[lo_tse]

"MONO MODE (PBTL)
The TPA31xxD2 family can be connected in MONO mode enabling up
to 100W output power. This is done by:

• Connect INPL and INNL directly to Ground (without capacitors) this
sets the device in Mono mode during power up."


I have seen this stated in the Texas Instrument's info sheet for the TPA31xxD2
chip family as well. Since I have very little electronics knowledge ...could someone
please clarify 'which' ground it is that the left channel + & - inputs are connected to?
Where is the ground that you would physically connect to? Thanks.

Personally, I do not find it easy to convert the board from BTL to PBTL (stereo to mono).  Unless you have a PCB that is an exact copy of the TI evaluation board.  Unfortunately, every manufacturer of the available 3116 boards designs their board a bit differently to suit their need.  To figure out which point on the PCB is which point on the schematic, one has to examine the PCB and follow the traces carefully, using the components as a guide.  It is not technically difficult, just tedious.  The main reason that I bought the "Audiobah" boards is because they have marked the the spots on their PCB that needed to be linked when converting the board to mono. 

Regards,



 

[lo_tse]

Has anyone looked at the audiobah boards and figured out how to run them in monobloc mode?  I have 2 sitting here and hoping to use it as mono bloc mode or even turn the two Chengzhi boards into monobloc.

These should help.  The picture showing the bottom of the PCB indicated 5 marked spots, you just link them together. The picture that displays the top side of the board indicated that in mono mode,  signal input is L and ground only (leave the R pin alone).  For output, just follow the picture.





As a disclaimer, these are information that I obtained from the seller and I have not tried it yet (the boards are on their way).  So please do not held me responsible for any "unfortunate" events should any arise. 

Regards,

[wired4sound]

This seems to be a nice board.  One  guy on the diyaudio forum is using two of these with his minidsp and like them.  This board is designed and made by ybdz (http;//ybdz.taobao.com).  You can actually buy them from the "original designer at TB".  However, the reseller that you are buying from is offering free shipping which is an excellent deal.  Mind you, the shipping charge to send the board to you could cost the vendor the same as he paid for the board!! For your information, the price at TB is about 7-8 US$.  Personally, I always prefer to buy from the "original designer/manufacture" of the product instead of a reseller since they are relatively more willing to support the product regarding questions and queries of the item. Obviously, they know more about the item than a reseller.  Unfortunately, you have to communicate with them in Chinese.  Before I forget, for this board, the inductors used in the output filter is 22 uH, which is more catered towards 8 ohm speakers (does not mean that it will not work with 4-6 ohm speakers).

The "extra" white 3-pin input next to the signal input is for muting and standby purposes and needed to be connected to another unit to be functional, I think. 

I think you will like this board.

Regards,

Thanks for the comment! Glad to hear that someone had tried and liked it.

I guess that is why the cost to me is about $14, seller already built in the charge for shipping. I am in California and postal cost is about $7.

If it indeed does not make the popping/clicking sound and like the SQ, I would like to build a mono. I wonder if the guy from the DIY forum has set it up as mono. Would you happen to know how?

Thanks again!

[wired4sound]

Well... Mine doesn't get warm either with a 12V PS. However, with the boards manufacturer recommended 24V PS the heatsink that came on the blue boards chip does get hot. I believe the sweet spot is 21V. Not sure if a 21V PS will keep chip cooler. Do the 19V laptop PS's keep the chip cool?

The 19V brick I am using does not make the heatsink hot. I can touch it for a very long time and there is barely heat.

It looks like I need to install a heatsink for the board I ordered, if not built in. Hoping to get the heatsink and glue with it. I have not done gluing a heatsink on a chip.

[lo_tse]

Thanks for the comment! Glad to hear that someone had tried and liked it.

I guess that is why the cost to me is about $14, seller already built in the charge for shipping. I am in California and postal cost is about $7.

If it indeed does not make the popping/clicking sound and like the SQ, I would like to build a mono. I wonder if the guy from the DIY forum has set it up as mono. Would you happen to know how?

Thanks again!

I do not think he used it in mono mode.  He mentioned that he has very efficient speakers so no need for more power 

Regards,

[lacro]

I also noticed Hiamplifier added a gain resistorkit to blueboard and changed caps in outputfilter.

Would someone please explain what determines the ideal gain for different input signal sources and speakers?

Here's the resistor pack from Hiamplifier being supplied with his blue board to change gain:

Axial Resistors x 1 Pack [For Master Mode Gain and Input impedance:  20dB/60KΩ, 26dB/30KΩ,32dB/15KΩ, 36dB/9KΩ)]

Thanks...

