Anybody done this on the blue/black Danzz board? Looks like I will have to remove the heatsink. Also looking for an earth point near pin 17 for the cap.
Bit nervous with this mod as its very fine work but I think it would be easy enough to go back to the pre mod state.
Thank you to sharpi31 and dboy for sharing your findings on using transformers to take advantage of the differential inputs. I think this is the final mod my YJ 2.0 blue amp needs to take this amp to the next level. Although, I am very pleased with how it performs now.
Sharpi, very good idea with those transformers. Is there any DC at the input of the TPA chip? I remember that I was thinking about input transformers with a Tripath 2020, but it has has about 2V at the input.
I have 2 LL1540 here in the drawer, so I would be very pleased to be able to use them finally.
I have 2 LL1540 here in the drawer, so I would be very pleased to be able to use them finally.
Very cool. Can you give link of model and where to buy these signal transformers? Are they big bux?
YJ + speaker protection board
Pardon me if it was mentioned somewhere earlier, but as much as I was searching through this thread haven't seen any solution to the annoying (and undesirable) switching on/off 'POP' on all boards (except of those 'green') with just adding in line one speaker protection board?!
Here's how I did it, simple and not more expensive in total than the green AudioBah's board. Yes, this solution needs extra power, an 12VAC transformer, but the most important is that - works! 🙂
Pardon me if it was mentioned somewhere earlier, but as much as I was searching through this thread haven't seen any solution to the annoying (and undesirable) switching on/off 'POP' on all boards (except of those 'green') with just adding in line one speaker protection board?!
Here's how I did it, simple and not more expensive in total than the green AudioBah's board. Yes, this solution needs extra power, an 12VAC transformer, but the most important is that - works! 🙂
Where can we find that board ? BTW it likely only prevents from pops at power on and off and unfortunately not when the amp breaks down and puts DC on the speaker terminals. That feature would have been the icing on the cake.
There are kit or finished boards on eBay - Audio Speaker Protection Board DIY Components Kit for Stereo | eBay
I'm not sure I understand what do you mean by that underlined?
I have just switched off - pulled the DC adapter out of power, and nothing undesirable happened. Switched back ON and music (through DAC/tube preamplifier) started instantly. Just music - no pops no bumps!
(If that matters) speaker terminals, RCA still not in use, and power cord for YJ board, all in raw-working version, while I'm testing the thing.
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I am affraid if you turn up volume your built in protection TPA3116 will trip. Ebay ad says you need 2 for BTL amp, and these amps are BTL.
OK, now I see, that's true! Not tried to turn up the volume high, not needed for the small room. huh
So, what's the solution - two protectors in parallel?
Or will the lower - 20K volume pot value help. 50K is now in tube preamp.
OK, now I see, that's true! Not tried to turn up the volume high, not needed for the small room. huh
So, what's the solution - two protectors in parallel?
Or will the lower - 20K volume pot value help. 50K is now in tube preamp.
Your speaker - (black) amplifier output is not ground, the protectionboard thinks it is. There is negative voltage on the output, so I guess if it works you will have only positive output and ground to your speakers after the protection board, it is at least not het same as your amplifier output. If it works and keeps working that is ... normal unprotected BTL amp will burn.
OK let it burn
I'm joking 😀 thanks a lot for the insight!
So, what are you actually saying is that nobody here ever tried these speaker protection boards with YJ or other (problematic) boards so far? 😕
The + and - input pins on the TPA3110 & TPA3116 are both biased at +3V. When a single transformer winding is connected between the two no DC current flows, if the bias voltage is identical on the two pins. The Bias is also isolated from the source (connected to another transformer winding) so no need for coupling caps. Someone else rightly mentioned that any difference between the DC bias of the + & - inputs would cause some DC to flow through the transformer, but this will be dependent on the DCR of the transformer winding and will be more or less of an issue depending on the specific transformer used. I've never measured any significant DC bias differences, so haven't worried about this.
The transformers I'm using were 4 for £10 on eBay a few years ago, and I understand that they have an approximately suitable spec for this application. To be honest the cores are quite small so I haven't used them for full line level, but thought I'd give them a go here as the signal voltage (out of my preamp) would typically be much lower than full line. I've no doubt you could do much better, and would look for a decent 1:1 input transformer suitable for 10-30Kohm loads (and add loading resistors to reduce the amplifier input impedance to suit the transformer, if required). I ordered 2x Lundahl LL1540 for £25 each on eBay - I'd be amazed if these weren't a huge improvement over the ones I'm using now.
