My Drivers..i Finally got them!

Ronnie22 schrieb:

A few more questions, Sachi :-) Where did you get those wires? Are they available freely (if I want to procure them in Chennai). Any idea about the 4mm or 6mm wires from Finolex for the internal wiring?

Yeah they should be freely available.
They were bought from a cables only shop on SP road.

Ronnie22 schrieb:

How did the carpenter say he would make the curved edges for the cabinet......if i need to explain that to local carpenter here

He did not say but i'll find out and let you know.

Ronnie22 schrieb:

Where did you get glass wool from? Would the stuffing found in pillows do as well?

I bought the glass wool from Mr.Arasu.
paid about 10 bucks a square feet. I bought 20 square feet from him and he gave me 8/9 square feet for free(they were used in a experimental speaker and were around a month or so old and were used for linig the inner cabinet).

Regarding stuffing, i think glass wool is the best bet (but careful while handling them).
apparently they come in different grades and thickness.
But if u can land that polyfill type of filling i say go for it. Anything else is a compromise and glass woll wwould deliver the best damping effect.
What people in India generally use are DAcron, foam and racron.they are not as effective as glass wool and racron/dacron are pretty expensive.

Ronnie22 schrieb:

What screws did you use on the cabinet walls? You were referring to some round machine screws? Any idea what they are called in a hardware store?

Yes, they are called machine screws in hardware shops too.i'll post a picture later if u still have doubts.

Ronnie22 schrieb:

Which mdf did you use? Would 25mm Nuwood mdf do? Somebody suggested 2 slabs of 25mm mdf for each of the side walls.

I did not use Nuwud MDF but some south east asian import one.
the front panel is made by a diffenrent company from the ones used for the other sides. 25mm is more than enough and for a bookshelf maybe a bit too much. 50 mm of MDF is way way to much and not at all recommended. it would block the air from being circulated towards the rear motor structure and magnet of the drivers causing them to heat up and undergo changess in impedance and drive them to failure at much less power levels.

Ronnie22 schrieb:

Too many questions actually in hindsight ;-)

Good that you ask them now and not later when u ask ur carpenter to start work on it or when u have already spent money on something u would not be able to use effetively.

Krish schrieb:

Obi-wan, I must say that I'm mightly impressed with all your effort. Are you planning to build custom amplification as well, to drive these speakers ? Great Stuff. And as sub_boss would say Krish

Thanks for that Krish. Don't want to get ahead of myself but it really is turnign out pretty nicely.
A lot of people have helped me in this project.
Once it is completed i will make a post acknowledging every one of them(if it gets done that is).
My carpenter is a Rajasthani and seems to understand my instructions as to how the cabinet shoudl be and guess that's helped me a lot.

Regarding amplification.
yes i will be using home brewn amplifiers to power these speakers.
they will be powerd by 6 channel amplifier made form chip amps.
around 170-180 watts in total for wach enclosure.
Cheers
Sachi

Hi Sachi,

I'm impressed by your efforts. You clearly are approaching speaker building with a lot of dedication. BTW is bracing only employed in floorstanders to impart rigidity or would it be useful in bookshelves as well?

When you say that you are building the amplifiers, do you mean power amplifiers or control amplifiers too?

Benks

Really great work. Cant wait to hear this.

Deepu

Dear Benks,

Way to go Benks.

I am sorry I havn't been of much help lately.

In case you are arounnd in Jan and you need any additional help...I would be happy to chip in !

Regards,

Junia.

hey sachu,
the pics are not visible even in my friend`s sys so please post the links so that everybody can see it.

best regards,
Sandeep

I saw the pics clearly benks....and see them clearly each time I come to the thread....

manek.

Sandeep i'lll send the pics to you later. U are the only one who seems to be having a problem with the pics.

Thanks to the all for the kind words.
Hopefully the enclosure should be completed tom.
Once it is done i'll post pics for your review.
Neutral, i will be using chip amps made from LM3886(Dual mono chanels) and the other four channels would be made using LM4780s used in the stereo mode.
Cheers,
Sachi

p.s: Junia, hope to speak to you soon.

