100v. The capacitance is a better match for my speakers. Generally Ti recommends 1uf for 4 ohm and 0.47uf for 8 ohm.
Just one of those lockdown things you get to do just because it's there! But technically should give a better Q to the filter
Just one of those lockdown things you get to do just because it's there! But technically should give a better Q to the filter
I beg your pardon. I wrote the wrong value before......I swapped them to 0.47uf Wimas....more suited to 8ohm speakers.
Apologies!
Apologies!
@Kay Pirinha thanks, I'll look at polar caps to fill the requirements!
@bushellj Good to hear you are getting better sound from an OPA1656. I tried to find these opamps but it seems like no one in my area does them on a DIP8 finished board. So I bought the 1622s. Maybe I'll change it over when I have more time to get those bare boards adapter and find the parts.
You will be surprised. I managed to fit 2 Vishay MKP 1839 (those round ones) into my Lepai. I'm gonna see if I can get some normal rectangular MKPs to fit in the output side to replace those 105J100.
Coilcraft and Wruth inductors are gonna be a tough one to fit. I'll try to find some way.
@bushellj Good to hear you are getting better sound from an OPA1656. I tried to find these opamps but it seems like no one in my area does them on a DIP8 finished board. So I bought the 1622s. Maybe I'll change it over when I have more time to get those bare boards adapter and find the parts.
You will be surprised. I managed to fit 2 Vishay MKP 1839 (those round ones) into my Lepai. I'm gonna see if I can get some normal rectangular MKPs to fit in the output side to replace those 105J100.
Coilcraft and Wruth inductors are gonna be a tough one to fit. I'll try to find some way.
I know that MKP would be better than MKS but the foodprint does not match...
Wima MKP2 1uf is RM5 but 11mm larg!!!
I have them on my TPA3255 2.1 china board... the would not fit on 3e Audio board.
Hi. I also had problems getting the OPA1656 chips on a DIL8 adapter so I am now making my own. I know you are in Singapore but I could ship you a pair !
James.
I wonder about the options for the boxing of all those boards and the thermal/cooling considerations. This is related to my TAS3251, but quite similar to the TPA3255 I see.
All (almost all ?) boards offered have a similar layout: TPA33xx on the top, in the middle, with a large heatsink in top. But then, what do we do ? Put this in a small almost closed box ? Air can't really circulate. Heat builds up inside the box... and thermal dissipation is limited by the box. This layout seems is perfect for TI evaluations boards. But not so much for household integration
There are few designs with the TPA32xx on the bottom. We can then imagine that the case bottom plate would conduct heat to lateral external heatsinks. Or install the boards fixed to the side heatsinks a la "Nelson Pass".
Other options, a "burger" boxing a la doctormord: http://www.360customs.de/wp-content/uploads/2016/03/IMG_8512.jpg
I would be interested in your ideas about how to do it best:
- best boxing of existing boards with the heatsink on top and middle of the board,
- best layout for future projects.
JMF
All (almost all ?) boards offered have a similar layout: TPA33xx on the top, in the middle, with a large heatsink in top. But then, what do we do ? Put this in a small almost closed box ? Air can't really circulate. Heat builds up inside the box... and thermal dissipation is limited by the box. This layout seems is perfect for TI evaluations boards. But not so much for household integration
There are few designs with the TPA32xx on the bottom. We can then imagine that the case bottom plate would conduct heat to lateral external heatsinks. Or install the boards fixed to the side heatsinks a la "Nelson Pass".
Other options, a "burger" boxing a la doctormord: http://www.360customs.de/wp-content/uploads/2016/03/IMG_8512.jpg
I would be interested in your ideas about how to do it best:
- best boxing of existing boards with the heatsink on top and middle of the board,
- best layout for future projects.
JMF
I was thinking about getting a tunnel with 2 boards and a FAN but fortunately you can mount mount a 92mm FAN directly... So i will look for having on each board an 92mm FAN.
Controller by tempsensor on the heatsink.
Will look later for using it with FAN at 5V... Will do thermal image but need to look for a supply for the FAN.
Controller by tempsensor on the heatsink.
Will look later for using it with FAN at 5V... Will do thermal image but need to look for a supply for the FAN.
Attachments
The case should have ventilation hole (top and bottom plates) so the hot air can escape upwards and replaced by cooler air (room temperature).
If you want can look for silent fan and mount on the case, powered by the aux 12v. noctua are very good. Personally I don't think you need a fan if the case is properly ventilated.
If you want can look for silent fan and mount on the case, powered by the aux 12v. noctua are very good. Personally I don't think you need a fan if the case is properly ventilated.
Last edited:
I agree, a little "imagination" and a good ventilated case so as not to need a fan, I made mine with some ITX case (PC case) :
Thanks for your feedbacks.
The box needs an important grilled area on tob and bottom ato get enough airflow.
As DrMordor states, having the chip underside may be more "universal". It looks like it is the way implemented by Hypex with nCore and Purify. The modules are built on a solid metal bottom plate, connected I believe to components that need cooling.
JMF
The box needs an important grilled area on tob and bottom ato get enough airflow.
As DrMordor states, having the chip underside may be more "universal". It looks like it is the way implemented by Hypex with nCore and Purify. The modules are built on a solid metal bottom plate, connected I believe to components that need cooling.
JMF
I’d say it’s important to have an enclosure with ventilation, they are harder to find but worthwhile so your amplifier and power supply don’t overheat.
Below is my layout and ventilated enclosure.
BR
Eric
Attachments
No, DIY Speakers handcraft in France with Ribbon tweeter
(But middle / bass is a Triangle indeed)
When I first listened to "the good the bad and the ugly" from the danish philharmonic orchestra in HD Audio, this is like the orcherstra was in front of me ! I really love those speakers )
An externally hosted image should be here but it was not working when we last tested it.
Last edited: