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Old 7th August 2013, 08:22 AM   #71
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First and foremost, thanks for such a meticulous analysis of the sure TDA7498 board. I got myself one and modified it according to your recommendations.

Now, my question is: I intend to design a custom board based on the TDA7498, and the load to drive is 4 ohm. I see you've tested 4 ohm with good results, but the datasheet only mentions 6 and 8 ohm loads. Is it safe to use 4 ohm long term or is there any associated quirk? (I'm thinking of, for example, short circuit protection).

Thanks.
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Old 7th August 2013, 05:38 PM   #72
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Quote:
Originally Posted by iggarpe View Post
Is it safe to use 4 ohm long term.
No. Hence the datasheet specifically only shows 6 and 8 ohms performance.

You can parallel the inputs and outputs however, and then it'll run 4 ohms. It'll be only 1 channel naturally though.
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Old 7th August 2013, 08:02 PM   #73
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Quote:
Originally Posted by Saturnus View Post
No. Hence the datasheet specifically only shows 6 and 8 ohms performance.
Oops. The TDA7498E version is specified for 4 ohm, but it costs almost twice as much (no big deal for my app) and is much more diffcult to supply (big deal for my app).

Care to suggest a similar simple class D IC amp that can output 60+60W on 4 ohm loads?. (single positive supply rail)

Quote:
You can parallel the inputs and outputs however, and then it'll run 4 ohms. It'll be only 1 channel naturally though.
And how would you parallel the outputs?. I mean before or after the LC filter?.
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Old 8th August 2013, 11:13 AM   #74
SNY is offline SNY  Hungary
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Default IRS2092

IRS2092 + IRFB4019 + T130-2 distortion tests without AES filter. (ESI Juli@)

Rail: +/- 50V DC
Load: 8 Ohm resistive

http://audiodiyers.hu
Attached Images
File Type: jpg 507.jpg (49.0 KB, 439 views)
File Type: png freq_response.png (22.8 KB, 435 views)
File Type: png IMD_0_057_100w_8R.png (33.7 KB, 432 views)
File Type: png THD_0_015_100w_8R.png (33.6 KB, 425 views)
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Old 21st January 2014, 10:00 PM   #75
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Well, STA505 has the worse THD but it has the better sound for me, much better than STA510A / STA517 and TDA7498.

Xonar DX has lower distortion and higher SNR but I prefer a thousand a times more the Auzentech Forte sound....
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Old 28th June 2014, 10:19 PM   #76
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Quote:
Originally Posted by iggarpe View Post
And how would you parallel the outputs?
I'm searching for this, too.
Maybe someone achieved that in the meantime?

I would like to use this board from ebay (16 incl shipping) for a budget subwoofer project with an 4 ohmer.
Click the image to open in full size.

edit:
TDA7498 (forgot to mention)
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