TPA 3116 vs the tripaths

[beastwoo]

What is the 19V 6A PS you are using? I might not need it, as I already have the 24V 4A that came with it and that provides more than enough power beyond normal listening volumes. @Yatsushiro I did measure the voltage of the PS and it checked out. I don't know how to measure the amperage, how does one do that with a simple multimeter?

My 19V 6A power supply is a laptop-style brick, I think HP branded; I don't remember where I got it. I wonder if replacement power supplies for gaming laptops might be a good match, as the graphics cards for those laptops would have pretty big power requirements. I see Amazon has a few 19V 9A supplies, which may be overkill. I'd like to find something around 30V 6A, as suggested by @Yatsushiro. True, I would never use that much power, but I'm curious about whether the amp would sound different with extra power in reserve.

 

[Pio1980]

30 volts, afaik, is too much for most of these things. 19V/ 4 Amp + seems optimal for several, according to the thread.

 

[bubba42]

@beastwoo is talking about the TPA3250, not the TPA3116.

I am currently not thinking that I will need to worry about the ERROR light/shutdown, as it only happens at volumes I'll not use. But if I did, do we think that the FX502SPRO would need more voltage, more current, or both?

 

[Pio1980]

Maybe both. Instantaneous and sustained peaks vs PS source impedance could be the problem.

 

[45rpmspinner]

TI power ratings for TPA 3250 are based on 32 volts. Max is shown as 36 volts. Absolute Max at 38.5 volts.

TI wattage output charts are based on voltage increases since the amplifier will only draw whatever current it needs at any given time....based on the voltage.

If you're is shooting for max power with reasonably low THD, then 50 watts per channel at 8ohms [.1 THD] seems a pretty good target. At 60 watts it'll be 1% THD.
In that case, I'm thinking a 120 watt ps is minimum. So, maybe a 32V 5A or a 24V 6A ps? ....although I can't see that having more amps on tap would matter unless you start drawing enough current to kick off the protection circuits. Of course, before that happens you're probably going to be hearing a whole lot of distortion anyway.

Whether all boards can actually handle those values is another question.

 

[bubba42]

I am kicking off the TPA3250 protection circuits and the amp shuts off. Is that under-Voltage or under-Amperage? I don't want or need max power possible.

I did some more testing and think that the TPA3250 does sound significantly better than the TPA3116. It sounds fuller with more bass.

 

[45rpmspinner]

I am kicking off the TPA3250 protection circuits and the amp shuts off. Is that under-Voltage or under-Amperage?

24 volts is fine.
However, if the amplifier is trying to draw more current than is available, it can cause a voltage drop.
In short, it appears you didn't have enough Amps on tap.

 

[KingBubba]

I have been reading this thread from the wings. I have two TPA3116 units and nothing I have done is causing a shutdown. If this is an overheating issue, has anyone run with the case open and a table fan cooing the insides? If not an overheating issue, is it a possible impedance issue such as 4ohms or less on the load side? The third thing I am curious about is whether these amps are sophisticated enough that they can respond to a clipping event by shutting it down? I do not know enough about this technology to answer any of my own questions.

 

[bubba42]

The error/shutdown discussion is about the TPA3250, it has error circuitry built into the chip. Sorry if that is confusing. I try to label which amp I'm talking about

I don't think the TPA3116 has that. I have two of them as well, which were greatly improved by the gain mod.

 

[45rpmspinner]

I have been reading this thread from the wings. I have two TPA3116 units and nothing I have done is causing a shutdown. If this is an overheating issue, has anyone run with the case open and a table fan cooing the insides? If not an overheating issue, is it a possible impedance issue such as 4ohms or less on the load side? The third thing I am curious about is whether these amps are sophisticated enough that they can respond to a clipping event by shutting it down? I do not know enough about this technology to answer any of my own questions.

The TPA 3116/8 family has a number of built-in sophisticated protection switches.
The major ones appear to be dependent on current draw.
Some of which, when tripped, will mean you'll have to replace the chip.
The amps will clip, apparently in a "soft" manner, but I personally haven't experienced it.

 

[Pio1980]

TI power ratings for TPA 3250 are based on 32 volts. Max is shown as 36 volts. Absolute Max at 38.5 volts.

TI wattage output charts are based on voltage increases since the amplifier will only draw whatever current it needs at any given time....based on the voltage.

