Ideas/advice TPA3255 project

[Bearman]

Yep, it's a little large for that case. I use a 2U rackmount and it's plenty of room

 

[daniboun]

Yep, it's a little large for that case. I use a 2U rackmount and it's plenty of room

I will do without a volume controller lol

 

[ElliJ]

The green 10k DACT Type SMD Stepped Attenuator 21 step from eBay arrived. They are better than the brown ones I got from Audiophonics. The green ones cut the sound at min volume and the lower steps are a bit closer giving more control at lower volume. Sorry about the brown and green but I don’t have more information to give.

I rebuilt my amp with a 3eAUDIO TPA3251, it sounds as good as the 3255 except at higher volumes then it produces a bit more noise. I would recommend 3255 over the 3251.

I have started my new project. I have a larger case and have installed my Douk 400w smps and 3eAUDIO TPA3255. I have drilled the mounting holes for a Khadas Tone Board DAC but have not got one yet. It is wired up with a selector switch, an ON-ON type with 6 pins. I have fitted a usb c panel mount extension lead for the DAC. I forgot to fit a female to female rca for a coax input for the DAC I case I need it in the future. I am also waiting for a power switch. I got a pair of rca a plugs that have screw terminals to for the DAC’s output and connected them to the selector switch..
I was not sure what to do with all my negative/ground wires I ended up soldering 3 left and 3 right wires together and then heatshinking the connection. That is 2 from the inputs and 1 from the pot per channel. It sounds ok and selector switch works without producing any noise through the speakers which was a worry.

My soldering has improved a lot. Just tinning both things being soldered together made most of the difference.

I will post some pictures as soon as I finished.

 

[daniboun]

The green 10k DACT Type SMD Stepped Attenuator 21 step from eBay arrived. They are better than the brown ones I got from Audiophonics. The green ones cut the sound at min volume and the lower steps are a bit closer giving more control at lower volume. Sorry about the brown and green but I don’t have more information to give.

I rebuilt my amp with a 3eAUDIO TPA3251, it sounds as good as the 3255 except at higher volumes then it produces a bit more noise. I would recommend 3255 over the 3251.

I have started my new project. I have a larger case and have installed my Douk 400w smps and 3eAUDIO TPA3255. I have drilled the mounting holes for a Khadas Tone Board DAC but have not got one yet. It is wired up with a selector switch, an ON-ON type with 6 pins. I have fitted a usb c panel mount extension lead for the DAC. I forgot to fit a female to female rca for a coax input for the DAC I case I need it in the future. I am also waiting for a power switch. I got a pair of rca a plugs that have screw terminals to for the DAC’s output and connected them to the selector switch..
I was not sure what to do with all my negative/ground wires I ended up soldering 3 left and 3 right wires together and then heatshinking the connection. That is 2 from the inputs and 1 from the pot per channel. It sounds ok and selector switch works without producing any noise through the speakers which was a worry.

My soldering has improved a lot. Just tinning both things being soldered together made most of the difference.

I will post some pictures as soon as I finished.

Looking forward to see the final result.
As per TI recommandations, the PGA2310 works fine with the TPA32XX
A choice to consider for a Volume control with some ALPS on it :

 

[ElliJ]

Hey Daniboun. This is the new 10k DACT Type SMD Stepped Attenuator 21 Step I am using. I am really happy with this pot, if I wanted to remote control the volume I would look at volume controllers.

My DAC and coax RCA arrive sometime today so I should finish the amp tonight.

I have Audirvana on my Mac, it has an excellent remote app so I won’t need to have a tv or monitor on when I listen to music. It is supposed to be the best music player out there!

 

[daniboun]

Hey Daniboun. This is the new 10k DACT Type SMD Stepped Attenuator 21 Step I am using. I am really happy with this pot, if I wanted to remote control the volume I would look at volume controllers.

My DAC and coax RCA arrive sometime today so I should finish the amp tonight.

I have Audirvana on my Mac, it has an excellent remote app so I won’t need to have a tv or monitor on when I listen to music. It is supposed to be the best music player out there!

