A New Power Amplifier Prototype

Post Reply
User avatar
Gilbert Y
Advanced Member
Posts: 2592
Joined: Tue May 27, 2003 7:14 pm

A New Power Amplifier Prototype

Post by Gilbert Y » Sun Mar 18, 2018 4:52 pm

I have a chance to convert an old AG8200 to whatever new design I can come up with. Took it to Entracte Audio in Toronto for a comparison with a NSW, NSP and NSL. Here is the picture and I will let George of Entracte Audio do the writing. Because if I have to say anything, all I can say is "it sounds good, mon." :D :) :lol:

Clockwise from 10 O'Clock of the picture. NSL, NSW (top of the stack), NSP and the two chassis new amp prototype without name.
You do not have the required permissions to view the files attached to this post.

User avatar
Gilbert Y
Advanced Member
Posts: 2592
Joined: Tue May 27, 2003 7:14 pm

Re: A New Power Amplifier Prototype

Post by Gilbert Y » Sun Mar 18, 2018 4:53 pm

This new amp is a stereo amp with separate power supply. It is why all the heatsinks are in one chassis and the transformers are in the other.

User avatar
esoxhntr
Dealer
Posts: 508
Joined: Fri Feb 14, 2003 7:39 pm

Re: A New Power Amplifier Prototype

Post by esoxhntr » Mon Mar 19, 2018 3:33 pm

"It sounds good, mon" is likely a bit of an understatement... At first glance, this looks like (and started out as) half of a pair of AG8000 mono block amplifiers. This particular amp was reworked to put out 200 watts as opposed to the standard 140 watts of the regular AG8000. So as Gilbert says, an AG8200 single mono block. You can definitely hear the lineage of the AG8000 series in there, but make no mistake - there are massive improvements. The new version makes the original version sound a little dark and sluggish, and the original version was a pretty damned good amplifier.

What has changed? Well, a few things, most of them to do with re-configuration of the power supply. First, the 6922 tube has made a bit of a comeback. There is only one tube (half of the tube is used for each channel, obviously). It adds a tiny bit of welcome sparkle into the mix. The production version will have a switch to bypass the tube. The gain stages have been revamped, The power supplies have been reconfigured, and multiple KQ circuits have been added to improve the rejection ratio and lower the impedance of each power supply. This results in a blacker background, and that means better contrast with much more vividness and clarity.

The "as yet to be named" production model will be part of the NS series of amps/preamps, and will be available in a variety of physical packages - the whole thing can fit in an NSP chassis if need be, or an NSW chassis with an outboard box, or two equally sized mono block chassis. Price point will likely be at the midpoint between the NSP and the NSI, depending on what customized features are included.

In the end, a re-imagined version of a classic Blue Circle design that sounds superb. I will be voting with my money on this one at some point :wink:

masluck
Advanced Member
Posts: 193
Joined: Tue Dec 23, 2008 12:07 pm
Location: Central New York

Re: A New Power Amplifier Prototype

Post by masluck » Mon Mar 19, 2018 7:45 pm

Very cool!! :D :D :D

I saw that amp in pieces when I was over to Innerkip a few weeks back, and asked Gilbert what he was up to with it. Great to see evolution of the hybrid designs, as I am tube guy at heart (make no apologies for it either :D :D )

Mark

User avatar
Gilbert Y
Advanced Member
Posts: 2592
Joined: Tue May 27, 2003 7:14 pm

Re: A New Power Amplifier Prototype

Post by Gilbert Y » Tue Mar 20, 2018 6:42 am

masluck

I don't know I would consider myself a tube guy from an audiophile point of view. I like the sound effect from tube but don't want the hassle (hiss and noise) and maintenance cost of tube. Especially power tubes. So you will never see me designing a tube power amp. I am using less number of tube because of the cost and the noise. One tube has a nice effect of tube but not the noise of many tubes. In additional, the user can spend the money on buying the best tube in the world because it only take one tube.

masluck
Advanced Member
Posts: 193
Joined: Tue Dec 23, 2008 12:07 pm
Location: Central New York

Re: A New Power Amplifier Prototype

Post by masluck » Tue Mar 20, 2018 9:09 am

Oh I agree...

I think tube power amps are a challenge for a lot of reasons. I have always (except when I was in my teens) had tube preamps and SS amps. To me a blended sound model worked best and still does (at least to these ears). What I was getting at is that at least BC still makes hybrid amps and tube preamps (and continues to support those designs for existing gear from a maintenance perspective) which, to me, is a good thing. In my current setup, I have great flexibility, beyond using cables to tune the sound, with being able to swap in and out various flavors (especially in my BC 2K4sh with the adjustable 6SN7 and SS input stages) as well as rolling the 6DJ8 family in my BC3000. That's the cool part with BC - if you want tubes, you can have them...if you want all SS you can have that too... :lol: :lol: :lol:

Mark (aka masluck)

Post Reply