Fasten seat belts. TDA8932 pessimistic review.

Edit: Note to NXP: You've still got the finest Class D amplifiers ever made so please don't discontinue them; because, indeed the fault is in the datasheet, not the chip. There seems to be a datasheet omission of the 470R series to inputs for bridged audio amplifier. There's no other fault. Previous communication follows, for historical documentation purposes (the responses would't make sense if I wiped the original post) It would be good to pay attention on how the initially pessimistic event turned into an exuberant promotion. Meanwhile, paying attention... (end of edit)

Long term test completed, and there's news. . .

I got one of these on a lark:
Digital Amplifier Board Module 35W Mono Power Amplifier Module Low Power TDA8932 | eBay
And, I really love that thing.

Sound Type: Ultra-Linear. Overcomp concert amp sound, quite similar to classic silver face receiver.

Datasheet: I've proofed the datasheet claims, and they're true (that's rare); therefore, the ideal usage is long duration music listening (especially apt for weak sources like smart phone), with an 8 ohm speaker, good ventilation for the amp and clean power too (linear reg or old school "runs warm" smps).
Exception: Advertised as a 35W amplifier. Actually, this is a 30W amplifier. This particular board, very nice otherwise, is a little small for 35 watt amplifier's dissipation needs. The difference cannot be audible. That was a nitpick.
Exception2: There may be dull results if [mis]used with either 4 ohm (heavy) load or non-linear (cheapest new laptop pack) power source. Actually, the datasheet has vague hints about that, but there's no outright mention.

What this amp does best is: Amplify Music, very much, as inoffensively as possible. This is fantastic with relevant phone sources (try the onkyo app's eq, because fun). It sounds similar to a classic silver face receiver and/or a real concert amp. It can be used for a speaker-building reference amplifier if using 8 ohm or lighter load speakers. Longer duration listening of music without listening fatigue, without trouble.

If there was a Class D amp made for people who don't like Class D amplifiers, well this is the one. I can't tell it is a gimmick. It sounds exactly like a 70's amp and it does not harm the ears any more than a 30W 70's amp could. That's a lotta praise.

What it can do poorly is: Not "shouty" enough to artificially highlight the voice tracks for tv/movies, not efficient enough to use in a sealed container, not gimmicky enough to use for autopsy-like dissection of music, and not quite stout enough to deliver hi-fi with 4 ohm and other heavy load speakers.

Low listening fatigue music-purpose amplifiers can be checked out with Star Trek Voyager's soundtrack, and listen for the little "tinkly" notes, and the dynamics surge. I thought it was passable on the treble effects of that soundtrack and excellent on the dynamics.
There's a lot you shouldn't use it for; however, this regularly misunderstood gem is worthy of a little respect if you had wanted some low-fatigue music replay.

I'm using it right now. It may be a little bit addictive? Yes, I can make a better amp at both more expense and bulk. However, there's not much better to be had if you'd wanted to use an 8 ohm speaker (or somewhat lighter load) for the purpose of long duration music replay in a small venue, such as a house.


EDIT: production variance
Basically, on the left is a hi-fi; or, on the right is a mid-fi. Caps and chips are some of the differences.
In the early part of the thread, I reviewed the poorer sample; and later, got a nice surprise in the mail.
539375d1458752865-fasten-seat-belts-tda8932-pessimistic-review-tda8950s.jpg
 

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Exception2: There are bad results if used with either 4 ohm (heavy) load or non-linear power source....
I'm using it right now. It may be a little bit addictive. Yes, I can make a better amp at both more expense and bulk. However, there's not much better to be had if you'd wanted to use an 8 ohm speaker (or somewhat lighter load) for the purpose of music replay in a small venue, such as a house.
Sorry, not quite sure I understand all what you said in this review :confused:
- How do you use it - obviously just as MONO, so you are planning to do two in STEREO, or?
- Also, it is supposed to be used with 8 ohm speaker(s), what did you mean in that last sentence?
So you suggest Linear PSU with it?
 
Sorry, not quite sure I understand all what you said in this review :confused:
- How do you use it - obviously just as MONO, so you are planning to do two in STEREO, or?
- Also, it is supposed to be used with 8 ohm speaker(s), what did you mean in that last sentence?
So you suggest Linear PSU with it?
Ideal usage involves:
- music replay purpose
- You'll probably want an attenuator, such as a potentiometer for volume control.
- an 8 ohm speaker
- linear regulator chip or older-style warm running SMPS (not the lowest cost new laptop pack).
- likely voltage range is 18vdc to 22vdc (that's the ballpark)
- monobloc or dual-mono, or for "stereo" use, the left amp's power circuit will pollute the right amp (and vice-versa) unless there's separation. So, if SMPS, use 2 diodes, left and right (series with V+). Or, if linear supply, use 2 regulator chips, left and right.

And how I use it is, for one big speaker for the office.
The output of this little amp is most suited for situations where lowest listening fatigue is most important, such as long-duration listening.

What not to do:
1. 6 ohm speakers, 4 ohm speakers, (overload causes dullness)
2. Cheapest New laptop smps from china (buying bad power)
3. Two amplifier boards on one power cable (causing bad power)
4. Television/movie sound (can do it but isn't optimal for that use)
5. The amp overheated in a sealed enclosure (board is very small)
 
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I used it (the chip I mean, not the same board as Daniel's) but found the high frequency too ragged for full range amplification. It did work fine in an active setup with its highest frequency (being fed from a passive line-level XO) being around 3.5kHz.
 
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