Author Topic: HiVi D8.8+ Project  (Read 7982 times)

Offline iondb

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Re: HiVi D8.8+ Project
« Reply #15 on: January 10, 2011, 11:51:13 AM »
Wow, that looks very nice!!!!

Offline Gerhard

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Re: HiVi D8.8+ Project
« Reply #16 on: January 10, 2011, 07:23:09 PM »
Thank you!

Offline Gerhard

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Re: HiVi D8.8+ Project
« Reply #17 on: January 18, 2011, 06:49:26 PM »
I have started building in the amplifier etc.

Here is how far I am:



In the picture you can see the following:

Top left: Relay for switching on/off power to the bass drivers
Below relay: Loudspeaker protection circuit (LPC)
In front of LPC: Active crossover for bass drivers
Below active XO: 8 band EQ from 25Hz to 150Hz
Lower left: Black potted transformer with +-12V PSU for active circuits above it
Bottom center: 300VA toroidal for amplifier
Bottom right: 9V transformer for driving soft start circuit behind it (the SSC limits inrush current into the 300VA TF)
Middle right: Bridge and caps for amp PSU

Some wires and connections are temporary for testing purposes.

What remains to be done is installation of the passive crossovers for the mid and tweeter. The amplifier board is attached to the heatsink which will be integrated into the back plate together with power, volume etc. connectors and controls. The back plate is 5mm think black perspex.


Offline JimGore

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Re: HiVi D8.8+ Project
« Reply #18 on: January 19, 2011, 07:28:09 AM »
Very neat!

This definitely has the "smell" of an ESP project to it  ;)

With the EQ modult built in you are going to get these as close to exactly right as possible - great idea!  You could even sim a Linkwitz transform on the bass using the EQ.

Regards,
Ian.

Offline Gerhard

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Re: HiVi D8.8+ Project
« Reply #19 on: January 19, 2011, 07:30:43 PM »
Thanks Ian.

This definitely has the "smell" of an ESP project to it  ;)

You think? ;) What can I say? I respect the man's work! He does what he claims, the stuff works and it is cheap.

With the EQ modult built in you are going to get these as close to exactly right as possible - great idea!  You could even sim a Linkwitz transform on the bass using the EQ.

That is the idea! And I have one in each speaker! With eight bands of gain and attenuation available per speaker between 25-150Hz (more like 125Hz actually) I have quite a bit of control.

Offline JimGore

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Re: HiVi D8.8+ Project
« Reply #20 on: January 20, 2011, 07:27:46 AM »
Very clever!

I am getting more and more interested in this build as the details are unfolding  ;)

Looking forward to more updates on your progress.

Cheers,
Ian.

Offline Timber_MG

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Re: HiVi D8.8+ Project
« Reply #21 on: January 20, 2011, 08:18:47 AM »
This is no doubt a little monster in the making. And don't discount dowels for bracing (just try and get something out of a hardwood like Oak, birch or beech if you can). The coupling of opposing panels stiffens the enclosure as well as reducing on-axis radiation of side-panel vibrations (think di-pole).

The mid-tweeter combination is superb.
« Last Edit: January 20, 2011, 08:21:06 AM by Timber_MG »