800 Watt MOSFET Amplifier Module

[The Saint]

Originally Posted by jombeth

Hello,

I'm interested in your 800 watts amp. however, as an amplifier enthusiast, i would want to build it with myself. So, can you help me by posting or sending the complete circuit with complete details and also biasing, through my email arvin_ksa2000@yahoo.com? I will be thankful to you...

More power!!

Arvin

Hi Alvin

Sorry mate I only sell modules

Cheers

Anthony
Aussie Amplifiers

[WSDS]

The Saint,
How much is the nxV800 power amp. module? I'm building a dual front load 18" subs, i'm planning to make it active.

Thanks
Warren

[The golden mean]

Originally Posted by WSDS

The Saint,
How much is the nxV800 power amp. module? I'm building a dual front load 18" subs, i'm planning to make it active.

Thanks
Warren

Hi warren! Shouldn´t you be able to read this page?

Holton Precision Audio Online Store - Audio Electronics -

[The Saint]

Originally Posted by WSDS

The Saint,
How much is the nxV800 power amp. module? I'm building a dual front load 18" subs, i'm planning to make it active.

Thanks
Warren

Hi Warren

The nxV800 modules cost $579.00AUD each

Cheers

Anthony
Aussie Amplifiers

[Juhleren]

Hi Anthony,

Your nxv800 sure looks the treat :-)

I can see on your website that you have introduced R2 versions of the nxV300 and 500.

Are the changes that these R2´s are based on, in any way similar to some of the attributes of the nxV800 such as possibility for a dedicated VAS supply and less nfb?

Some comments from you on what that can be expected from these R2´s in terms of technical attributes and of course most important how they sound compared to your other offerings would be highly appreciated.

For reference I have a pair of nxV200 signature, so I have first hand knowledge of how they perform in my system.

Also, I have noticed on other amps that routing the speaker return either back to the amp board or directly back to the ground reference between the supply caps can have a significant impact on the audible performance.
- what is your recommendation for getting most out of your amps (speaker return back through the boards or directly back to PS ground ref?)

I´d guess that making the current flow back trough the ground plane on an amp can affect the performance somehow -especially regarding the working conditions of the nfb loop(s)...

best,

[AndrewT]

Juhl,
carefully trace out the route that the speaker current follows from smoothing capacitor through to the amplifier, through the various traces and output components of the amplifier and then the final part of that route to the speaker Hot Terminal.

Where on that route is the point that passes over or very nearby the Main Audio Ground?

Now take your speaker return route to exactly follow the flow current route twisting the speaker return lead with the Hot flow lead for a long as is possible, till you reach that Main Audio Ground.

Now examine the loop area formed by the speaker flow and return wiring. Is it minimised? That is what you need and it reduces the effects of high current flow in the speaker cables on the low level circuits that pass nearby.

[Juhleren]

Hi Andrew,

Thanks for your guidance -its highly appreciated!

My main audio ground is the starground point between the supply caps. The point where the supply leads leave the supply caps is thereby also the point with shortest distance to the main audio ground (if I understood that correctly).

The way I read you, the point for me is to make the speaker return follow the hot speaker lead back to Main Audio ground. If this is correct, it seems that I have two possible extremes; being either to have the hot lead as short as possible (directly from board hot terminal to enclosure terminal) -making the return lead following back to the board and then back to Main Audio Ground. Or Having the return lead as short as possible (directly from enclosure terminal back to Main Audio Ground between the supply caps) -making the hot speaker lead following back to MAG and then to hot terminal on amp board.

The third possibility would of course be to direct both hot and return lead back to the amp board, but to the (speaker return terminal) on the amp and from there making the hot go back to hot terminal on the board and the return thereby connect with the Main Audio Ground through the boards ground lead.

-Any recommendations on which of those two opposites (or routing return back through the board to MAG) that should be best?
(My own guess would be that the amp will be affected by the electrical parameters of the wiring meaning that routing back to amp will provide a better L/C ratio for the amp to chew on)

BTW, I have no noise issues at all so I´m not trying to deal with that. It´s more about getting the best possible sound from the amp and based on experiences with other amps, choosing to direct the speaker return current through the boards (speaker return terminal) opposed to directly back to star ground between the supply caps can have significant influence on the sound. Unfortunately not only for the better in either case...

best,

[The Saint]

Originally Posted by Juhleren

Hi Anthony,

Your nxv800 sure looks the treat :-)

I can see on your website that you have introduced R2 versions of the nxV300 and 500.

Are the changes that these R2´s are based on, in any way similar to some of the attributes of the nxV800 such as possibility for a dedicated VAS supply and less nfb?

Some comments from you on what that can be expected from these R2´s in terms of technical attributes and of course most important how they sound compared to your other offerings would be highly appreciated.

For reference I have a pair of nxV200 signature, so I have first hand knowledge of how they perform in my system.

Also, I have noticed on other amps that routing the speaker return either back to the amp board or directly back to the ground reference between the supply caps can have a significant impact on the audible performance.
- what is your recommendation for getting most out of your amps (speaker return back through the boards or directly back to PS ground ref?)

I´d guess that making the current flow back trough the ground plane on an amp can affect the performance somehow -especially regarding the working conditions of the nfb loop(s)...

best,

Hi Juhleren

The R2 nxv300 and nxV500 are based on the nxV800 module and all of these
modules now share the option of having a dedicated VAS-Input stage power supply and they also share the nested feedback loop.

Regarding the Speaker Ground point, the best option I would suggest would be to connect the Ground point at the speaker GND on the main amp board,
This provides a single GND return back to the main power supply ground, rather than the two return grounds back to the power supply GND.
The signal grounds on the main amp board are isolated via a 10 ohm resistor
from the main ground plane and are connected from this resistor directly
to the main power ground point on the amp board.
So they would not be influenced by the power supply GND currents.

Cheers

Anthony

[Juhleren]

Thanks Anthony,

I will try that

Those R2 revisions sure sound interesting. I guess they also differ in sound then. Any words on how they can be expected to do so?

Are VAS supplies to be the same or slightly higher in voltage than the output supplies, then?
And are there any plans on implementing nested nfb and optional VAS supplies in future nxV200 revisions?

Cheers,

[The Saint]

Originally Posted by Juhleren

Thanks Anthony,

I will try that

Those R2 revisions sure sound interesting. I guess they also differ in sound then. Any words on how they can be expected to do so?

Are VAS supplies to be the same or slightly higher in voltage than the output supplies, then?
And are there any plans on implementing nested nfb and optional VAS supplies in future nxV200 revisions?

Cheers,

With the R2s you can expect sharper focus on the imaging and sound stage.
The nxV200 Signature already has the nested feedback.
For the VAS supplies it is best to have at least 5 volts higher that the main output stage.

Cheers

Anthony