Dear Benks,

I am online now. So whenever you have the time drop me a line and we shall talk over Skype.

Regards,

Junia.

deepug schrieb:

Really great work. Cant wait to hear this.

That makes two of us.

jsa_ind schrieb:

Dear Benks, Way to go Benks. I am sorry I havn't been of much help lately. In case you are arounnd in Jan and you need any additional help...I would be happy to chip in ! Regards, Junia.

It would have been awesome if we could have measured the t/s parameters before i went ahead with the cabinet.
But i guess , we can do it once you get here.
Thanks for burnign them in for me.

Benks 2) My only audiophile view had always been "listen to as many systems as possible...that enables you to make better decision". However, i have never said that a particular perspective of audiophile concept is better than other. Benks, you had and still have the oppurtunity to listen to many hi-end systems in Bangalore...that will enhance your ability to further perfect your projects..my earlier postings was to encourage you to listen as much as possible...and also to take feedback from other audiophiles who have heard many systems. This had helped me in the past...and still continues to help. 3) The reason for my recommendation on the approach for loudspeaker was not intended bcos i wanted you to buy a kit, but bcos, there were a few technical issues that are bit complex to handle in a first DIY project...including time alignment, baffle diffraction and phase-coherence. In my opinion, the first DIY project should be focused on learning the basics. Ofcourse, if you are using a proven design as the basis for your project or have done sufficient homework yourselves , you need not worry about these aspects. Cheers Siva. COMMERCIAL MEMBER

Baffle diffraction is still an isssue if i go passive and i know that their are a couple of very effective ways to reduce them to almost zero. But by going active, i will be circumventing this issue. I know that i am a novice in this and make no attempt to hide this fact. I hae learnt a lot but not as much as i had hoped. Once i get my hands on some measuring equipment maybe i will learn a lot more.

I do know that listening to good systmes will improve and help me in desiigng and implementing better systems but that has not been easy either for various reasons.
I must confess that i have not exhausted all my avenues to learn and experiment with the project that i have undertaken and is one thing i regret the most.
Cheers,
BEnkenobi

Dear Benks,

Anytime Benks....just to let you know after burning the Fs goes down by 10 to 15%...you might want to compensate for the same.

I plan to get some more DRA gear as MLSSA's office is just a hop skip and jump from my place in Sarasota.

I guess fine tuning things at your place, with MLSSA should really get your speakers & room going !

Regards,

Junia.

jsa_ind schrieb:

Dear Benks, Anytime Benks....just to let you know after burning the Fs goes down by 10 to 15%...you might want to compensate for the same. I plan to get some more DRA gear as MLSSA's office is just a hop skip and jump from my place in Sarasota. I guess fine tuning things at your place, with MLSSA should really get your speakers & room going ! Regards, Junia.

Ahhh! Can't wait for that to happen.

jsa_ind schrieb:

Dear Benks, I plan to get some more DRA gear as MLSSA's office is just a hop skip and jump from my place in Sarasota. I guess fine tuning things at your place, with MLSSA should really get your speakers & room going !

Hi Junia and Sachi,

What's 'DRA' and 'MLSSA"?

Guys two more hours of work left on the speakers.
Here's an update.

Almost finished!

http://img226.imageshack.us/img226/2200/image0128vh.jpg(only for Sandeep)


Woofer loading.

http://img188.imageshack.us/img188/7483/image0096kz.jpg(For Sandeep)


The back of the speaerk where the glass wool packing can be seen.

http://img31.imageshack.us/img31/6763/image0082ki.jpg(for sandeep)


Here the ports can be seen.
They are sealed off from the inside to just in case the glass wool tries to come out .
The cloth is speaker grill cloth generously provided by Mr.Arasu.images/smilies/insane.gif

http://img166.imageshack.us/img166/4210/image0106iu.jpg(for Sandeep)
Gosh! I need a break and a cold beer.
Cheers guys,
Sachi

Guys forgive me for the poor quality of the images.
I will post better ones later tonight or tomorrow morning.
Cheers,
Sachi

Here are better quality pics.