Lacro

[Markvdv]

re:lacro (what electrolytes does new (hiamp)blueboard pcb have?)
Do you feel you only use first part of your volumecontrol, does soundlevel become loud very quickly? If you lower gain you will have a little more range in your volumecontrol.
Do you feel you mostly use toppart of your volumecontrol? Increasing gain might give you more range in your volume control.
Something like that, but...
Do you feel hiss/hum is a little too loud, lower gain will lower hiss/hum
Do you feel music is little dull, higher gain might give you a little more (a)live sensation

I basicly used it for hiss/hum control and still use first part of volumecontrol, high output source/preamp, I use one 5.6K resistor. Input impedance is higher with lower gain, which means without changing inputcaps you get the effect of larger inputcaps, little more bass (and actually higher in frequency then you might expect). The inputcaps and inputimpedance(gain) form a shallow bassfilter. In some situation you might not notice this at all, but you might feel it is actually a huge difference, depending on room/speakers/music. So if you have a set of gainresistors you could find out if increasing value of inputcaps is something to consider, just by lowering gainsetting. You have to listen quite some time specifically to bass sections befor you change gain to hear if there is a difference and how much of a difference, memory is tricky:)

re:rhing txs once again. I wrote off the Pan. FM cap after listening to it with sure3110, and quite a high value F it was. In 3116's I put in four 680uF FM's a couple of hours ago, first impressions: not harsh like with 3110. Voices seem clearer, more forward, bass is louder but not all bass, real low bass isn't, PinkFloyd "FletcherMemorial" bass doesn't move more air, it is above that frequence. But bass seems better integrated with rest of music. Above voices, cymbals seem a little more back/weaker in the mix, and for now less detailed more like noise/hiss, but will listen to these for at least a week now.

[shadowlight]

Before I forget, for this board, the inductors used in the output filter is 22 uH, which is more catered towards 8 ohm speakers (does not mean that it will not work with 4-6 ohm speakers).

The Soul Superfly that I use are 16ohm speakers?  What value should the output filter be?

[Markvdv]

33uH for 16ohm is closest to 40.000hz filter, if you have redboard with 22uH that will be fine I guess, is similar to 8 ohm speakers with blueboard.

[rhing]

re:rhing txs once again. I wrote off the Pan. FM cap after listening to it with sure3110, and quite a high value F it was. In 3116's I put in four 680uF FM's a couple of hours ago, first impressions: not harsh like with 3110. Voices seem clearer, more forward, bass is louder but not all bass, real low bass isn't, PinkFloyd "FletcherMemorial" bass doesn't move more air, it is above that frequence. But bass seems better integrated with rest of music. Above voices, cymbals seem a little more back/weaker in the mix, and for now less detailed more like noise/hiss, but will listen to these for at least a week now.

I took out the 1,000uF / 25V Elna Silmic II caps on my Sure Electronics TPA3110 amp and replaced them with a pair of 470uF / 35V Panasonic FM caps. I left the single 2,200uF / 25V Panasonic FM on the power supply inputs. The amp sounds smoother, more relaxed and better tonally. On some music like classical with heavy strings, the treble used to almost squeal at higher volumes. It was also a little smeared. Now it's very clean, and there is also less hiss/noise. At $10 a board plus about $15.00 of electrolytic caps and Bourns Ferrite beads as output filters, this amp is a real bargain.

[Markvdv]

The sure tpa3110 is far more sensitive to changing the Ecaps/bulksupply I feel. The 3116 shows some/most of the differences but all in a more controlled manner I feel. Fun thing with the sure3110 is adding caps can result in rolling low basses, far louder then 3116 (haven't tried as much combinations with 3116 yet), (I did put 3110 in 20dB gain and changed inputcaps).

Regarding outputfilter, inductors, speakerloads. Found a graph that visualises effect. Mind you filter used here is for SE amp, If you bridge this SE amp this 4 ohm SE filter becomes an 8ohm BTL filter like in tpa3116 redboard.

[matt_garman]

I took out the 1,000uF / 25V Elna Silmic II caps on my Sure Electronics TPA3110 amp and replaced them with a pair of 470uF / 35V Panasonic FM caps. I left the single 2,200uF / 25V Panasonic FM on the power supply inputs. The amp sounds smoother, more relaxed and better tonally. On some music like classical with heavy strings, the treble used to almost squeal at higher volumes. It was also a little smeared. Now it's very clean, and there is also less hiss/noise. At $10 a board plus about $15.00 of electrolytic caps and Bourns Ferrite beads as output filters, this amp is a real bargain.

Do you think the tpa3116 still bests the 3110?

On the tpa3116 thread over on DIYAudio, there's been some mention about matching the output inductor value to the speaker load.  I.e., there are ideal values for 8 ohm versus 4 ohm speakers.

Does anyone know what the default (i.e. un-modded) ideal speaker impedance is for the Sure 3110 and JY Blue 3116 boards?

I haven't had a chance to compare my 3110 and 3116 again since I posted on it a while back.  But this weekend, I turned my 3110 up more than usual and some of the magic was definitely lost.  I've seen this before with this amp: it's not meant to play loud; at least not with my speakers.  According to the docs, my speakers (Overnight Sensations) are about 83 dB efficient.  The Sure tpa3110 only does 3 WPC at 8 ohms (which is what my speakers are) before the distortion gets pretty big.  My usual listening volume is well under 80 dB, so there's no problem.  But the few times I've tried to crank it, the result isn't good.

