Poor man's multi-amp system?

[bogie]

Okay... There I was...

But you don't really need to know that part...

I've been slowly edging toward building four NSB/Neo half-arrays (going to go 38" high, with 8 NSB each). Thing is, I've been wondering how I'm gonna run 'em... Gonna have to play with adjusting the signals, etc...

Then I had a thought. Also on the list is replacing my Denon 2803 with a real preamp (probably an Outlaw at this point).

The Denon will run in "7 Channel Stereo" mode. Or however many channels you set it as having speakers... So... I can set the thing as a four channel receiver, all "stereo," and feed the right side front to the mids, and the right side rear to the tweets (etc., etc...). Set the delays to zero or whatever, and then...

If I want to pad something, all I have to do is dial it down on the receiver setup!

For starts, this'll mean that I'll have the half-arrays stacked, but hey, I guess I'll have to deal with that... Should easily work to an 8 ohm load for each line.

The thing will theoretically deal with two pairs of fronts, but I'm guessing that the minimum on 'em will be a solid 8 ohm load - Could start to get interesting going toward a 3-way tho...

I'm going to start with a first order on the NSBs, and a 2nd or 3rd order on the tweets.

[mike_e]

> Okay... There I was...

> But you don't really need to know that
> part...

> I've been slowly edging toward building four
> NSB/Neo half-arrays (going to go 38"
> high, with 8 NSB each). Thing is, I've been
> wondering how I'm gonna run 'em... Gonna
> have to play with adjusting the signals,
> etc...

> Then I had a thought. Also on the list is
> replacing my Denon 2803 with a real preamp
> (probably an Outlaw at this point).

> The Denon will run in "7 Channel
> Stereo" mode. Or however many channels
> you set it as having speakers... So... I can
> set the thing as a four channel receiver,
> all "stereo," and feed the right
> side front to the mids, and the right side
> rear to the tweets (etc., etc...). Set the
> delays to zero or whatever, and then...

> If I want to pad something, all I have to do
> is dial it down on the receiver setup!

> For starts, this'll mean that I'll have the
> half-arrays stacked, but hey, I guess I'll
> have to deal with that... Should easily work
> to an 8 ohm load for each line.

> The thing will theoretically deal with two
> pairs of fronts, but I'm guessing that the
> minimum on 'em will be a solid 8 ohm load -
> Could start to get interesting going toward
> a 3-way tho...

> I'm going to start with a first order on the
> NSBs, and a 2nd or 3rd order on the tweets.

why not bi amp the arrays and use say some of these LM3886 kits?
<A HREF="http://www.chipamp.com">http://www.chipamp.com</A>
well you could get the pcb's and order the rest of the parts from his parts list that is what comes with them... seems he is out of parts but not boards. You could just use a single stereo if you didnt want to get to much into the $$. I built one of his and it sounds nice. Im waiting for my w2 to buy the case and rest of the parts i need.

since you said they would be 8ohms could try just not bi-amping at first and go with the just one set of stereo lm3886's and use a avel 160VA-22v/250VA-25v. With the 22v supply you looking at 44watts@1%THD and 50Watts@1%THD with the 25v.

that might be the cheapest way unless you hit up ebay and find matching 2 channel amps... I want to know what you do and how it turns out.
GL
mike

[mikebw]

> why not bi amp the arrays and use say some
> of these LM3886 kits?

I am waiting to build a few of these myself. Aaron here on the forum has said in the past that he plans to offer kits for sale in the near future...

[mike_e]

> I am waiting to build a few of these myself.
> Aaron here on the forum has said in the past
> that he plans to offer kits for sale in the
> near future...
things take time to get lined up to be able to have lots of kits if people want them. I would like to see them too. I would hope he might have the basic kit and then a hi-end kit such as Peter Daniel's does... good clean sound and 38watts sound like a lot more then it is for such a small package.

[mikebw]

I agree.
Hopefully he will offer individual parts as well as entire kits for those of us that might already have some of what we need.

> things take time to get lined up to be able
> to have lots of kits if people want them. I
> would like to see them too. I would hope he
> might have the basic kit and then a hi-end
> kit such as Peter Daniel's does... good
> clean sound and 38watts sound like a lot
> more then it is for such a small package.

[bogie]

> why not bi amp the arrays and use say some
> of these LM3886 kits?

Yeah, but I've already got the Denon, which will put out two channels/side of >80 watts... This way I'll just have to put one filter/channel, and not have to worry about where they meet...

[envisionelec]

> I am waiting to build a few of these myself.
> Aaron here on the forum has said in the past
> that he plans to offer kits for sale in the
> near future...

