BGR Mosfet 400w Amplifier KIT

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
I visited the sellers diy amp kits.
There is something big joke here...

700W-RMS with two pair of Sanken BJTs?! ("BGR Blazer St Pro").
SOA?!
700W/4Ohm (150Vpp) from a 70+70=140V supply?

2SK1357 as output devices for his mosfet diy kits?! These are 900V/5A/125W devices for switching applications, aren't good for audio outputs!
SOA?!

BGR Blazer X-10 1000W:
1000W (180Vpp) from a +/-70V supply?!

Etc...
Etc...

Crazy things! Crazy...
 
Thanks for the link Andy...

I am looking for a Kit with very good specs and sound. (Need some fun you know!!!)

I found the specs on the 3020 and 20W is a little bit low for my setup.

There are kits of the NAIM NAP 140 out there. 40W RMS. BJT amp.
Looks nice! Do they sound sweet? Any idle noise?

I have an old AEM6500 amp kit (mono) and a Playmaster 200 series. The AEM6500 has NO noise whatsoever, but the playmaster has always been noisy (bit of an antenna!)

The BGR amp in my first post is based on the Citation 12 but the Mosfet types do look odd.
Is the IRFP240 a better choice for that design? Or some other MOSFET?

I am just looking for 2 more channels for rear speakers to complement my mosfet amps. Both use 2SJ49 & 2SK134.

The Playmaster drives my fronts and the AEM6500 for the centre channel.

Thanks for everyone's help...
 
I had come accross the same kit on ebay. Yeah, the specs look quite ambitious. Even if this thing really only puts out 100W RMS, that's fine by me though. I'm on the lookout for a nice decently powerful kit that's cheap and sounds good.

So what I'm wondering is, what's the sound quality from this thing? I gotta say I'm a bit skeptical.

I was also thinking about this: http://cgi.ebay.ca/TDA7294-Integrat...eZWD1VQQtrksidZp1638.m118.l1247QQcmdZViewItem

Looks like a better choice. I was actually planning to design and build my own using the same chip, but that kit does look decent, and since I don't have unlimited time for this project it would be perfect.
 
I have built 2 of these amps

I have built 2 of these amps and they came out just fine. However, I did not expect 200 wpc amplifiers. They are probably between 50 and 100 wpc. (I would guesstimate around 80 wpc -- more powerful than a Dynaco ST120 but not quite as powerful as a Hafler 200 or Yamaha B2 [amplifiers I own/owned] I have substituted them for a Yamaha B2 (a true 100 wpc) and they held there own. Good sound, quiet and so far reliable. I used a Hammond 182F30 torroid transformer and ebay power supply with six 6800 uF 63v capacitors. I liked the first one so much I built a second. For the money and ease of construction, I think you can't go wrong. Just don't expect 200 wpc amplifier.
 
Couple of questions: I need to replace one 500w BGR board and lost the procedure for biasing, do you have? Also, I have used my own Sanken parts and was wondering if you up graded any parts, ie...0.47 MKT X2 input coupling caps. My right chanel is slightly, but noticablely muffeled.

I my try to locate an amp PCB of better quality. I have two 600va toridsand 16 10,000uf Panisonic caps, plenity of filtering, with the +/- 70v rails.

Thanks Paul
 
BGR Mofet 400 and Blazer

The BGR amps I built were the BGR Mofet 400 (I built 2 of these) and the Blazer (I don't recall the number). The Mofet 400 had a rail voltage limit of 45V DC (I used 42V) and the Blazer around 60V DC (I used 56V) as I recall. [I could be wrong, but I would caution you about going higher.] Both kits came with bias already set. Mofet 400 was a low power amp around 60 wpc. While very competent amplifiers I cannabalized both turning them into L20 amplifiers. The Blazer is a power house and is the equal of my Carver 500x, the Blazer runs some home built inefficient Dynaudio Geminis and the Carver runs NHT 1259 subwoofers. I attenuate the Blazer so the Carver can keep up. Any other amp, I attenuated the Carver. I am very happy with the Blazer and I would buy another if they were available.
 
Blazer Boards

A friend gave me these. He did some biamping with ten, yes ten. He changed out the bias pots. So if they were factory set...I used them to power up my 7ft 3-way line arrays (PICS Included of my work). My brother is an electronics parts buyer and he gave me20 20,000uf 100v Panasonic caps. I also picked up two 600ve torids from ApexJR and added some additional filtering, used 16 total caps. The proof is in the power supply. It did a dam good job and soundede excellent with the LineArrays, they can dip down to 1.5ohms. Now the right side is a bit muffeled in the highs. Did all the swapping to eleminate the easy stuff, but no, it was the amp. I have two extra boards and will rebuild, upgrade before I replace the ones that are in there...MAYBE. If I can not figure out the biasing, I will change out the amp boards.

Hey, I can replace the boards with something else that has 70v rails (can not rember if the voltage is quite that high) from :grumpy: China, modified ofcourse. I put a lot into the amp with the front in Wenga and sides in Purple Wood. There is a board on e bay that will handle up to 100v rails.

Thanks for your help, hope you like the PICs, I need to sale some of these speakers!!!!
Paul
 

Attachments

  • Paul' Wall of Sound.jpg
    Paul' Wall of Sound.jpg
    984.8 KB · Views: 212
  • DSCN0847.JPG
    DSCN0847.JPG
    234.9 KB · Views: 193
  • DSC00343.jpg
    DSC00343.jpg
    1,008 KB · Views: 186
I just tried this amplifier kit, I think this is a cheap amplifier that sounds pretty good. It does not use expensive lateral mosfet , but using vertical mosfet that cheaper and easier to come by, but a hi-fi amplifier that uses vertical mosfet amplifier is not only this. I use it at home and amplifier performance is not bad at all, even quite good compared to mine LM3886 amplifier. And of course, performance can still be improved by replacing the standard components with better quality

An externally hosted image should be here but it was not working when we last tested it.
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.