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Old 22nd July 2013, 06:34 AM   #101
sangram is offline sangram  India
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csom: All drivers need enclosures and crossovers optimised for their specific operating parameters. Though it is possible for a driver to work in a couple of variations in enclosure size and a minor variation may be tolerable, crossovers always have to take into account the exact driver behaviour at the point of crossover.

There are no plug and play designs, no matter who says otherwise. Only if your drivers are of very poor quality will they work equally in all designs, because their performance is so bad that the rest of the product does not make it any worse.

One thing to note about the change in level on your front panel: Note that one, and only one of the level settings is correct. There is no second position of the level controls that offers correct crossover behaviour. I feel you are using them as tone controls, which is not the right way to operate an active crossover, and it is not intended to be used as such.

To understand a bit about how complex it is to design a crossover, and also why an active crossover is not as easy as it is made out to be, read this project by Tarun (tcpip on this forum): The Asawari | dhandanought.org/tcpip

As to on-wall designs, it is not recommended to place a normal dynamic driver in a box on the wall as it severely compromises its radiation pattern and the resulting performance.

If you have a space issue, subwoofers with smaller 'satellite' speakers are the way to go. As Tom says and I have earlier said, post your speaker queries on the speaker forum. You will get far more expert opinions and advice there, because the speaker regulars tend to check that out more often than this one.

Good luck with your project.
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Old 22nd July 2013, 01:38 PM   #102
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Originally Posted by gootee View Post
Som,

...........

You will need to look here, and start a thread if necessary:

Multi-Way - diyAudio

Cheers,

Tom
Thank you so much Tom.
I will create a thread there.
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Old 22nd July 2013, 01:48 PM   #103
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Quote:
Originally Posted by sangram View Post
csom: ...............
There are no plug and play designs, no matter who says otherwise. Only if your drivers are of very poor quality will they work equally in all designs, ........................................
My drivers are not "very bad" sound wise. The only problem is I have no specific data available on them.

Quote:
Originally Posted by sangram View Post
One thing to note about the change in level on your front panel: Note that one, and only one of the level settings is correct. There is no second position of the level controls that offers correct crossover behaviour. I feel you are using them as tone controls, which is not the right way to operate an active crossover, and it is not intended to be used as such.
True, but since I have no measurement instruments or adequate knowledge of adjustment according to the room acoustics with non standard drivers, this is convenient for me at this moment.


Quote:
Originally Posted by sangram View Post
To understand a bit about how complex it is to design a crossover, and also why an active crossover is not as easy as it is made out to be, read this project by Tarun (tcpip on this forum): The Asawari | dhandanought.org/tcpip
.
Thank you very much. I will read.

Quote:
Originally Posted by sangram View Post
.....................As Tom says and I have earlier said, post your speaker queries on the speaker forum.
Good luck with your project.
Thank you sir. I will do. Please keep an eye there too.
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Old 2nd August 2013, 03:52 PM   #104
masood is offline masood  India
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dear all readers,
can any one donate me the lm3886 ic thanking you.?because in my small city there is not available this type of ic thanks
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Old 2nd August 2013, 07:33 PM   #105
gootee is offline gootee  United States
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Quote:
Originally Posted by csom View Post
My drivers are not "very bad" sound wise. The only problem is I have no specific data available on them.



True, but since I have no measurement instruments or adequate knowledge of adjustment according to the room acoustics with non standard drivers, this is convenient for me at this moment.



Thank you very much. I will read.



Thank you sir. I will do. Please keep an eye there too.
If you have a sound card in your computer, and if you could borrow a measurement microphone, then you could measure a lot of their characteristics, using free software like ARTA; enough to properly design enclosures and crossovers, I think.
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Old 2nd August 2013, 08:10 PM   #106
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If you have a sound card in your computer, and if you could borrow a measurement microphone, then you could measure a lot of their characteristics, using free software like ARTA; enough to properly design enclosures and crossovers, I think.
Thank you so much gootee!
I have a sound card and made a custom microphone as a measurement is not accessible to me at this moment.

I have already started a thread in the multi-way forum and fiddling with Arta and Room Eq Wizard and posted some snaps there.
People are very kind and helpful there too like all of you here.
Kindly have a look at there and post your valuable suggestion.
Here is the link:
Need Help with The Smallest 3 way Speaker Plan for LM3886 Triamping
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Old 2nd August 2013, 08:50 PM   #107
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dear all readers,
can any one donate me the lm3886 ic thanking you.?because in my small city there is not available this type of ic thanks
Dear Masood,
I can understand your frustration very well.
I had to wait for almost a year to get the chips in my area as I told you earlier.

Meanwhile, why not try a bi-amping or tri-amping with TDA2030 or TDA2050?
You can hardly differentiate between the sound of active bi-amping or tri-amping mode and that of a pair of LM3886 using a passive X-over.

TDA2030 pretty good sounding ( Rs. 15 per piece ) for average Indian music due its kinda compressed sound.

I did the same thing earlier while awaiting the availability of LM3886, and I am still in love with my TDA2050 tri-amped system.

In India, where we have no good drivers and associated good matching crossover available easily, active amplifier is the only solution to obtain pristine sound quality.

Even with LM3886, you might not be able to achieve your "dream sound" if you have crappy speakers and poor quality compressed audio source.

But tri-amping can save you in this situation to a great extent.