If you're is shooting for max power with reasonably low THD, then 50 watts per channel at 8ohms [.1 THD] seems a pretty good target. At 60 watts it'll be 1% THD.
In that case, I'm thinking a 120 watt ps is minimum. So, maybe a 32V 5A or a 24V 6A ps? ....although I can't see that having more amps on tap would matter unless you start drawing enough current to kick off the protection circuits. Of course, before that happens you're probably going to be hearing a whole lot of distortion anyway.

Whether all boards can actually handle those values is another question.

Voltage is the one to mind on the upper end limit, the chip and usage determines current draw. It will draw the current it needs at voltage, up to the available limit of the power supply.

 

[Poultrygeist]

I am kicking off the TPA3250 protection circuits and the amp shuts off. Is that under-Voltage or under-Amperage? I don't want or need max power possible.

I did some more testing and think that the TPA3250 does sound significantly better than the TPA3116. It sounds fuller with more bass.

How efficient are your speakers?

 

[bubba42]

The TPA3250 sounds better with two speaker sets that I tried, 98db Klipsch and 86db KEFs. Better in the same way, fuller and more bass. That said, efficiency should just be about loudness to the listener. They are both 8-ohm speakers, which should be more of what the amp feels.

 

[Pio1980]

The TPA 3116/8 family has a number of built-in sophisticated protection switches.
The major ones appear to be dependent on current draw.
Some of which, when tripped, will mean you'll have to replace the chip.
The amps will clip, apparently in a "soft" manner, but I personally haven't experienced it.

I thought I'd heard a "brittle edge" to mine at fairly high levels, but need further listening to positively confirm.

 

[45rpmspinner]

If you're is shooting for max power with reasonably low THD, then 50 watts per channel at 8ohms [.1 THD] seems a pretty good target. At 60 watts it'll be 1% THD.
In that case, I'm thinking a 120 watt ps is minimum. So, maybe a 32V 5A or a 24V 6A ps?

Not that it really matters, but I need to amend the above statement in a rather obvious way. Electricity 101, as it were.

These amps are highly dependent on voltage for power. Thus at 24V, the most wattage you can expect to get out of TPA 3250 is around 40 watts per channel at 8 ohms with relatively little distortion .....simply because the amplifier will only draw so much current at that voltage.

 

[45rpmspinner]

I've been looking at the specs on TPA 3250.
It's protection triggers are specifically heat dependent......which, based on what I've seen, appears to be different than than TPA 3116.
This also includes "under voltage" protection. So, even that "fault" is actually heat related.

Pushing the amplifier until it clips, as well as heavy amplitude transients at too high volume, can cause a "fault".
However, I think that may be based on how frequently those conditions occur. A "soft" protection trigger???

Too low speaker impedance dips? Unbalanced speaker loads? A slight short at the speaker terminals?
Yep, there's protection for those situations too.

Actually, a remarkably comprehensive system.
If anything, I think it's perhaps less forgiving than what some of us are used to.

 

[bubba42]

More testing, I figured out a better testing setup. I hooked up the FX502SPRO to one speaker and the single-chip Breeze to the other of my best speakers. I then hooked up a chromecast to each as input and casted the same songs to both. Then I could quickly flip between the two. The FC502SPRO TPA3250 was noticeably better, fuller and more bass. My wife, who was blind testing also agreed. I switched which speaker they were connected to and she still thought so.

So I think that the three of us that have tested it (on this forum and DIY audio) agree. I'd love to hear from more. It is a worthwhile upgrade and is quite inexpensive.

 

[hifix]

Hi Bubba42,

I'm not too sure how it works with the newer board but unless the older board is configured to mono you might want to have a suitable load connected to the unused speaker output before you crank the volume up. To the best of my understanding, if the output filter starts of oscillate and the oscillation is bad enough, the filter capactor takes a hit.

 

[bubba42]

Ah, well we were only listening at low to moderate volumes.

Sheesh, it is already very hard to test these things. That method allowed me to go switch quickly so I could make much better comparisons. There is already so much subjectivity and bias.

 

[Poultrygeist]

Comparing the two and with all the upgraded parts standard on the Volt+ I don't believe the stock TPA3250 would offer any sonic advantage with efficient speakers.

It would make sense to consider a 3250 if you need the extra power. Even so that comes at a higher price as the 3250 requires a more expensive power supply.

I don't plan to buy a TPA3250 but my name is on the list for the new Volt+ power amp.