My TPA3250 EVM is housed in this:
An externally hosted image should be here but it was not working when we last tested it.
It's now running PiCorePlayer (although it shows Rune in the picture)
Also in the case (an old Cossor radio) is:
RPi 3 with an IanCanada Isolator, Waveshare 7" touchscreen, Allo Boss DAC, an ALPS pot, and a Lorlin rotary switch to select the amp input from either the RPi, a BT module or a 3.5mm AUX jack input.
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I recently got a cresnet (Micro-Audio) 47V 600W unregulated SMPS for my TPA3255EVM. Still need to assemble the system. This SMPS seems very well made and is highly regarded in some other audio applications.
For my Wiener PRO (TPA3250) I recently changed to a MeanWell LRS-350-36 from a very large 21V 170W Lenovo brick. I'm finding the MeanWell a little fatiguing even after dialing back the voltage a bit - this surprised me.
Not sure if there's a consensus here yet. Some say it doesn't matter.
BK
For my Wiener PRO (TPA3250) I recently changed to a MeanWell LRS-350-36 from a very large 21V 170W Lenovo brick. I'm finding the MeanWell a little fatiguing even after dialing back the voltage a bit - this surprised me.
Not sure if there's a consensus here yet. Some say it doesn't matter.
BK
I would just make a square out of 4 nice pieces of wood, pre drill and attach the perf aluminium to the bottom side, attach some feet, maybe use some slim strips of wood to make a lower point to attach the perf alu top flush with the wood sides and rear. Steel is better, but not so easy to work with. The chance of me completing anything at all increases dramatically if the materials are cheap and easy to work with. Wood is easy, just shave the pieces clean with the planer and set them in with a bit of oil if you want.
Steel is better, but it just sounds like a lot of work to me. Maybe if you get some copper tape to line the sides with and ground it properly you'll get some faraday effect? Can have a piece of wood with copper tape in the middle, between the PSU and amp modules also?
Steel is better, but it just sounds like a lot of work to me. Maybe if you get some copper tape to line the sides with and ground it properly you'll get some faraday effect? Can have a piece of wood with copper tape in the middle, between the PSU and amp modules also?
Was planning on this: Amazon.com: Fat Daddio's Anodized Aluminum Sheet Cake Pan, 12 Inch by 18 Inch by 4 Inch: Rectangular Cake Pans: Kitchen & Dining
Only thing is, when I first found it, the price was less than $40 USD...
I assume if I RTFM, I will see what I need to do to the TPA3255 EVM to do this. But what else do I need to do/buy to create a 2.1 rig? One of those MiniDSP things?
Not DrM, but, yes, you'll need the drive side of the equation, whether from MiniDSP or elsewhere.
Do note that the 3255 has 2Vrms input sensitivity in SE and 4Vrms (P)BTL when driven in differential (BTL in SE gets a gain of 2, so it remains 2Vrms sensitivity). I think that's a bit higher than the MiniDSP and a lot of soundcards.
Do note that the 3255 has 2Vrms input sensitivity in SE and 4Vrms (P)BTL when driven in differential (BTL in SE gets a gain of 2, so it remains 2Vrms sensitivity). I think that's a bit higher than the MiniDSP and a lot of soundcards.
For the TPA3251 EVM, there is a reset switch on the PCB (S1). If I want an external reset switch (i.e. on my enclosure), what's the best way to go about this? I see the TPA3255 EVM has a pin on J28 just for this purpose, but I can't see the equivalent on the 3251.
Looking at the 3251 EVM schematic, there is test point 13 (TP13 aka "RESETz"), which is directly connected to the TPA3251 chip's pin 18 (RESET pin).
If I simply put a switch between this TP13 and ground, will that suffice? Or will I need something more sophisticated?
Thanks!
Looking at the 3251 EVM schematic, there is test point 13 (TP13 aka "RESETz"), which is directly connected to the TPA3251 chip's pin 18 (RESET pin).
If I simply put a switch between this TP13 and ground, will that suffice? Or will I need something more sophisticated?
Thanks!
I (nearly) completed my second class-D amplifier this weekend, and the first one built around TPA3255 EVM. The chassis and transformer is an old Thule preamp (yes the transformer is from a preamplifier!).
Capacitors is salvaged from the preamp and from the TPA board, as they didn't fit inside the chassis. For the permanent capacitor bank I plan to order a few Kemet PEH169 caps.
As for the sound, first impression on this amplifier compared to another class-D amp I built is a much clearer, "softer" sound and very easy to listen to for extended periods. Excellent midrange and good or very good treble, but a bit weak in the bass.
Capacitors is salvaged from the preamp and from the TPA board, as they didn't fit inside the chassis. For the permanent capacitor bank I plan to order a few Kemet PEH169 caps.
As for the sound, first impression on this amplifier compared to another class-D amp I built is a much clearer, "softer" sound and very easy to listen to for extended periods. Excellent midrange and good or very good treble, but a bit weak in the bass.
Attachments
Is it not available through hifimediy? They sell some Connex supplies. If not, we should ask them to get some. Last time I ordered from Connex it took forever to ship, but that was some years ago.