Please get the word out that Sunfires need to be serviced. If they blow smoke/catch fire the service becomes more expensive - if it's even repairable. Last year, someone sent me a burned up unrepairable TGA-5400. Gorgeous, rare amplifier...gone. So I think it's time for a reality check. Many Sunfires are too old to gamble with. They have substantial power and self-destruct rather violently - more so than I think people expect. 

Also, be wary of local repair shops. Sunfires are not easy to work on (even we have to use specialized equipment) and most techs out there do not understand how they work. So it's also common for us to get Sunfires that were not repaired correctly from local shops.

'The guts just come out and go right into the new chassis...'

Ha!!!!!

It wouldn't be too bad if the transformers could just 'unplug' but they don't. Their wires travel everywhere...and that's real problem. There's no room for error - the wire lengths are precise. 3 transformers - each with 8 to 20 wires. All rivets have to be drilled out. All RCA jacks need to be replaced. The thing needs a severe cleaning and polishing. And the worst part - HUMAN HANDS.

Previously worked on and it doesn't work. Worst problem ever.

I'll need encouragement because I really want to say NO.

A typical dirty and rusty specimen!

Decent shape. No severe burning so that's a great start.

Tear down. Lots of dirt. I will take care of that rusty fan grill, and install a new quiet fan and turn down the speed to make it QUIET.

Chassis cleaned up and tested. Had to replace some bad transistors. Typical.

An LED sensitivity switch was requested, so I'm cutting one out here:

Everything cleaned and rebuilt!

New fan and restored grill:

All back together:

Best sounding 750W per cannel amp ever!

C-4000

C-1

And of course it has a blown channel...it's rare to work on a CG and it NOT have a blown channel.

The unit was in dire need of service. Old, crusty, and very dirty.

Top of unit:

Near power switch and primary fuse:

Taken apart:

I removed most of the screws and derusted them, then cleaned and derusted the chassis, heat sinks and other various parts. It was a load of work! But it cleaned up pretty good.

All new amp driver boards that had to be stuffed by hand. Crazy! New speaker binding posts and RCA jacks as well. It looks so much better now though:

Sorry - forgot to snap a picture of it all put together. But here's an internet one:

- The bias does not adjust high enough.

- The bias does not adjust low enough.

- The meter is not working.

Unfortunately, there is no DIY fix for this. The RAM285 has extremely unfriendly serviceability. The PCB hides most components and is multilayered. Reworking the circuit board requires technical experience and proper tools. Moreover, the trouble has common causes but it may also be related to other less common troubles, so the amplifier should be fully tested to verify what the real trouble is.

Please inquire with us to get your RAM285 serviced if it is experiencing any trouble. 

Solution: Full restoration!

The main reservoir capacitors on the 5ch and 7ch models have reached their end of their usable life. They will boil, and vent - possibly causing permanent damage to surrounding circuit boards. Electrolytic fluids are corrosive. Furthermore, if these large main capacitors fail, they can damage the power supply by shorting to ground on one side, in a normally balanced supply. In most cases, the main fuse will blow from the failing capacitor, but there is no guarantee.

Solution: Full restoration!

The regulator circuits need to be rebuilt and modified to prevent future burning. Without service, these amps can be become UNUSUABLE.

Or this can happen:

We will also be introducing a new product called the 'Vintage Control Center' which is a power sequencer, surge protector, conditioner, and a general integrator of your vintage rack to make it work more seamless with newer technology. At the touch of your smartphone screen, you will even be able to control the volume of source units or preamps that otherwise do not have this feature.

I have toyed with the idea of including an inverter to a power amp input channel which would allow some amps to be used as common ground and others to be used in bridge mode.

https://www.facebook.com/share/p/15a2dWdYRh/

Some cool pictures of Greg with Bob Carver on a recent visit.  Would love a pair of those amps!!

Woohoo!

I am currently working on a relatively universal upgrade for Sunfire AMPs. The upgrade will include updates to the amplifier circuits and tracking down converter for more power, better durability and much better soundstage.

This is great news! I'm going to stress test these new transistors to make sure they meet the intended quality. If so, we'll be able to continue the M-500t mkII for years to come!

First of all - what's the bother of making something already expensive a little 'cheaper'? These large can caps are already demoted to 'on demand' manufacture and I don't think anyone will care if they spend $59.99 a piece or $69.99 a piece to fix something that needs it...and I would bet they'd pay an extra $10, or more, to get the same freaking size they were made in the first place!

Then there are the voltages...It's just as easy to find a 22,000uF 25V capacitor as it is to find a 10,000uF 450V capacitor.

But exceedingly rare to find a 6,800uF or 10,000uF 125V capacitor.

Weird?

So much money lost, really, because these new parts cannot fit in old stereo gear anymore. Not even not so old equipment! The ways around the size issue don't involve buying any other kinds of screw terminal capacitors, so the void is nothing more than a complete loss of money and waste of resources on parts that frankly, can't be used.

It would make sense to make parts that can be used over a wide range of applications...like...make them the same size they were made for decades before. Millions of applications.

But, they don't want that market. Instead, only a small niche market that doesn't need more than 'on demand' manufacturing.

OLD vs NEW

These don't fit in the same space!!!!!