I'm going to give these budget 10mH Ebay chokes a listen to tomorrow.
Has anyone else changed the chokes on this board yet?
Looks like the fun provided by these 17$ toys never ends
I understand that RF interference could be very annoying. I heard someone lives around Toronto (fairly close to the CN tower) said that almost any piece of metal picks up RF due to the transmission from the tower. However, the area where I am in, RF was never a problem - I used twisted unshielded interconnects (1.5 M long) for the longest time and never have problem.
Looking forward to hear your comments.
Regards,
Looks like the fun provided by these 17$ toys never ends
I understand that RF interference could be very annoying. I heard someone lives around Toronto (fairly close to the CN tower) said that almost any piece of metal picks up RF due to the transmission from the tower. However, the area where I am in, RF was never a problem - I used twisted unshielded interconnects (1.5 M long) for the longest time and never have problem.
Looking forward to hear your comments.
Regards,
I guess I'm also lucky in that regard. Where I live, "over the air" radio and TV signals are weak at best (we call it the land of no reception). Almost all of my hi-fi cabling is unshielded.
I never had any luck with FM reception with the Lepai 2020 or the more expensive SMSL, the signal became jammed. All the other TDA TPA boards I've purchased did not suffer this way.I'm going to give these budget 10mH Ebay chokes a listen to tomorrow.
Has anyone else changed the chokes on this board yet?
Looks like the fun provided by these 17$ toys never ends
I understand that RF interference could be very annoying. I heard someone lives around Toronto (fairly close to the CN tower) said that almost any piece of metal picks up RF due to the transmission from the tower. However, the area where I am in, RF was never a problem - I used twisted unshielded interconnects (1.5 M long) for the longest time and never have problem.
Looking forward to hear your comments.
Regards,
I live in Baldwin,Ont and am listening to 91.7MHz (CIXL, St. Catherine's), with 28dBuV. Of course I have a deep fringe Yagi&, it is stuck pointing about 45degrees E of where is should be at line of sight for this station.
You really need shielded inductors and ferrites as shown in the spec & app notes, to get good EMI rejection. Some of the pcb's I see have cheaped out, using un-shielded L's.
BTW, "AM"reception, is a big issue with Class "D", need to shield the heck and use shielded cable to a remote antenna or forget it.
You really need shielded inductors and ferrites as shown in the spec & app notes, to get good EMI rejection. Some of the pcb's I see have cheaped out, using un-shielded L's.
BTW, "AM"reception, is a big issue with Class "D", need to shield the heck and use shielded cable to a remote antenna or forget it.
I think the TPA3116D2 (and/or is the the 3118?) has selectable oscillator frequencies via dip switch settings to 3 of the pins and you can go from 400kHz to 1.2MHz. Let's you set the RF to a region less 'bothersome' if needed. A nice feature which probably many of us will never bother to mess with.
Yup, AM suppression ckts, great idea. I spun my pcb before 3116 was out, so was stuck with 3110. TI figured it out as I was discovering the issue as well with my AM radio ckt.
It is unbelievable the diff between AM and FM.
Need to design/build another pcb, using 3116, to try out this feature. Maybe it is only saver for the AM.
Easy to do in FW, tune to station, get S/N info, store+, count+, chg 3116 op freq, loop, determine best S/N, chg to stored. Nice feature for the radio, if it works.
With the AM band, there is noise everywhere and no means of suppression. The ckt's can't remove, not even a DSP can sort the noise from the signal.
Now that I think of it, you really need a remote AM/SW antenna, with built-in LNA, using a BF862, to incr. S/N. Ambient noise is still an issue with AM.
Enjoy these parts they really are good. I have an old Pioneer SX-950 and never use it anymore unless I want to really blast the tunes.
It is unbelievable the diff between AM and FM.
Need to design/build another pcb, using 3116, to try out this feature. Maybe it is only saver for the AM.
Easy to do in FW, tune to station, get S/N info, store+, count+, chg 3116 op freq, loop, determine best S/N, chg to stored. Nice feature for the radio, if it works.
With the AM band, there is noise everywhere and no means of suppression. The ckt's can't remove, not even a DSP can sort the noise from the signal.
Now that I think of it, you really need a remote AM/SW antenna, with built-in LNA, using a BF862, to incr. S/N. Ambient noise is still an issue with AM.
Enjoy these parts they really are good. I have an old Pioneer SX-950 and never use it anymore unless I want to really blast the tunes.
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Agreed, AM is not Hifi. So the ? I have is,
Would you use/buy/build my portable stereo/radio/mp3/USB Audio Codec, knowing that it had no AM?
Getting the AM to work, is an engineering challenge for me, so that is as good as or better than a regular portable radio, as you say.
Funny how some people think Class "D" is not Hi-fi either
I was quite frankly skeptical, since all I knew was big power Class "AB", until I listened. Forget the spec's, listen.
It just fortifies that the source & speakers are always the weakest links in the path to your ears/brain.
Would you use/buy/build my portable stereo/radio/mp3/USB Audio Codec, knowing that it had no AM?
Getting the AM to work, is an engineering challenge for me, so that is as good as or better than a regular portable radio, as you say.