Not real sure. I'm not offering any "Gainclone" Kits as there are several suppliers on the market already. In my opinion, there are a lot of technical problems with the 'minimalist' design that causes untold headaches with the average kit builder.

Some of the designs I had were lost in a bad sector on my hard disk. :(

Fortunately, I have a hard copy schematic. I also have to purchase a new motherboard and hard disk to replace the aging ones. I think the CPU is fast enough for my work (1.4Ghz), so not much is going into that thing. On the plus side, most of my current designs are on a flashdrive and now I have my computer doing nightly backups to another machine.

So there's a little wait. I figure it's best to have all my previous obligations and distractions OUT of the way first before I embark on a journey of producing a line of kits.

I am already too familiar with the fact that I will be busting tail to maintain my full time job and release these kits.

So here is what I have planned. There's not too many, so think about what you can do with them.

1) Infrared Remote Control passive volume control.

Uses your existing OR universal OR old remote (most supported) to control a motorized volume pot in a little box. The heart of this is a PIC microcontroller that has a learning algorithim to "watch" your remote function and then "remember" what function is has to perform when it sees that code. Of course, you have to press a programming button inside and follow a short list of directions (three steps for UP, three for DOWN).
Typical uses for this include:
a) Subwoofer volume
b) Remote amplifier volume
c) Vintage Receiver remote volume control (use the tape loop)

2) Zero Offset "PointZero" Amplifier

It's not really a "Gainclone" or "Gaincard" at all. It's better. You don't have to fuss with the circuit to make it work right - the first time. Its automatic offset compensation detects minute (or massive) amounts of DC at the speaker terminals, then corrects on a dynamic basis, protecting tweeters and woofers (and your sanity). Based on the LM3886 is the only likeness to the Gainclone.

3) CAR Amplifier Power Supply

Yes, you read that right. A car (12V) to +/-28V @4A power supply. Now, this is useful for ANY Gainclone, my PointZero amp, and many many other kits out there. For the first time ever, a kit for the automotive audio enthusiast is coming.
It has all the protections of a "regular" car amplifier plus speaker protection (optional) which shuts the power supply down in case the amplifier malfunctions or the amp is driven into gross clipping.

On board are two 15V regulators for preamp/signal processing. A preamp/signal processor board is optional, but recommended for clean operation. I have not yet decided to incorporate a crossover or other filtering on this board, because of the great selection of good quality outboard devices on the market.

That about wraps it up for now.

Sorry, I'm not selling individual parts to individuals that have not purchased a kit. Digikey and Mouser are good sources for parts.

[Wolf]

> 1) Infrared Remote Control passive volume
> control.

> Uses your existing OR universal OR old
> remote (most supported) to control a
> motorized volume pot in a little box. The
> heart of this is a PIC microcontroller that
> has a learning algorithim to
> "watch" your remote function and
> then "remember" what function is
> has to perform when it sees that code. Of
> course, you have to press a programming
> button inside and follow a short list of
> directions (three steps for UP, three for
> DOWN).
> Typical uses for this include:
> a) Subwoofer volume
> b) Remote amplifier volume
> c) Vintage Receiver remote volume control
> (use the tape loop)

Definitely cool!

> 2) Zero Offset "PointZero"
> Amplifier

> It's not really a "Gainclone" or
> "Gaincard" at all. It's better.
> You don't have to fuss with the circuit to
> make it work right - the first time. Its
> automatic offset compensation detects minute
> (or massive) amounts of DC at the speaker
> terminals, then corrects on a dynamic basis,
> protecting tweeters and woofers (and your
> sanity). Based on the LM3886 is the only
> likeness to the Gainclone.

Cooler!

> 3) CAR Amplifier Power Supply

> Yes, you read that right. A car (12V) to
> +/-28V @4A power supply. Now, this is useful
> for ANY Gainclone, my PointZero amp, and
> many many other kits out there. For the
> first time ever, a kit for the automotive
> audio enthusiast is coming.
> It has all the protections of a
> "regular" car amplifier plus
> speaker protection (optional) which shuts
> the power supply down in case the amplifier
> malfunctions or the amp is driven into gross
> clipping.

> On board are two 15V regulators for
> preamp/signal processing. A preamp/signal
> processor board is optional, but recommended
> for clean operation. I have not yet decided
> to incorporate a crossover or other
> filtering on this board, because of the
> great selection of good quality outboard
> devices on the market.

That is awesome! "Roll your own" mobile-amplifier! I wish I actually needed one!
Keep us drooling,
Wolf