Ovation nx-Amplifier: A 100 W class AB Current FeedbackPower Amplifier Build

hifiramr

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After my first DIY Hiraga build. I have done this one, A great design by Andrew c Russell(Bonsai in diyaudio forum) class AB Current Feedback Power Amplifier.which is now very popular in diy community.

The greatest advantage is that everything is documented in a single pdf file supported with diyaudio forum.One can get all details from his blog.

Ovation nx-Amplifier: A 100 W class AB Current Feedback Amplifier

Excellent quality PCB sets are available in Jims audio store.The power supply itself have dc protection and mute delay options.It have some smd components that is very exciting to solder this.I think this is very easy to solder from my and a new level of experience.

Attaching some pictures of the build.

Parts where ordered from element14,diyaudiocraft,diycomponents,shelfkey and theaudiocrafts. I have some parts with me if anybody interested to build.

Beautiful cabinet was customized by Aminder
theaudiocrafts

Power transistor and some components are from Bibin

Coming to Sound:- wow its really awesome performance with my Spendor s3/5 SE speaker using Akido diy tube preamp.Very good details with excellent mid.A complete power amplifier.I have used many amps to drive spendor but not fully satisfied now its perfectly matched with NX.


Enjoying the music after a long break.
 
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congratulations !

But you need the Spendors on a pair of speaker stands to really get it correct.
 
dont think so I have a pair of stands before but this makes not much difference the stands are heavy not light weight.But will be trying to do some wooden diy stand soon.There is no bass port for this one a closed design
 
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Intresting to note

The way you have placed you speaker on the table with the baffle almist
What 3-4 inches from the front edge !!

And you have experienced
No difference???

Intresting....
 
After my first DIY Hiraga build. I have done this one, A great design by Andrew c Russell(Bonsai in diyaudio forum) class AB Current Feedback Power Amplifier.which is now very popular in diy community.

The greatest advantage is that everything is documented in a single pdf file supported with diyaudio forum.

How much did you spend in this whole process?
 
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Intresting to note

The way you have placed you speaker on the table with the baffle almist
What 3-4 inches from the front edge !!

And you have experienced
No difference???

Intresting....

Yes difference will be there when we move away or close to the wall the bass response will show the difference and we can adjust accordingly.As this is not a permanent setup.I will be planning a diy wooden stand for speaker or a diy floorstanding speaker like proac 2.5 clone

How much did you spend in this whole process?

I spend almost 30k for the amp tha cabinet was costly also the transformer but we can restrict it between 20k.Also if sombody want to try it out I have some parts with me.As this is class AB we dont need huge heatsink
 
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the wall is not what im confused about

what confuses me is the response you get because the driver on the front baffle fires on the glass shelf below it

under all circumstances that i know of
the front baffle should be at least along the front edge of the table ( right now the front baffle is almost 4-5 inches off the front edge)
so the driver has no reflections from the base
the response that you will get in this position is what confuses me
 
magma you may be correct because you are very experienced in this,but I cannot see any difference as just getting wonderful sound since this is not my permanent setup I need to work more on speaker positioning.But for sure I will be trying a stand soon.
 
I spend almost 30k for the amp tha cabinet was costly also the transformer but we can restrict it between 20k.Also if sombody want to try it out I have some parts with me.As this is class AB we dont need huge heatsink

30K? I can't believe it. anyway, the heatsinks are an overkill. I think only one of them is more than enough to drive two channels.
 
I have done this because I am a fan of Alcon caps as this is screw type i cannot solder in the board.Also its not too far away from the psu board.I dont think it will effect the sound quality.As my concern was a dead silent on speakers that is very much achieved by his design.
 
I was not talking about effect in sq or anything. It is general rule and good practice reduces emf and rfi and any other noise. And also the esr values of caps are diffused if there is any break in link chain.
 
Only issue I have with my speaker stand which is glass pointed out by Magma I will be removing it with a diy wooden stand soon.About the amp its amazing one mainly the amp is dead silent also there is no oscillation this is what an amp need of mainly.
 
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