Previous Thread
Next Thread
Print Thread
Rate Thread
Page 1 of 2 1 2
Mitsu Audio Refurb in Calgary AB Area
#385059 11/03/12 11:09 PM
Joined: Sep 2012
Posts: 1,037
Likes: 69
A
connoisseur
OP Offline
connoisseur
A
Joined: Sep 2012
Posts: 1,037
Likes: 69
Hi all,

I am looking to refurb a mitsubishi DA-P20 and DA-A15DC cool preamp/amp combo to original condition. The attenuator knob is noisy and being the unit is 30+ years old and lived in a smoking environment, I'm sure it has lost a little of it's golry. tired

Anyway, I am looking for recommendations for a shop in the Calgary area that is reputable for a refurb and proper test to ensure that the unit is at factory spec output. The unit has great sentimental value to me, so I want to get it looked after right.

Thanks! smile

Re: Mitsu Audio Refurb in Calgary AB Area
aaaaaaaaaaaaa #385062 11/04/12 01:24 AM
Joined: May 2002
Posts: 10,654
shareholder in the making
Offline
shareholder in the making
Joined: May 2002
Posts: 10,654
HC, I don't have any info about shops in the Calgary area, but on the noisy control, note that rotating it rapidly from min to max a couple dozen times(sound off, of course)may clean it enough.


-----------------------------------

Enjoy the music, not the equipment.


Re: Mitsu Audio Refurb in Calgary AB Area
aaaaaaaaaaaaa #385070 11/04/12 07:52 AM
Joined: Dec 2003
Posts: 10,420
J
shareholder in the making
Offline
shareholder in the making
J
Joined: Dec 2003
Posts: 10,420
I've had good experiences with Bestech


Jason
M80 v2
VP160 v3
QS8 v2
PB13 Ultra
Denon 3808
Samsung 85" Q70
Re: Mitsu Audio Refurb in Calgary AB Area
aaaaaaaaaaaaa #385072 11/04/12 02:09 PM
Joined: Jan 2002
Posts: 3,270
connoisseur
Offline
connoisseur
Joined: Jan 2002
Posts: 3,270
Hi,

I've had excellent results using Caig Laboratories Pro-Gold or Deoxit cleaner/deoxidizer spray to clean up noisy attenuators, switches and controls on old gear. The effects seem to last for at least a couple of years before you have to clean them again. Use very little of the spray, just a quick spritz into the control or switch.

Regards,
Alan


Alan Lofft,
Axiom Resident Expert (Retired)
Re: Mitsu Audio Refurb in Calgary AB Area
aaaaaaaaaaaaa #385079 11/04/12 03:04 PM
Joined: Sep 2012
Posts: 1,037
Likes: 69
A
connoisseur
OP Offline
connoisseur
A
Joined: Sep 2012
Posts: 1,037
Likes: 69
Thanks, maybe I'll try to take the case of first and clean up any obvious deposits and see if that helps. I grew up with this behemoth and it was handed down to me from my pa. My first stereo.... not bad. It's a couple years older than me.

and what a powerhouse!! 2 discrete monoblocks at 150wpc. whistle Weighs over 50lbs.

I still have the original hand written receipts and manuals from when he picked them up in 1978. Funny thing is, years later I unknowingly visited the same store (different name) and bought a home theater package. Like father like son, eh!

Re: Mitsu Audio Refurb in Calgary AB Area
aaaaaaaaaaaaa #385080 11/04/12 03:19 PM
Joined: Mar 2012
Posts: 308
Likes: 2
devotee
Offline
devotee
Joined: Mar 2012
Posts: 308
Likes: 2
All sound advice, report back on your results, and good luck.


With out Jesus Christ there can be no Redemption or Salvation.
Re: Mitsu Audio Refurb in Calgary AB Area
Gary Vose Sr #385551 11/12/12 09:17 PM
Joined: Sep 2012
Posts: 1,037
Likes: 69
A
connoisseur
OP Offline
connoisseur
A
Joined: Sep 2012
Posts: 1,037
Likes: 69
Here is where I am at so far. I'm going the DIY clean route first to see if that gets any improvements with the noise floor and crackly attenuator. I am focusing on the pre-amp, as I've routed my modern AVR to the power amp inputs and the output is still pretty clean sounding. Maybe i'll change out the caps at a later date.

Once complete I'll let you know how it worked.

I will of course be blowing the unit out with canned compressed air and spraying the pots and switches with Pro Gold if I can get some.

I Found a really informative vid on youtube about how to do this, so enjoy.

http://www.youtube.com/watch?v=njwi-GwJBzc&NR=1&feature=endscreen

Anyway, here is the unit assembled:



Here is the unit divorced:



Here is the preamp undressed:



Closeups of pots and push button switches:



Closeups of input Selector switch and volume attenuator:


Re: Mitsu Audio Refurb in Calgary AB Area
aaaaaaaaaaaaa #385555 11/12/12 10:28 PM
Joined: Aug 2009
Posts: 6,015
axiomite
Offline
axiomite
Joined: Aug 2009
Posts: 6,015
I wish I could unsee some of that.

Re: Mitsu Audio Refurb in Calgary AB Area
aaaaaaaaaaaaa #385705 11/16/12 03:58 AM
Joined: Sep 2012
Posts: 1,037
Likes: 69
A
connoisseur
OP Offline
connoisseur
A
Joined: Sep 2012
Posts: 1,037
Likes: 69
The DIY refurb complete for now and the results are great. The scratchyness on all dials and master volume are gone.

Noise floor is gone. Sound is clean and open with good separation. It used to sound like blare soup in comparrison.

Great project that is relatively inexpensive if you have old gear. Made a big difference for me. Fun too.

I used Deoxit D5 first then Deoxit Gold after. Each with 24hr inbetween applications to let dry out before powering on. I used a lot I guess. Some boards were soaked by the time I was done.... but that probably did good things anyway. Looks like new inside and out. Highly recommended.

Re: Mitsu Audio Refurb in Calgary AB Area
aaaaaaaaaaaaa #385706 11/16/12 12:33 PM
Joined: Oct 2006
Posts: 6,955
axiomite
Offline
axiomite
Joined: Oct 2006
Posts: 6,955
Nice work. Glad to hear it sounds like new again.
I've been putting off cleaning up an old Technics receiver I've been meaning to clean up mostly for just radio. Maybe this will inspire me.


With great power comes Awesome irresponsibility.
Page 1 of 2 1 2

Moderated by  alan, Amie, Andrew, axiomadmin, Brent, Debbie, Ian, Jc 

Link Copied to Clipboard

Need Help Graphic

Forum Statistics
Forums16
Topics24,939
Posts442,452
Members15,615
Most Online2,082
Jan 22nd, 2020
Top Posters
Ken.C 18,044
pmbuko 16,441
SirQuack 13,840
CV 12,077
MarkSJohnson 11,458
Who's Online Now
1 members (BBIBH), 226 guests, and 1 robot.
Key: Admin, Global Mod, Mod
Newsletter Signup
Powered by UBB.threads™ PHP Forum Software 7.7.4