Front..

http://img355.imageshack.us/img355/7757/img00422ni.jpg(for sandeep)


Front and back

http://img358.imageshack.us/img358/4923/img00431ev.jpg(for sandeep)

Damping

http://img265.imageshack.us/img265/2075/img00370yx.jpg(for sandeep)


POrts

http://img195.imageshack.us/img195/928/img00384st.jpg(for sandeep)

Cheers,
Sachi

really a good work....they look great........i sort of envy u now......

They do look good don't they.:D

The grill frame is done. If you can see in the first picture , u will see that one of the grill fastener cups is missing.
That's because i screwed up by telling my carpenter to do something that i should not have asked him to.
so will have to get another one from Arasu and press fix it later on monday.

I will publish the bill of materials and cost of labour later, cause i think some of you would be curious how deep a dent this thing made in my wallet(not to mention my Dad's ).
This thing would not have been possible without his constant and unyielding support.
Regarding the total cost, be prepared to be surprised and blown away.;)
Cheers,
Sachi

hey sachu i can seee ur pics man... no porblem i can easily see them and no need of any links from now onwards....
There was some prob with my firewall... now i can see the pics
and they look very nice... man ... good job...

hey benks.....

they look awesome except ofr the exterior finish which wud make it look more great......have u taken the demo?......how is the performance?......do share ur experience with the speakers.......when can we get the opportunity to hear them?......

edges

benks....

sorry man i didnt see the enlarged pics.......u have put the laminates for the exterior right.....

edges

That's right..
those are PVC laminate stick ons .
i paid 750 bucks for a roll of 55 square feet.
that's actually a lot more than i would need but since construction is going on it leftovers would be used up.
This was the cheapest and most VFM solution i could find for the exterior finish.

Regarding auditioning the system
there are a 'couple'(did i say couple...) of things that need to be sorted out.
i need to have 6 channels of amplification and most importantly have to check if the active xover is working and see if there are any attenuations in the freq response and also the smoootheness of the curves.
the amplifiers are actually almost complete .
only parts missing are heatsinks, transformers(i need 3.4k for this ) and of course the case.

I am presently in a bit of a resource crunch and hence will not be firing up these babies for quite some time..
need everything to be in working order and satisforry conditions before i do it.

Will let you know as things progress.
Cheers,
Benkenobi

Benks,

Good Work! Keep it up!

The clink you hear is just me loading some beer bottles in a bag, on my way to your place to give your babies a workout....

Cheers

Dear Benks,

Good job !

Let us know about the costs Sachi. It would be nice to do a cost comparision with Ronnie and see what the figuers are apples to apples.

Regards,

Junia.

Dear sachu,
working with first project with electronics is not a easy task tat too u are using a crossover active one with linkwitz one with 4th order>?>>> hmmm man like i said on that day better first you go with a second order passive crossover so that you can save lots of money and in the near future you can upgrade it to the active one after lots of refinement.

with Arasuks inductor(each) costs something like 1500 bucks.... ( i think u said regarding this) But for this for his wattage I think there is no need to spend that much for the heavy guage. so better stick with the 18 guage so that your costs will cut down.

My strong recommendation is towards go with the passive first and then check the results and see are there any problems with the freq flatness and you can again change those settings in the active crossover.

best of luck

cheers,
Sandeep

I would opt for active speakers they sound much better & cleaner....anyone want to debate this is more than welcome.

Junia wrote :

I would opt for active speakers they sound much better & cleaner....anyone want to debate this is more than welcome.

I'm ready for a debate...but will take your side..hehehe..I told I'm wicked like Tuco...

Lets go for it Sub Boss now to find some worthy opponents !!

Any takers ??!!

