My whole amp mod and rebuild log Pioneer SA-7300 with 26 pics!

rg12

Member
2010-08-10 3:52 am
After a month and a half of work, im glad to say that im all done!

The amp: Pioneer SA-7300 Vintage Integrated Amplifier

I'll let the pics tell the story...


The front of the amp
[IMGDEAD]http://www.milkbands.co.il/SA-7300/026.jpg[/IMGDEAD]

This is what it used to look from the back
[IMGDEAD]http://www.milkbands.co.il/SA-7300/001.jpg[/IMGDEAD]

Back panel from an inside look
[IMGDEAD]http://www.milkbands.co.il/SA-7300/002.jpg[/IMGDEAD]

Here i started replacing the speaker out terminals and RCA connectors
to gold plated ones
[IMGDEAD]http://www.milkbands.co.il/SA-7300/003.jpg[/IMGDEAD]

[IMGDEAD]http://www.milkbands.co.il/SA-7300/004.jpg[/IMGDEAD]

It was a pretty tough job to fit them in
[IMGDEAD]http://www.milkbands.co.il/SA-7300/005.jpg[/IMGDEAD]

But it was worth it, the volume went up alot (i guess rust wasn't such a good conductor)
[IMGDEAD]http://www.milkbands.co.il/SA-7300/006.jpg[/IMGDEAD]

[IMGDEAD]http://www.milkbands.co.il/SA-7300/007.jpg[/IMGDEAD]

I decided to cancel all the tape record and the unused in and out
connections and leave only the speaker terminals and the RCA in
connections, so i decided to seal the area of the removed connections
and on the way i replaced the old power chord to an RF filtered IEC
inlet and cancel the voltage selector and fixing the amp on 220v.
The voltage selector had the power fuse inside so i installed a separate
fuse terminal for it on the back panel.
[IMGDEAD]http://www.milkbands.co.il/SA-7300/008.jpg[/IMGDEAD]

Making sure it fits
[IMGDEAD]http://www.milkbands.co.il/SA-7300/009.jpg[/IMGDEAD]

[IMGDEAD]http://www.milkbands.co.il/SA-7300/010.jpg[/IMGDEAD]

Painted in black
[IMGDEAD]http://www.milkbands.co.il/SA-7300/011.jpg[/IMGDEAD]

[IMGDEAD]http://www.milkbands.co.il/SA-7300/012.jpg[/IMGDEAD]

The result
[IMGDEAD]http://www.milkbands.co.il/SA-7300/013.jpg[/IMGDEAD]

Rewiring the new IEC inlet and the fuse terminal after cancelling the
voltage selector
[IMGDEAD]http://www.milkbands.co.il/SA-7300/014.jpg[/IMGDEAD]

Now for the real work, i decided to replace all the electrolytic caps to
new ones.
After a long time, i decided on 5 types/brands of caps to install
in certain places in the amp:
Nichicon KG - For the big filter caps, switched from 8.000uF to 10.000uF
Panasonic FC
Elna Cerafine
Elna Silmic II
Mundorf MKP - For the signal path and a few more areas in the amp
Before:
[IMGDEAD]http://www.milkbands.co.il/SA-7300/015.jpg[/IMGDEAD]

Planning...
[IMGDEAD]http://www.milkbands.co.il/SA-7300/016.jpg[/IMGDEAD]

After:
When i replaced the filter caps, the whole amp changed dramatically!
The bass was alot stronger and tighter, everything sounded alot
cleaner and i even got more power.
After recapping each area of the amp, i made a sound test to
hear the differences, that was a great experience.
Everything sounds much better in every way.
[IMGDEAD]http://www.milkbands.co.il/SA-7300/018.jpg[/IMGDEAD]

[IMGDEAD]http://www.milkbands.co.il/SA-7300/017.jpg[/IMGDEAD]

Some of the old caps, almost 40 were replaced
[IMGDEAD]http://www.milkbands.co.il/SA-7300/019.jpg[/IMGDEAD]

All done!
[IMGDEAD]http://www.milkbands.co.il/SA-7300/020.jpg[/IMGDEAD]

[IMGDEAD]http://www.milkbands.co.il/SA-7300/021.jpg[/IMGDEAD]

[IMGDEAD]http://www.milkbands.co.il/SA-7300/022.jpg[/IMGDEAD]

[IMGDEAD]http://www.milkbands.co.il/SA-7300/023.jpg[/IMGDEAD]

[IMGDEAD]http://www.milkbands.co.il/SA-7300/025.jpg[/IMGDEAD]

[IMGDEAD]http://www.milkbands.co.il/SA-7300/024.jpg[/IMGDEAD]
 

rg12

Member
2010-08-10 3:52 am
Thanks man, it was a bit over the price calculated due to expensive
shipping charges and reordering from two websites a few more caps.
So about $170-190.
But it was well worth it, a strong, like new (even better) a amp,
that sound and looks as neat.
 

rg12

Member
2010-08-10 3:52 am
I am surprised more people here don't refurbish / upgrade old stereos.
I added 3 class D channels to an SX-3700 receiver with awesome results.
recapped the power supply and signal caps as well.

nice work

Very nice, i would love to see pics.

There's nothing more pleasing then watching a detailed thread with pics.

I wish there were more of these upgrading threads...
 

Cojun

Member
2010-10-09 10:08 am
Hey RG,

good Job. I own the same amplifter for more than 20 years now and am intended to refresh it a little bit too.
But I miss a schematic diagram (connection scheme) of the amplifter. Do you have such one? Is it possible to get it from you (copy or scan) ?
This would be very great.

Thanks alot

Dan
 
Don't know how I missed this thread the first time around.

Nice work, and a neat upgrade.

I have an SA-7500 with a bad output transistor, and an SX-580 receiver with a bad power chip. Been trying to decide whether to fix them, rework one or both to fit my whim, part the little one out and use the case, or what...

And Shaun is right, Pioneer did a great job styling these products.
 
how did you determine which caps you wanted to replace. I have hatachi hma-7500 that i have done the basic adding an iec and new input and output jacks but i would like to do some internal upgrades as well.
Go the whole hog and "shoot the works" ! Replace 'em all-resistors too-theres gotta be some bodgies in there somewhere and by the time you've rooted them out you might as well have replaced them all anyway.
And, theres the peace of mind that comes with it too.
Do yourself a favour and part with some of your loot dude !!!
Cheers from a tube dude,
Andrew.