SOULMUSIC

iTrader: (8)

Hey people. The reason for this thread is to document the building of an "amp rack" of sorts.
I would love to own a couple modern 6 channel digital amps...Zapco etc...but...Right!!

Here's the final approx specs / features it will contain.(in time)
3.1 front stage amp
Class A/B
Wattage(rms) / Impedance Ratings
-8x50 + 1x125 @ 4Ohms
-8x100 + 1x250 @ 2Ohms
-8x50 + 4x100 + 1 x 250 @ 1.5 Ohms stable (Competition Mode)

Frequency response - 5hz - 50khz
THD - <0.08% @ 4Ohms
S\N Ratio - >100db
Damping factor - >200
Input sensitivity - Unbalanced - 100mv - 8.5v
- Balanced - 100mv - 17v
Voltage supply - 10.5v - 15v

Features

-built in 12v Oscilloscope

high-contrast backlight LCD
full auto set up feature
recorder roll mode
user-friendly set-up menu
measurements: rms, dB(rel), dBV, dBm
Direct Audio power measurements
x1 and x10 probe calculation
oscilloscope has 6 display modes
input impedance: 1Mohm / 30pF
connection of internal or external signal
analog bandwidth: 2MHz
sampling rate: 10MS/s
display is 128 x 64 pixels LCD white backlight
vertical resolution: 8 bit
max. sensitivity: 0.1mV
oscilloscope has DVM readout
AC or DC input coupling
power supply: 9-13VDC or 6VAC / 300mA


- 6 Channel Audio Analysis

Provides audio analysis of:
peak power
RMS power
mean dB
peak dB
linear audio spectrum
1/3 octave audio spectrum
auto or manual range selection
peak-hold function
speaker impedance selection
language selection

- Gold plated connectors
- Air cooled
Other stuff maybe or less...things can change during the build, they have 10 times already

Here's some pics of the basic idea and gear I'm working with so far..

SOULMUSIC

iTrader: (8)

Since I am waiting for hardware and money to buy more..lol I do what I can when I can..

- figured out how to join the amps together (threaded rods, rubber washers and bolts)

SOULMUSIC

iTrader: (8)

The gold 4 and 10 Awg connectors I had to work with were too big.. This was alot of annoying work..

SOULMUSIC

iTrader: (8)

So after all of the grinding and filing the burrs. I decided I should make sure they all fit...bah!!! Spade connectors would have saved time over the rings and machining but I wanted the most contact area.

Here's what I ended up with..

SOULMUSIC

iTrader: (8)

Ok, so that works good enough. The amps are old school, hell, just old by now. The gold plating on the inputs need attention, solder joints show some cracks, corrosion. The set screws are mangled.
So I think I'll refurb them as best I can while I do a little modding of the pots and Rca's, grounds etc.

Take them apart clean them up and put them back together after the mods.. This is gonna take a while!!

Colton

Very cool!

SOULMUSIC

iTrader: (8)

Thanks man..

After I got the thermal paste off the 4 channel heatsink with some 90% Iso. I then took apart the other 2 channels and monoblock, I found some differences.

1 heatsink is totally anodized black, thermal paste on all the parts you'd expect. This was the 4 channel. Clean now

2 heatsinks are plain alum. on the contact surface and use tape!! I'm gonna guess its thermal tape, but...

1 heatsink is plain alum. , uses tape, and thermal paste..


Soooo.
I'd love some opinions on some ideas

I need better cooling than " stock"

- repaste it all

- Is it the expensive "paste" worth it? http://www.parts-express.com/pe/show...hermal%20paste

-Sand the anodizing off the contact surface of the one that has it?

-Use tape and regular paste? Although I've never seen thermal tape for sale

What would you do ppl? And what do you think will give the best long term solution??

kevmurray

Sure, the stuff dries out over time and the factories are often cheap with it anyway.

No not really. The stuff from Active is fine.

No don't bother with that. Anodizing is not insulating and you want a flat machined surface to mount to.

Yes. The "tape" is electrically insulating. These isolators used to be made of formica and looked like a thin waffer of plexiglass. I've seen some new types made of paste-impregnated silk and others made of some sort of jelly like synthetic. Many power electronics have heat sink tabs that are electrically live. You should also be careful when working with the power on in case they carry high voltages.

I looked at your drawings and photos but I'm having trouble understanding exactly how you are going to build it. I understand your wishlist and it's a good one. How do you plan to implement the oscilloscope and the audio analyzer? Do you have a background in embedded processing?
I've designed and built a few audio amps from scratch so I may be able to help out. In my last project I used a miniDSP which may help you enormously. The 2in/8out is probably what would interest you most. Even if you are capable of writing your own code and generating the filter coefficients you have to admit it's hard to beat a cheap turn key solution like this.

Anyway this is a cool project, I can't wait to see it unfold.

SOULMUSIC

iTrader: (8)

Wow, love the DSP... outta my knowledge level though for now. I have a xover solution..way more oldschool lol..
I know almost nothing when it comes to electronics Kev...remember the 5 channel?? Still collecting dust waiting for me to learn xovers..lmao
So I'm gonna cheat a bit when it comes to the analyzers and oscope . The analyzers are solder together "kits" and the oscope is a retail panel mount.. Both Velleman..

http://www.apogeekits.com/audio_analyzer_kit.htm
http://www.apogeekits.com/oscillosco...el_mounted.htm

From what I've read about them, its a simple enough install with some help

Know any names of the "tape" I could search for?
Something like this? Can't find anything longer yet. but same idea?
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=055-395

SOULMUSIC

iTrader: (8)

Too, many type of electrical tape!!!
http://www.pleo.com/tape/e_tape.htm