Maybe we should start a seperate thread on this...what do you say ?

buurrpppppp,

Yeah Junia....a new thread will make discussions better as we would hijack benks thread...anyways benks you owe me beer dude, such a beautiful execution can never ever go without a party..

Dear Junia n Subboss, I do accept that active crossover system sound very good. I never argue regarding this. My opinion regarding sachu`s speakers is that he said that he spent at max and for completion he would take some more time. Thats why i said for temporary use I would like to recommend the passive one and after few weeks he can go for the active. Just to make the speakers sing at this moment thats it... i dont understand why will u be in the front of the line when you want to debate ok anyway I am also on your side so anybody who are intrested to argue regarding this just start up ..... probably this thread will become the hottest thread of HIfi-forum

Sonic Master wrote :

i dont understand why will u be in the front of the line when you want to debate

I think our choice for Active speakers proves that we don't want to be passive... in any discussion...May truth Prevail

Sonic_Master schrieb:

Dear sachu, working with first project with electronics is not a easy task tat too u are using a crossover active one with linkwitz one with 4th order>?>>> hmmm man like i said on that day better first you go with a second order passive crossover so that you can save lots of money and in the near future you can upgrade it to the active one after lots of refinement. with Arasuks inductor(each) costs something like 1500 bucks.... ( i think u said regarding this) But for this for his wattage I think there is no need to spend that much for the heavy guage. so better stick with the 18 guage so that your costs will cut down. My strong recommendation is towards go with the passive first and then check the results and see are there any problems with the freq flatness and you can again change those settings in the active crossover. best of luck cheers, Sandeep

Thanks for the suggestions sandeep.
but first indications after testing the crossover today were pretty good and am excited .

It was great meeting Abhi(abhi.pani) and we had a real good time auditioning speakers.
Thnaks dude..hope to get together with you, Mohan, et al soon..

the thing was that i could not check to see if there was distortion in the output cause i did not have acess to a scope and also the thing is the freq generator was one of fixed kind and not one where you can sweep the signal.
the other issue awas that the max freq that could be generated by it is 3.4k while my high freq xover point is 3.41kHz.
as you can imagine i got no output from both the midrange and the tweeter at this point. i felt this to be strange but i guess its better i get it checked with a scope and a freq generator that can be varied and that can go beyond 20k.

The otehr presets were at 300, 550,1000 and 1850.
i got signal only from the woofer output at 300 while at the rest of the points i got output only from the midrange.
the xover point is 350Hz.

However, there was an attenuation of the signal.
input was 500mV while output was 400mv.
this i think is because the output impedance of the freq generator was in the region of 700ohms.



Cheers,
Sachi

great job Benks..sounds really impressive !

BTW what is the sensitivity of your speaker ?

Hey arjun, am oing to lay off the project till i finish my GRe and that's going to be till after the 20th of October.

Anyway,
the sensitivity of the speakers are,
woofer-89dB(1W,1m)
midrange-88dB(1W,1m)
tweeter-91dB(at 2.83V at 1m).

I may only do work on the speakers when i feel bored and have time...

BTW, i have to come up with a design for a box to house the xover and the six channels of amplification!
will be getting it fabricated out of Aluminium by my friend.
only the plates of aluminium with the necessary holes and screw holes will be done by him.
the rest is just a little bit of bending and screwing them together.
trying to keep things as simple as possible.
Benkenobi

p.s:also, am in the process of experimenting the bass response of the wwoofer now that it is in the box.

so i presume u plan to tri amp ?

you must try the SI T Amp.
i just got it for €30 and have a regulated PSU for the same amount. Am awaiting my JMR twin IIIs to try them out ;)and the wait is too much

Hey benks, great going.. the speakers are looking "delicious"! Its a pity you need to stop on them temporarily now. How about testing them out first using a passive xover picked up from local market.. the xover quality may not be good, but it would be quick and who knows we might be surpised!