Thanks for the feedback )
Let us see when it is finished now. Take care

 

[ElliJ]

Amp MkII

Here is my second amp. It has the same 3eAUDIO TPA3255 amp and Douk 400w 48vdc SMPS. The case is bigger and from Audiophonics. The DAC is a Khadas Tone Board and I used a usb c extension lead that needed a slight modification. The wood on the front is zebrano, oak might have been better to match the tv stand. The DAC is plugged into my Mac Mini 2010 and I’m running Audirvana. The screenshot is of the Audirvana remote on my iPhone, I also tried the android version of the remote which worked too. Audirvana has Tidal so I am using a trial account for that. I am very pleased with my amp and with the Mac and remote it is everything I wanted when I started this project. The Digital Audio Player was very good (iBasso DX160) but could not do a wireless connection to the amp. Using the Mac was my original plan but the DAC was £100 and I think Audirvana is £80 (I’m using a trial at the moment). Apart from a couple of cosmetic changes I would like to make (power switch and selector switch) it is what I wanted.

Almost forgot to mention that the DAC should have a coax input too, I did not plan for this or I would have shifted the USB port over a bit. I have the bits to install the coax input at a later date (female to female panel mount rca and a 20cm rca lead).

 

[daniboun]

Here is my second amp. It has the same 3eAUDIO TPA3255 amp and Douk 400w 48vdc SMPS. The case is bigger and from Audiophonics. The DAC is a Khadas Tone Board and I used a usb c extension lead that needed a slight modification. The wood on the front is zebrano, oak might have been better to match the tv stand. The DAC is plugged into my Mac Mini 2010 and I’m running Audirvana. The screenshot is of the Audirvana remote on my iPhone, I also tried the android version of the remote which worked too. Audirvana has Tidal so I am using a trial account for that. I am very pleased with my amp and with the Mac and remote it is everything I wanted when I started this project. The Digital Audio Player was very good (iBasso DX160) but could not do a wireless connection to the amp. Using the Mac was my original plan but the DAC was £100 and I think Audirvana is £80 (I’m using a trial at the moment). Apart from a couple of cosmetic changes I would like to make (power switch and selector switch) it is what I wanted.

Almost forgot to mention that the DAC should have a coax input too, I did not plan for this or I would have shifted the USB port over a bit. I have the bits to install the coax input at a later date (female to female panel mount rca and a 20cm rca lead).

Nice work and much better.
I love the Zebrawood veener, my snare drum uses the same kind of wood )
Everything seems better organized and ventilated in the case

 

[ElliJ]

Thank mate

 

[ElliJ]

I’ve been listening to lots of music with Amp MkII. I had read a lot of reviews about the Khadas Tone Board and they were not wrong. The sound quality is amazing and compared to my using my DX160 DAP (which is also very good) it has a more analog quality to it. It could be that the Audirvana music player I’m using is also adding to the sound.

3eAUDIO TPA3255 + Khadas Tone Board + Audirvana = Excellence

Next I will be retiring my Aviano 1 speakers and replacing them with a pair of Elac Debut Reference DBR-62. Perhaps next month if I can find £499.

 

[ElliJ]

Time For A Change

I have been very pleased with the amp I made but after living with it I want to make some changes. I don’t use the volume, I use software volume control and the analog output of my tv. I recently tried a Raspberry Pi 3 running Volumio with a usb to my Khadas DAC. It can still use Audirvana as it will network stream to Volumio. I have been trying to work out how to connect my TV to Volumio but I can’t. I can connect my TV to my Khadas DAC if I get an Analog to Digital converter with a coax output. This will give me volume control from the tv and the DAC will switch to coax if it gets a a signal from the coax giving it priority. I can limit the volume and set the start volume in Volumio.

I plan to make an amp without a volume. I have a new switch and relay for 240vac. A 5vdc 5amp psu for the Raspberry Pi 3, Khadas Tone Board DAC and an Analog To Digital Converter. It will use my 3eAUDIO TPA3255 and Douk 48vdc 400w SMPS.

When I turn on the amp I will have to wait about 30 seconds for the Pi to boot. Then using the Volumio app on my phone play music from a micro sD on the Pi. I can also network stream to Volumio from Audirvana on my Mac. If I turn on my Samsung Smart TV I can convert the 3.5mm analog to a digital coax signal, this takes priority in my DAC over usb and then switches back when there is no coax signal.

