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AV400v2 - Another 400W Hi-Fi audio amplifier with remarkable sound

First, AV400v2 is much improved amplifier compared to the old AV400 amp. So, AV400v2 is a personal version of the amplifier AV400 or, in other words, how should it look old AV400. If I've sparked your curiosity even a little, then I invite you in this topic to buy even a piece of PCB AV400v2 which includes documentation of the amplifier assembly (including circuit diagram). Documentation amplifier is printed on paper (black and white).

AV400v2 is a (400W - 4 Ohm) compact audio amplifier, Hi-Fi, with good performance, which we subjected to various tests, as you'll see in the videos below. In the two videos below (excuse me, I haven't made ​​a subtitle, but the images are quite suggestive), I tried to highlight what this amp is capable. Unfortunately, Xvid video quality is not the best, maybe even the sound (which is compressed to 192kb/s), but important things you can see see and hear.

AV400v2 is presented in two versions: AV400v2.1 and AV400v2.2 (using the same PCB). AV400v2.1 is MOSFET output transistor and AV400v2.2 is BJT output transistors.

1. TEST AV400v2 - BJT version:
https://www.youtube.com/watch?v=AzytSB64M6M

2. TEST AV400v2 - MOSFET version:

https://www.youtube.com/watch?v=hCpAUlpthC0

In recent years, I have performed various tests, especially with MOS-FET pair IRFP240 and IRFP9240 and, one thing revealed in many technical audio books, indeed, an audio amplifier with MOS-FETs sounds best if he sandwiched one driver pair transistors between VAS amp stage and output stage.
I even made ​​a comparison in this respect. In fact, both AV400v2 amplifier, and GX400 have passed in recent years by some tests - including tests of various topologies (example: Output Triple amplifier...) - and after this I got the version presented.

AV400v2 PROJECT or AV400v2 Documentation contains 10 pages with these "chapters":

1. AV400v2 - Cover
2. AV400v2 - Electrical diagram v2.1 and 2.2
3. AV400v2 - List of electronic components
4. AV400v2 - Indications for operation amplifier
5. AV400v2 - All Layers PCB
6. AV400 v2 - PCB Copper Top
7. AV400 v2 - PCB Copper Bottom
8. AV400 v2 - Drill Info


DOCUMENTATION (printed black and white) is valid in English.


PCBs prices are as follows (PCB size = 216 x 79 mm) :

1 pcs. PCB AV400v2 = 19 USD (includes printed above project to help in assembling the amplifier).

2 pcs. PCB AV400v2 = 36 USD (two pieces include with printed project mentioned above, to assemble the amplifier)

Who buys more than two pieces, the price is 17 USD/pcs. PCB.

I have available built units in two forms (without the heatsink):

a) fully assembled at the price of 85 USD / piece (see pictures below - in this moment only one piece available with MOS-FET).

b) semi-assembly built units - price of 82 USD / piece (I currently only available 4 pieces but depending on demand, I can assemble some extra).
WARNING! semi-assembly built units isn't soldered output transistors, drivers and bias transistor. So, these components will come separately along PCB. After that, depending on how the PCB clamping the heat sink, you have glue them.

Payment can be made via pay-pal at:

tehnium[dot]azi@gmail[dot]com

For more details please contact me via private messaging diyaudio.com or via email: donpetru@gmail[dot]com

AV400v2 amplifier needs 1.2Vrms on the input in order to deliver nominal power. Supply voltages are +/-(40 ... 80)Vdc.
 

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Last edited:
Av400v2 Is 400W / 4 ohms.

How does it compare to a good high end power amp?
It is an amplifier that works very well on low impedance, the sound is very balanced and dynamic; av400v2 amplifier is protected against overloading and short circuit on the output. I don't know what else I can tell you but has a amazing sound. Try it.
 
Sorry, these videos are long, in different language and without index.

Can you provide sheet with basic technical specification?

Also THD measurements should be done at least on the sound card if not audio analyzer. Resolution of used scope is not adequate for THD amplifier measurements.
 
AV400v2 Basic technical specification:

Typical class of amplifier operation: AB;
Supply voltage: +/-40Vdc...+/-80Vdc.
Power Output = 400 W - 4 Ohm; ~200W - 8 Ohm
THD % = <0.1% / 400W.
Input Impedance = ~ 22K;
Input sensitivity to achieve maximum power output: 1.2Vrms/22Kohm.
Slew Rate => 20V/us (theory behind simulation = at least 35V/us).
Audio Amplifier efficiency: ~73%.
Signal-to-Noise Ratio: better than 100dB.

Regarding the THD measurement, indeed PicoScope software used for these measurements is not the best choice. In fact, even in the video say it, but not in english. However, measurement of THD that I made ​​are strictly informative, ie to form an idea of ​​what can amplifier. If I had a PicoScope on 16bit, things were different but, unfortunately, I own one 8 bit.
Maybe some buyers who have a device to measure THD much better. We'll see.
 
Design looks interesting but......

I purchased several PCB's for the BX400 Amplifier. I need Bill of Materials
and a larger schematic for the two possible versions of the BX400. I need this
information, in order to build this amplifier.I assumed when I purchased the
PCB's that this information would be included with the PCB's. Nothing extra
was included with the PCB's. A BOM and larger schematics should be standard
when you purchases PCB's. Especially when this information is not included
on diyaudio.com.:mad:
 
Another pss amplifier

Hello Donpetru
greetings i want to try this short circuit protection as shown in your amplifier is this a tested schematic and hows the performance of the short circuit protection
warm regards
Andrew:)
 

Attachments

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2 pcs. PCB AV400v2 = only 25 USD with documentation included (chapters 1 to 4 included).

!!!!!!!!!!!! Ship cost is about $10 for users from the European Union. !!!!!!!!!!!!!!

I have available built units in two version (without the main heatsink):

a) fully assembled at the price of 78 USD / piece (in this moment only one piece available with MOS-FET).

b) semi-assembly built units - price of 75 USD / piece (I currently only available 4 pieces but depending on demand, I can assemble some extra).
WARNING! semi-assembly built units isn't soldered output transistors, drivers and bias transistor. So, these components will come separately along PCB. After that, depending on how the PCB clamping the heat sink, you have glue them.
 
Last edited:
Unfortunately, there are no more PCBs available for sale.

With this post, I tell you that the AV400v3 was developed a few years ago, but all the PCBs were then sold in Romania. For this reason I have not opened a topic here with AV400v3. But who wants to see what it looks like "v3" can access the following topic:
AV400v3 - amplificator audio Hi-Fi de 400W - 4 Ohm - Produse - proiecte Tehnium Azi - Portalul Tehnium Azi

The big difference between AV400v2 and AV400v3 is that the AV400v2 has a double end stage on the output and the AV400v3 has a triple end stage on the output.

The .pdf format documentation is for a fee and costs only 10 Euro / for AV400v2 and 10 Euro / for AV400v3.

If you want to purchase the documentation you can do this by donating for example 10 Euro through the "Donate" menu on the Tehnium Azi website or by accessing the following link:


Donate

After sending the payment, send me a private message mentioning the name of the documentation (AV400v2 or AV400v3). If you want both documents, they cost 20 Euros.
Therefore, the documentation in PDF format contains the electronic diagram, the list of parts and pdf pages that you can create using the PnP DIY method - PCBs.