• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

building a TPA3255 260-2-29A, and need some guidance

nick650

Member
Joined
Dec 25, 2023
Messages
5
Likes
0
Design goal: 200 rms per channel by four channels (want to be equal or better than my class AB amp), within the quality realm of a Buckeye amplifier, while being lower cost. I plan to have a four channel amplifier.

Location: USA

amplifier: 3e-audio-tpa3255 (have to wait roughly a month to get it from France) times two

Speakers: custom built 4ohm load times four

Power unit: https://micro-audio.com/store/product/smps1ks-pfcr2/

Would I be better off using a 48 volt vs a 50 volt main rail despite the max being 51?

Does this look like the right power supply for the job? What case might fit this (smaller the better)?

PS: First time amp builder

Thanks!
 
Last edited:

antcollinet

Master Contributor
Forum Donor
Joined
Sep 4, 2021
Messages
7,673
Likes
12,932
Location
UK/Cheshire
Design goal: 200 rms per channel by four channels (want to be equal or better than my class AB amp), within the quality realm of a Buckeye amplifier, while being lower cost. I plan to have a four channel amplifier.

amplifier: 3e-audio-tpa3255 (have to wait roughly a month to get it from France) times two

Speakers: custom built 4ohm load

Power unit: https://micro-audio.com/store/product/smps1ks-pfcr2/

Would I be better off using a 48 volt vs a 50 volt main rail despite the max being 51?

Does this look like the right power supply for the job? What case might fit this (smaller the better)?

PS: First time amp builder

Thanks!
Check out this thread by @danibaun

He has a fair bit of experience building amps with these modules. I'm sure he'll be happy to help there.
 

brunes

Active Member
Joined
Jun 7, 2023
Messages
123
Likes
140
For the Micro Audio SMPS I took the SMPS630-SO at 51V, its unregulated and can drop. As mentioned above there is information in the other posts

The SMPS630-SO with +51V will work perfectly, even its unregulated it may drop to 47VDC under 400W load.

Its also dependent on your mains voltage as I understand:
Please see below output voltage at AC input and make up your mind based on it. I'm in Switzerland and its 230 V so I'm actually getting 48.5 V (I think).
AC InputDC Output
24050.44
23549.3
23048.5

You can email Micro Audio, Sami is super helpful.

I used the Modushop cases and got them to drill the holes (and tap the holes) not the cheapest but maybe the easiest.. (they are a bit tricky to earth as they are anodized). Danibaun is the master of making these amps, take a look at his posts...

I shared a list of the parts I ordered with someone else, if that's interesting or useful I can share it.

Good luck!
 
OP
N

nick650

Member
Joined
Dec 25, 2023
Messages
5
Likes
0
For the Micro Audio SMPS I took the SMPS630-SO at 51V, its unregulated and can drop. As mentioned above there is information in the other posts

The SMPS630-SO with +51V will work perfectly, even its unregulated it may drop to 47VDC under 400W load.

Its also dependent on your mains voltage as I understand:
Please see below output voltage at AC input and make up your mind based on it. I'm in Switzerland and its 230 V so I'm actually getting 48.5 V (I think).
AC InputDC Output
24050.44
23549.3
23048.5

You can email Micro Audio, Sami is super helpful.

I used the Modushop cases and got them to drill the holes (and tap the holes) not the cheapest but maybe the easiest.. (they are a bit tricky to earth as they are anodized). Danibaun is the master of making these amps, take a look at his posts...

I shared a list of the parts I ordered with someone else, if that's interesting or useful I can share it.

Good luck!
I'm in the USA, and ya, those cases are almost the price of the project! Thank you for the insight.
 

MCH

Major Contributor
Joined
Apr 10, 2021
Messages
2,649
Likes
2,253

somebodyelse

Major Contributor
Joined
Dec 5, 2018
Messages
3,754
Likes
3,051
diy audio store has some cases in the US... still need to make some holes though
https://diyaudiostore.com/collections/chassis
They're a Modushop reseller, IIRC more cost effective than buying direct if you're in the US. Last I looked they also offered machining and printing if you don't have the capability yourself. I don't know whether that part is done by Modushop or locally.
 

somebodyelse

Major Contributor
Joined
Dec 5, 2018
Messages
3,754
Likes
3,051

Leaning towards this power supply. Seems just about the max output for my requirements, and is much cheaper to boot.
Note the need for additional heatsinking or a fan for rated output. Having said that, music often provides significant derating as average output is a fraction of transient output. This comes back to the old argument about FCC power ratings vs. real world use, and manufacturers that include fans that only ever come on during FCC style tests.
 

daniboun

Major Contributor
Joined
May 2, 2020
Messages
1,879
Likes
2,196
Location
France (Lyon)
Hi,

As you know I shared my 3E Audio and Sylph Audio projects on ASR. The links are in my signature.
For the case, if you go with a Micro-Audio PSU, I recommend this one, It fits perfectly with the 3E Audio + Micro Audio combo


The problem being that my projects have toured Europe and Audiophonics has sold almost all its stocks... Patience will be required)
I don't know if you plan to drill the back alu. panel yourself? But if this is the case, equip yourself with a 22mm drill bit if YES, get this one :

Drill tool

Regarding the PSU, since I tested almost all the PSUs on all of my TPA325X projects (Morsun / Meanwell, Micro-Audio, Audiophonics PFC, Connex, Custom LLC and others). 95% of these PSUs are regulated, only the Hypex and Micro-Audio PSUs are unregulated.
Without supporting measurements unfortunately... I continue to affirm that the Micro-Audio PSU brings something to the listening experience that I cannot feel with the other PSUs.

On the other hand, here is the FFT of the Micro-Audio PSU VS Hypex, which are unregulated and therefore comparable. The Hypex PSU has one of the lowest ripple on the market (85uVrms) Which leads me to think that the Micro-Audio PSU is very efficient!

In the audible band, the Micro-Audio is better.
From 120Hz down to 2kHz the spurious tones are less significant on the Micro Audio as well


index.php



Considering the facts: 3E Audio modules have a very capable PSSR, so any PSU with an acceptable ripple should do the trick.
In all cases, you will have to consider the choice of the power of the PSU in relation to the impedance of your speakers! This has been discussed in my shared projects.
 
Last edited:

daniboun

Major Contributor
Joined
May 2, 2020
Messages
1,879
Likes
2,196
Location
France (Lyon)
Check out this thread by @danibaun

daniboun ) not danibaun ))))) :)
 
Top Bottom