I have a plan to drive one of these amps with a Vout DAC like the AK4396 with just a transformer between the two devices. Volume would need to be adjusted in the digital domain, but thus may be a price worth paying given the simplicity of the DAC and amp interface. It might be a good simple solution connected to an Apple Airport Express etc, where digital volume control is available and easiest to use anyway.
The transformers I'm using were 4 for £10 on eBay a few years ago, and I understand that they have an approximately suitable spec for this application. To be honest the cores are quite small so I haven't used them for full line level, but thought I'd give them a go here as the signal voltage (out of my preamp) would typically be much lower than full line. I've no doubt you could do much better, and would look for a decent 1:1 input transformer suitable for 10-30Kohm loads (and add loading resistors to reduce the amplifier input impedance to suit the transformer, if required). I ordered 2x Lundahl LL1540 for £25 each on eBay - I'd be amazed if these weren't a huge improvement over the ones I'm using now.
I have a plan to drive one of these amps with a Vout DAC like the AK4396 with just a transformer between the two devices. Volume would need to be adjusted in the digital domain, but thus may be a price worth paying given the simplicity of the DAC and amp interface. It might be a good simple solution connected to an Apple Airport Express etc, where digital volume control is available and easiest to use anyway.
While these aren't technically ideal for the input of TPA amps (being 600ohm rather than 10Kohm spec 1:1 transformers) they should work well, and for the price may be a great option for anyone in the UK:
http://www.diyaudio.com/forums/parts/258748-bbc-ll-252-h12-transformers.html#post3982310
http://www.diyaudio.com/forums/parts/258748-bbc-ll-252-h12-transformers.html#post3982310
No, not that I know of. I am just an old fahioned guy using speaker protection on any amp as it saves woofers. Any amp can break down. If we would know why, where and when we would not need protection 😉
Since these boards are BTL amps the DC protection on standard protetcion boards won't work.
OK let it burn
I'm joking 😀 thanks a lot for the insight!
So, what are you actually saying is that nobody here ever tried these speaker protection boards with YJ or other (problematic) boards so far? 😕
TPA3116 is protected. There are some posts in this long tread, even people using 2 protection boards.
A switch between pin2 SDZ and gnd seems easiest way to avoid any pop, it puts the tpa3116chip in standby/off position. There are some boards doing that, those are even more quiet then the mute pin controlled on/off. Then there are boards doing both, I think the purple heatsink without remote does for example, the remote/display version just uses SDZ and is completely quiet, not a little crack, never. Remote volume control and switching also completely (digital)pulse free, I tried on full power too. Many commercial remotecontrolled amps I owned are failing here, you can hear little pulses through your speakers when using the remote. Not that that is very important, but one would think a $5000 amp designer could have paid some attention to this. The tpa3116 remote designer did or was lucky 😀
YJ Danzz Blue/Black upgraded with Panny OSCON and 3.3uF filmcaps
My Blue/Black is now Blue/Brown/Black with the upgrades. I installed Panasonic 330uF OSCON SEPF caps for the power rails and Panasonic 3.3uF 250V metalized film caps for the input decoupling caps. Had a test listen with the usual test tracks and it sounds very nice. The soundstage, clarity, and dynamics have improved. Quite happy with how low cost this mod has been ($7 including shipping from Digikey) and easy to do too because of the thru-hole design of the Danzz board.
My Blue/Black is now Blue/Brown/Black with the upgrades. I installed Panasonic 330uF OSCON SEPF caps for the power rails and Panasonic 3.3uF 250V metalized film caps for the input decoupling caps. Had a test listen with the usual test tracks and it sounds very nice. The soundstage, clarity, and dynamics have improved. Quite happy with how low cost this mod has been ($7 including shipping from Digikey) and easy to do too because of the thru-hole design of the Danzz board.
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The built-in electronic protection will not save woofers when a fatal error of the chip occurs. Disconnecting the speaker fast when DC occurs at the output of the amp is the best solution. Learnt my lessons with TA2020.
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I was talking about pop in this last post, mostly. Can you predict what will happen if tpa3116 protection doesn't shut down tpa3116 with "Jadrans" protectionboard. Does the protectionboard like negative voltage on ground? Is the protectionboard protected in other words?