You can trust me. I am giving an honest suggestion from my DIY experience.
I opend a TDA2050 thread here long ago and got help from many kind members.

And for Active X-over, there are plenty of tested circuits both in our forum and on the internet. Sir Mile, APEXAUDIO, has posted some. Rod Elliot has some good quality Active X-over circuits too. ( In fact I made my first two way active X-over following his site and was amazed at the unprecedented impressive sound. )

At present I have 3 systems.

1) One with tri-amped TDA2050, ( with 6 TDA chips, Rs. 30 to 45 per piece)
2) another with tri-amped LM3886 ( with 6 LM3886 chips )
3) and the last one is just a normal stereo with a passive two way system ( With 2 LM3886 chips, I just made this to compare the sound with my active Tri-amped system)

I tested 3 systems simultaneously using the same input source, using a 5 band equalizer for spectrum enhancement.

The sound of system 1 and system 2 is really great and one can't really tell the difference at low volume and they are a clear winner over system 3 or way better than system 3 which has also been made using 2 LM3886 chips.

If you find no LM3886 for the time being, you can easily get 6 TDA2050 chips at the cost of an LM3886 easily.

Or if anyone can donate you some LM3886 chips, that will be a different story.

Anyway, just added my two cents to heal your utterly frustrated desperation.

Good luck. Hope someone will donate you if they can.
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Last edited by csom; 2nd August 2013 at 09:17 PM.
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Old 3rd August 2013, 04:38 AM   #108
masood is offline masood  India
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dear csom,
thank for your advice,i have two pair of mosfet 2sk1058 and 2sj 162 how will the sound of these mosfet do u have any experience .thank u sir
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Old 3rd August 2013, 11:10 AM   #109
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dear csom,
thank for your advice,i have two pair of mosfet 2sk1058 and 2sj 162 how will the sound of these mosfet do u have any experience .thank u sir
Dear Masood,
A good sound depends on several factors, as I learnt from reading innumerable posts by the audio gurus here and from my personal DIY experience and I am still learning each day here at Diyaudio forum with the kind help of all.

1. Quality of components.
2. PCB layout design
3. Adequate filtration of the power source
4. Proper grounding ( very important )
5. The quality of audio source and preamp
6. Quality of speakers and cross over
7. Your listening environment etc.

Any compromise is bound to affect the proper reproduction of the desired sound.

I assembled/ built/tested at least 6 discrete amplifiers. You know good quality components are beyond the scope of average Indian hobbyists. And more, the cheap commercial "high end" discrete MOSFET Amp kits available locally, use low quality components, badly designed PCB and inadequate filter capacitors. Result ? Hum, unwanted noise. They let you feel that they are switched on. But they are loud ( with distortion figure too ). I felt the same with classic 2N3055 kits too.

Let me share with you a fact. Last year I purchased a so called "high end 1600 watt MOSFET kit" with much optimism. When everything done, I felt a low hum. I informed the vendor and he simply said "oh this is normal with such a high power kit". What the ....! I spent my money to buy a High End Humming Amp!!!!!!??? I was utterly frustrated. I tried increasing the filter caps and somehow I was able to tame down the hum to a certain tolerable level. But there was a wonky crossover distortion. And in Indian local situation, there is a "no return" policy once the "...." is sold.

Meanwhile, I was reading about TDA2030 chip on the net. I studied the data sheet and found a PCB design there. It was so simple. I used a marker pen and drew the PCB layout following the datasheet and etched it. And when I casually finished the amp, .....oh my god! The sound quality was far superior than my purchased "High end commercial ...." kit. I felt that my speakers were in need of that chip as their perfect companion.
Then I went one step ahead. And made a two way active amplifier following Sir Rod Elliot's two way cross over. Result? Unprecedentedly astonishing sound quality. My cousin brother who works in a studio with high end devices, was simply addicted to the detailed and rich sound and listened for three hours at a stretch until dad reminded us that it was almost dawn and "we must take some rest"! And the sound was coming out of an amp that cost me less than 4 packs of cigarette! And there was no crossover distortion!

I just had to discard my "high end discrete .... " and "upgrade" to TDA2050 as I needed a little more power. And that experience made me a lifelong fan of Chip amps for good.

My point of sharing this personal experience with you is that listening environment is also important. Do you really need monstrous power at home? Why not learn to polish your PCB making skill, designing PCB layout of both the amp and cross over, and develop a small low cost board with TDA2030 ( which should cost you less than a pack of cigarette ) meanwhile? Even a set of TDA2030 in stereo tri-amping mode can give you a pretty loud yet very rich sound!

LM3886 will surely be available in your locality very soon, if not today, tomorrow for sure.

My humble suggestion is if you can afford, go for an active amplifier system like I made and it will definitely and clearly outperform any of the locally available commercial craps. You will be pleasantly surprised, I can bet.

I followed Sir Rod Elliot's advice about using active X-over system, given on his website and I now feel how right he is!
For proper ground connection, kindly follow Sir AndrewT's posts, for a dead quiet system.

Hope this helps.
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Last edited by csom; 3rd August 2013 at 11:20 AM.
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Old 3rd August 2013, 12:58 PM   #110
masood is offline masood  India
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DEAR SIR,
thanks for sugestion i have both 2030 ic and its pcb.i will show you the pcb and its amplifier soon thanks again yours masood
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