinijads of the world has done a perfect thing!)

8. and what about the world-wide-web? - that is not perfection?

9. and what about this - L115A3 Long Range Rifle - British Army Website - perfect - and only the most capable mortal can extract absolute performance from equipment as perfect as this.

10. stainless steel - that is so perfect! - especially austenitic steel -
Austenite - Wikipedia, the free encyclopedia

11. roget's thesaurus

i think i could quote another 100 examples -

yes - imperfect mortals are able to make perfect objects of desire.

but do you not think that-

everyone should strive for perfection? - doing his/her best? -

 

[TapasDas1980]

Thanks Suri, for the time and thoughts.

I see, there is nothing more assuring to one as thoughts of conviction that scratch the gray matter and experiences based on notions of a personal nature.


Perfectionism ... I don't buy it, no mortal is perfect, so how can one make anything perfect?

TS params did not tell what not to do or what to do - that's up to the designer's discretion - there are some methods and math that will evaluate the performance of the driver in the designed enclosure (real or virtual). It's up to the designer to decide whether to take this into account or not.

Interesting observation, this depth is sufficient to create quarter wave resonances in the sensitive lower mid range region. Assuming minimum width for front baffle, the cross section area becomes greater than 3xSd -which is considered good for extending the low frequency performance - Remember reading that Bob Brines uses 4x cross section area in some of his designs.

This is Tapas's project - I cannot design, build, and test a system for him nor I can test his driver's TS parameters, why not help him do it by himself, and there are many people in this forum who can give valuable tips from their experience. So better keep it that way. I will present the projects I have designed and built on this forum, along with measured data. But that will be the subject of another thread...

@ Tapas,
Regarding xovers, you could try the approach mentioned in this thread - (http://www.hifivision.com/diy/10444-another-plan-open-baffles-4.html#post153967), check the posts 32 & 34, it might work for you. Suri should be able to guide on the cabinet dimensions. There are some rules of thumb that could give good responses - as he has explained before. So if resizing your cabinet to a suitable dimension is possible, you can try it as well.

Regds...

Thanks Antony,

I have gone though the posts and they are about Ahuja cross overs. I respect your knowledge and experience but don't you think I should not use them as they are mainly for PA drivers?

Also, in all the xovers, both the coils are sitting side by side and as a result they will always keep on talking to each other cause of the Polarity factor. Don't you think that a bad factor as far as home Audio quality is concern?

 

[TapasDas1980]

Friends,

After searching for weeks, finally I was able to find a shop in SP Road where you can find good quality Felt material and Fiber Glass wool for your Audio projects.

The owner is very knowledge about their usage and he told that he normally sell them to many Theaters in and around Bangalore.

Surprisingly both items seems to be costly but Fiber Glass wools are even costlier as one can not get them loose. They have to purchase one full bag and total cost would be around 2.5K.

I think a full bag can be used for 2-3 pares of Tower speaker, hence again I need search for other's who will be willing to share with me.

Felt Material cost is some what OK. He sell them in Rs/Kg basis and its in between 250-550/Kg.

His name is Ameer Ali K Mody.
Shop : Everest Industrial Stores.
19/4, Malavali rama Rao Lane, S.J.P Road Cross.
Ph: 41324786