Many months ago (more like a year or more), I did compare my then-stock Sure tpa3110 to an older version of this TK2050-based HiFiMeDIY T2 amp with a 300 Watt Connex SMPS power supply.  At lower volumes, the tpa3110 was better, no-contest.  But once I wanted to crank the music loud enough that I could hear it in another room (wife put me on bathroom cleaning duty), and the tpa3110 just sounded awful when the volume was loud enough to be heard in the bathroom.  But I switched over to the TK2050 and got the volume I needed and good-enough sound quality along with it.

So... anyway, I was thinking, I suspect that one's listening levels (combined with speaker efficiency) might greatly affect whether or not you prefer the 3110 or 3116.  Also, the output filter inductor being correctly tuned to the speaker load might make a big difference as well (particularly considering that the general consensus is that the inductor upgrade seems to be the best bang-for-buck mod on the YJ Blue 3116).

[Brad]

With 96db speakers, I prefer the 3110 to the 3116.
Like you said, most likely has to do with fitting the power delivery profile.

[OzarkTom]

With 96db speakers, I prefer the 3110 to the 3116.
Like you said, most likely has to do with fitting the power delivery profile.

Not surprising, majority of the time the lower powered version of any company's amps sounds the best.

[Wind Chaser]

With 96db speakers, I prefer the 3110 to the 3116.

How so?

[rhing]

It's too soon for me to say which amp is better, the TPA3110 or TPA3116. Before I changed the caps in either, I liked the TPA3116. Now it sounds like both are performing optimally. In both cases, I have determined the bass response to have improved using a test CD. But more importantly, the amps have better separation, sound stage depth, more natural and richer tone with a sweeter, cleaner treble. I just went overkill going with 1,500uF and 1,000uF caps on the DC decoupling. I don't know what the optimal capacitance is, and unfortunately, the thru-hole eyelets on these Chinese amps can only take 1-2 desolder/solder cycles for trying different caps before they come off. For now, 470uF seems to work well. If you were to ask me today how I would rank the Texas Instruments Class D amps I've tried so far, this is how they rank:

• Yuan Jing TPA3116 2.0 "blue" amp
• Sure Electronics TPA3110
• ChengZhi TPA3116

In all cases, I added a 2,200uF / 25V Panasonic FM electrolytic cap on the power supply input terminal blocks.

I think it all comes down to matching the best amp with your speakers and your listening preferences.

[lo_tse]

I haven't had a chance to compare my 3110 and 3116 again since I posted on it a while back.  But this weekend, I turned my 3110 up more than usual and some of the magic was definitely lost.  I've seen this before with this amp: it's not meant to play loud; at least not with my speakers.  According to the docs, my speakers (Overnight Sensations) are about 83 dB efficient.  The Sure tpa3110 only does 3 WPC at 8 ohms (which is what my speakers are) before the distortion gets pretty big.  My usual listening volume is well under 80 dB, so there's no problem.  But the few times I've tried to crank it, the result isn't good.

Really, your TPA3110 can drive a 83 dB speaker to usable listening levels?  Then may be I should give it a try with my planar magnetic panels which are also 83 dB and is generally accepted to be very inefficient.  I have been using a YJ red board for a few months now on my second pair of speakers (87dB) and like it.  I was thinking that the red board will not have enough juice to play the panels at loud volume and did not even bother to try. 

Regards,

[matt_garman]

Really, your TPA3110 can drive a 83 dB speaker to usable listening levels?  Then may be I should give it a try with my planar magnetic panels which are also 83 dB and is generally accepted to be very inefficient.  I have been using a YJ red board for a few months now on my second pair of speakers (87dB) and like it.  I was thinking that the red board will not have enough juice to play the panels at loud volume and did not even bother to try. 

I guess it depends how you define "usable".   My application with these particular speakers is sitting on my desk. IOW, very near field. Each speaker is maybe two or three feet from my head. Also, I'm certain most would consider my listening levels fairly low. The room where I use them shares a wall with my three year old's room, and I usually only get a chance to listen when she's sleeping. I used an SPL meter app on my phone once, and the music was around 65 dB.

So, yes, usable for my particular case, but this wouldn't cut it for some.  But then again, for $10, so not much of a gamble if it doesn't work out.

[Brad]

How so?

With the 3110, the midrange was a little more pleasing to my ear.  And at low levels, I felt the balance was better.
The 3116 seemed to need a little more juice to come on song.

Small differences - I like both a lot, especially for the $ and fun involved.

[lo_tse]

I guess it depends how you define "usable".   My application with these particular speakers is sitting on my desk. IOW, very near field. Each speaker is maybe two or three feet from my head. Also, I'm certain most would consider my listening levels fairly low. The room where I use them shares a wall with my three year old's room, and I usually only get a chance to listen when she's sleeping. I used an SPL meter app on my phone once, and the music was around 65 dB.

So, yes, usable for my particular case, but this wouldn't cut it for some.  But then again, for $10, so not much of a gamble if it doesn't work out.

Thanks! Yeah, I suspected one does not need much power using the speaker for near field listening.

Regards