Funny how some people think Class "D" is not Hi-fi either
I was quite frankly skeptical, since all I knew was big power Class "AB", until I listened. Forget the spec's, listen.It just fortifies that the source & speakers are always the weakest links in the path to your ears/brain.
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Funny how you mention CBC, as I am listening to RAD2 (94.1M,Toronto), a strong, over the air signal(47dBuV, full stereo).
Others have said on this forum, that Internet radio was better than over the air. So I did the test, air is way better SQ, as far as I can tell.
It is like the diff between low bit rate MP3 vs a .wav file. Something like AM to FM. Not one dropped packet over the air
The specialty channels work, but I have BW limits on my internet, so it ain't such a good idea for me, as it may end up costing me more $ and I have at least 30 FM stations to pick from.
Yes, this is a TPA3116 thread, as all my testing was done using TI class "D" technology!!
Others have said on this forum, that Internet radio was better than over the air. So I did the test, air is way better SQ, as far as I can tell.
It is like the diff between low bit rate MP3 vs a .wav file. Something like AM to FM. Not one dropped packet over the air
The specialty channels work, but I have BW limits on my internet, so it ain't such a good idea for me, as it may end up costing me more $ and I have at least 30 FM stations to pick from.
Yes, this is a TPA3116 thread, as all my testing was done using TI class "D" technology!!
My CBC listening is with a tuner with just a piece of wire hung over a picture frame! My internet radio listening is restricted to nothing under 128Kbs.
I'm really enjoying my 3116 but not sure I should have ordered the 2.1 after playing with an old Kenwood powered sub I forgotten I had.
I connected a CD player directly to the sub and and added some volume.
It sounded 'orrible, 'orrible, 'orrible, just like those little punks that drive around with their Civic windows opened.
There was no overtones, it just sounded like someone wacking a wardrobe with a Tinpani mallet. I sure I would get a headache after 10 minutes.
Perhaps subs sound bad on their own?
I'm really enjoying my 3116 but not sure I should have ordered the 2.1 after playing with an old Kenwood powered sub I forgotten I had.
I connected a CD player directly to the sub and and added some volume.
It sounded 'orrible, 'orrible, 'orrible, just like those little punks that drive around with their Civic windows opened.
There was no overtones, it just sounded like someone wacking a wardrobe with a Tinpani mallet. I sure I would get a headache after 10 minutes.
Perhaps subs sound bad on their own?
I do not use a sub. If you want to make things shake, then you need lots of watts, you are trying to move the ground, rather than air.
Use the TPA3116 in a push-pull/bridge(BTL), as done in the DS, figure 27. Shows driving 2 ohm. How many Class "AB" PA's do you know that will drive a 2 ohm sub and will not blow up?
I think Class "D" is perfect for subs, since most of the energy is in the low end, this is where the eff gains really matters and distortion is not as important. Most woofers are not sub 1% THD as it is.
Use the TPA3116 in a push-pull/bridge(BTL), as done in the DS, figure 27. Shows driving 2 ohm. How many Class "AB" PA's do you know that will drive a 2 ohm sub and will not blow up?
I think Class "D" is perfect for subs, since most of the energy is in the low end, this is where the eff gains really matters and distortion is not as important. Most woofers are not sub 1% THD as it is.
Only sub (bass) no highs? why? Of course it sounds like crap, try connecting the phases diff. on the L & R, same/similar effect.
I'm sorry to hog this thread, but - any comments on this? Should I go for a "renowned" MeanWell PSU, or could buy a generic one for 2/3 of the price? Should I opt for a full 200W, or will 150W be more than sufficient?
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You need to take the speaker test, you will be suprised. http://www.diyaudio.com/forums/mult...much-voltage-power-do-your-speakers-need.html
The thread is long, but take the test and go to page 11 for the math explanation, many got confused.
My old 15ohm speakers only require .085 watts for my serious listening level. I also tested a pair of 4ohm 3 way sealed enclosures and they required 2.88 watts.
There's lots of music that can benefit from a subwoofer. It's not that clear cut. Having the sub properly integrated with the system would help I imagine. I don't think it' a waste.
Kyle
Before buying that specialty power supply, connect any old laptop 19 volt brick you have lying around. We all have at least 3 of them from old pc's. It may plug right into the jack on that board. Listen to it and I think you will see that it provides you all the watts you will need for 95% of the time. The 3116 is a 50 watt nominal rated chip with 10% distortion at 50 watts so you really don't want to operate there anyway. If you stay below 40 watts I think the distortion figure is about 0.1%. The basic equation for volts as a function of power and impedance is P=V^2/R, solve for V=sqrt(P R). For 40 watts and 8 ohms, V=sqrt(40 x 8)=sqrt(320)=17.9volts. Thus a 19 volt 90 watt power supply is perfect for driving this amp at up to 40 watts, which you really don't want to go above anyway.
So, the power supply you need, you probably have already, if not order a no-name brand one or a HP (with grounded plug) for $8 on Amazon or the like.
I am still waiting for the amp to arrive. However, if this amp check out, I am thinking of buying 3 more so that I can use them in balance (bridged?) configuration. This can readily be achieved using those tiny single ended to balanced converting boards (5-6 US$ each) found in EBay. My 84 dB speakers need some good clean power to play loud.
Regards,
Regards,