I think this will be an improvement. It will be more user friendly. Losing a selector switch and a volume pot should improve sound quality (the tv sound quality could be worse).

 

[ElliJ]

My plan for a digital input for my DAC from my TV with volume control worked but the TV produces too much noise and when the amp is at full volume it is too noticeable. If I didn’t need to control the volume this would not be a problem as I could get the audio from a HDMI.

 

[audio_tony]

<snip> I was struggling to solder to the RCA sockets and speaker terminals even with new lead solder, I need some practice.

<snip>?

If you're using lead free solder, throw it in the bin and buy some 60/40 lead solder instead. It flows so much better and will give you lovely shiny joints too.

I could only find this one on Ebay at the moment - they also do a 500g reel - I highly recommend the 'Cynel' brand.

Just ensure you work in a well ventilated area when soldering.

 

[bushellj]

If you're using lead free solder, throw it in the bin and buy some 60/40 lead solder instead. It flows so much better and will give you lovely shiny joints too.

I could only find this one on Ebay at the moment - they also do a 500g reel - I highly recommend the 'Cynel' brand.

Just ensure you work in a well ventilated area when soldering.

I think the main problem with lead is if it enters your system so try not to eat it !

 

[ElliJ]

I realised lead free solder was not very good and replaced it after getting advice from this forum. The thing I learned about soldering is that I need to tin both things being soldered together, especially if one of them has a heavier terminal.

 

[ElliJ]

I have another solution for getting tv audio to my amp. If I plug a usb tv tuner into my Mac the picture would go to the tv and the audio would stream to my amp via the Raspberry Pi then the DAC. I can’t believe getting tv audio to an amp with volume control and decent sound quality is so difficult !!!! The Mac usb tuner is about £40, not going to get one for a couple of months.

 

[bushellj]

I have another solution for getting tv audio to my amp. If I plug a usb tv tuner into my Mac the picture would go to the tv and the audio would stream to my amp via the Raspberry Pi then the DAC. I can’t believe getting tv audio to an amp with volume control and decent sound quality is so difficult !!!! The Mac usb tuner is about £40, not going to get one for a couple of months.

Hi ElliJ.

I have exactly the same problem. I get good quality sound from the TV via an optical output but no way to control the volume - at least with a remote control.

 

[ElliJ]

Yeah it is a real pain. The usb freeview tuner is the only solution I can see. I stream Netflix through my Mac and the sound is good but it doesn’t go through the tv. If you have a pc these tuners are cheaper.

 

[Rick PA Stadel]

Glad you're *on the mend* on the soldering (leaving the Pb-free to the professionals) front!

Another tip: Start with a substantial mechanical connection, then initially apply heat only to the heavier component (of the joint), then you may not always need to pre-tin the parts. Not only saves time, but insulation melt-back, too (if you're soldering insulated wires). Of course, the leads can't have been lying in the bottom of the odds-and-ends drawer for years and years. Keep a little swath of 3M ScotchBrite (IIRC) handy to knock the oxide off, if the part came out of deep storage.

I sure share your pain with the mediocre TV sound. Guess that's what we get for getting the cheapest one with no RCA's -- S/PDIF out is all ours has, too.

Cheers

 

[bushellj]

Yeah it is a real pain. The usb freeview tuner is the only solution I can see. I stream Netflix through my Mac and the sound is good but it doesn’t go through the tv. If you have a pc these tuners are cheaper.

99% of our TV watching is done through an Amazon Stick - even live TV at times but more often time shifted ! We just take the sound from the optical output of the TV but this means that all volume control and any other processing has to be performed by the amplifier - hence our current use of a small Denon Amplifier that has Optical in and a remote control ! This still sounds 100% better than the TV Speakers !

Would love to replace this with a TPA325x Amplifer but really need one with Optical input and remote control. No one has yet come out with anything suitable and the biggest issue for this type of combination is that they tend to be built to rather low consumer standards and Sound Quality is a very secondary requirement !!

So we end up with a pile of boxes - Optical to Analog converter, Pre-Amp with Remove Volume Control and then the main amplifier. Not very wife friendly when installed in the Sitting Room !!!!!