Hi! Ben,
good Job, keep the DIY fire burning.
Rgds

Prithvi

ravi schrieb:

Hey benks, great going.. the speakers are looking "delicious"! Its a pity you need to stop on them temporarily now. How about testing them out first using a passive xover picked up from local market.. the xover quality may not be good, but it would be quick and who knows we might be surpised!

thanks Ravi.
as much as i would love to fire them up, cost constrainsts are huge and the main objective for me is to check out the response of the woofer and see at what freq the box is actually tuned to and of cousre to get the xover thoroughly checked.

Cheers,
Benkenobi

Prithvi schrieb:

Hi! Ben, good Job, keep the DIY fire burning. Rgds Prithvi

Thanks for the kind words Prithvi,
Cheers,
Sachi

Arj schrieb:

so i presume u plan to tri amp ? you must try the SI T Amp. i just got it for €30 and have a regulated PSU for the same amount. Am awaiting my JMR twin IIIs to try them out ;)and the wait is too much

Hey Arjun,
give me an hour and i will post pics of the amplifier modules that i will be using.
Cheers,
Benkenobi

Okay guys,
here are the pics of the electronics.

The first picture shows the amplifier sections and their respective rectifier units.
The ones in the red boards are the dual mono LM3886 chipamps.

The one in the green board is a stereo chipamp based on the LM4780. Effectively it is a dual 3886 in a single die.
output is 60x2 RMS at 8 ohms. has inbuilt spike protection and also has a mute pin which can be configured to get a soft start.




A closeer view of the LM3886 chipamp.



A closer view of the LM4780 chipamp. Just take a look at the component count.
in fact many people on diyaudio.com tout these to be better than the rotels and the NAD in the sub 400-500$ systmes.
with better matched components and quality components these are true giant killers competeing with those that retail for 1200$ and above. Don't take my word for it, these are the views i have heard from the diyaudio.com members.




Only the amplifier sections..




Here is the active xover section along with the power supply which is incorporated on the board itself.
The transformer is torroidal made by Miracle(toroidal.com)



A closer look at the xover section.

The topmost part of the board from where wires are jutting out are the inputs and outputs.
The input is to the right while the outputs are , from the left towards right,
woofer,midrange and tweeter.

the opamps are TL074.

I will experiment with different capacitors once i have all things running.

as usual, fire away ..

Cheers,
Benkenobi

Hello sachu,
Better to keep your project works like this in the SOP (Statement of Purpose ) for the US universities. so man... they may be some plus points who knows... but best of luck man so when are u applying to US universities. Did u finish your your GRE exam? once again i will come to you and audition your system.

cheers,
Sandeep

Benks,

Make sure to test your amp on a cheap speaker....say a continius run of about 8 - 12 hours. In case something goes wrong with power amp... you might lose your expensive drivers.

I'ts better to be safe..

Cheer
Siva.

sivat schrieb:

Benks, Make sure to test your amp on a cheap speaker....say a continius run of about 8 - 12 hours. In case something goes wrong with power amp... you might lose your expensive drivers. I'ts better to be safe.. Cheer Siva.

Thanks for that Siva,
will use my old Murphy to test it out.
Cheers,
Benks

First Impressions




Okay guys, the speakers have been tested for an hour or so .
only the woofer was connected to the Nad and keeping the treble setting in the Nad to minimum and bass at flat the diamonds are obviuosly no match to my new babies.
They go deeper, tigher and louder .

but, i seem to have made a huge but simple(i hope that it is )blunder by directly screwing the drivers onto the front baffle made of 1 inch MDF .

And because of this the speaker makes a rattling sound when i turn the volume up to the 11 o clock position and the bass setting to maximum on the NAD.
have to sort this out ASAp before further testing.


Then i connected only the midrange keeping the tone controls flat.
The mids are smooth and sweet.
can't expect more for 150 bucks ,can you?

Can't wait to finish testing the xover sot that i can at least test one speaker to see how it performs
Cheers,
Sachi

Apologise in advance for my ignorance Sachi. But aren't drivers fitted to the baffle using screws? I don't get what you did wrong