Crown Macro Reference Monster amp rework.

[Bob Boyer]

Sounds cool!

Yeah, I'd be looking for another if the distortion is as low as the wattage is high...

Crown generally made "tools" not "toys" so, maybe a bit more noise than a "fancy" amp, but serious horsepower to deafen a stadium.

We use these for house amps in the Fine Arts Center. A rack full of them upstairs in the catwalks. Excellent amps with serious longevity. We've used Crowns since the facility was built in 1979. First the DC-300s, then these. Had one walk off during the renovation. Facilities tried to make us buy the replacement but lost that fight.

@ Perry - that amp's exterior condition is pretty nice. A little spray to cover the scratches on the cover sheetmetal and it will look good in that system. Nice find!

 

[Gepetto]

Is this a bridge output? The heatsinks look like the MA10,000

Yes Don, H bridge output configuration.

 

[WOPL Sniffer]

We use these for house amps in the Fine Arts Center. A rack full of them upstairs in the catwalks. Excellent amps with serious longevity. We've used Crowns since the facility was built in 1979. First the DC-300s, then these. Had one walk off during the renovation. Facilities tried to make us buy the replacement but lost that fight.

@ Perry - that amp's exterior condition is pretty nice. A little spray to cover the scratches on the cover sheetmetal and it will look good in that system. Nice find!

Yep, a little paint is in order. thanks

 

[El Magnifico]

Very cool. I hope to have mine up and running here in a couple days. One of the things I don't like about the PL is no way to run another set of speakers. This amp is WAY more versatile. What PIP do you have in the back??? I need to find another one of these if it sounds good, I'll call the electrician and get an aux circuit put in utilizing 2 30 amp outlets for the amps. Then I can up the power BIG TIME.

Hello Perry. I don't have any PIP card in it. Just as it came from the seller. I have a dedicated 30amp breaker for it. Just realized yesterday that the "Macro Reference" sign is off! Is that a lamp needed?

I have 7 Crown Amps here: D 150, DC 300 and the monster. Used to have more Crown stuff, like (2) open reel decks and the IC 150 pre, but slimmed down the collection years ago.

 

[WOPL Sniffer]

Hello Perry. I don't have any PIP card in it. Just as it came from the seller. I have a dedicated 30amp breaker for it. Just realized yesterday that the "Macro Reference" sign is off! Is that a lamp needed?

I have 7 Crown Amps here: D 150, DC 300 and the monster. Used to have more Crown stuff, like (2) open reel decks and the IC 150 pre, but slimmed down the collection years ago.

There is a switch in under the front panel that turns the lights on and off.

 

[WOPL Sniffer]

I got all the new transistors stabbed in. I just have some cables to plug in and get it ready for power. I want to double check everything so I'm not the "Talk of The Town". It's just about there. I'll have to check the weather to see if some touch up paint is in order.... Oh wait, no painting weather for a while DUH!!!

 

[WOPL Sniffer]

SWEET!!!!! She is NOT in protection anymore. That issue is cured. I haven't tested it yet since the front panel is not lighting up. It has a switch on it for turning the display on and off. It doesn't affect the operation of the amp but I do want to address that. It's got a 2 pin power plug to the power supply so that's where I'll start. I left off the front panel cover just in case. Time to check out the skizmo for the panel.

NO KABOOOOOOM today boys

 

[WOPL Sniffer]

Damn, figures, the Crown has 4 volumes of Service manual and none has a friggin skizmo. I'm throwing up the BULLSHIT FLAG! That's 2 amps in a row. WTF???

 

[WOPL Sniffer]

Hello Perry. I don't have any PIP card in it. Just as it came from the seller. I have a dedicated 30amp breaker for it. Just realized yesterday that the "Macro Reference" sign is off! Is that a lamp needed?

I have 7 Crown Amps here: D 150, DC 300 and the monster. Used to have more Crown stuff, like (2) open reel decks and the IC 150 pre, but slimmed down the collection years ago.

Did you find a schematic for the Macro Reference? I flipped the switch for the front panel lightening and it didn't come up. Kinda tough to troubleshoot without the schematic.

 

[WOPL Sniffer]

Yes Don, H bridge output configuration.

Can you touch on that a little Joe? I guess I don't get the verbiage.

 

[Gepetto]

Unlike what you are used to with Phase Linear amps where one side of the speaker is grounded and the other side swings plus and minus, H-bridge amps have both speaker terminals. When the red terminal is swinging positive, the negative speaker terminal is swinging equally opposite and negative. This behavior doubles the voltage swing that is applied to the speaker, thus increasing power output

 

[WOPL Sniffer]

Unlike what you are used to with Phase Linear amps where one side of the speaker is grounded and the other side swings plus and minus, H-bridge amps have both speaker terminals. When the red terminal is swinging positive, the negative speaker terminal is swinging equally opposite and negative. This behavior doubles the voltage swing that is applied to the speaker, thus increasing power output

Got it. Thank you.

 

[Gepetto]

Got it. Thank you.

It looks like an H. Can be configured in emitter follower mode as well which is what yours likely is...

 

[WOPL Sniffer]

I pulled out the violin and even that didn't help trying to get the schematic from Harmon (Crown Owners). I hate to have to shotgun anything but I want that front panel lit. I guess I'll tear it apart and start trying to figure it out. Shit!

 

[Gepetto]

Its not this Perry?

Crown Macro Reference Schematic - Bing images

 

[WOPL Sniffer]

Its not this Perry?

Crown Macro Reference Schematic - Bing images

I can't tell Joe. When I open it, it's unreadable.

 

[WOPL Sniffer]

Its not this Perry?

Crown Macro Reference Schematic - Bing images

I think that website that SAYS they have the schematic (Elektrotanya) is a Rusky site just waiting to screw ya.

 

[WOPL Sniffer]

Its not this Perry?

Crown Macro Reference Schematic - Bing images

I risked it Joe, and I was able to download the 3 pages of skizmo's and I don't think I caught the clap or anything. I can now troubleshoot that part of the circuit. It's pretty simple. I only see one part that will be an issue, the rest of them are easy. Thanks

 

[Gepetto]

I risked it Joe, and I was able to download the 3 pages of skizmo's and I don't think I caught the clap or anything. I can now troubleshoot that part of the circuit. It's pretty simple. I only see one part that will be an issue, the rest of them are easy. Thanks

I have an expendable computer for Russian downloads

 

[WOPL Sniffer]

This will be the only hold up for me if it's bad. I don't know what the hell it is and on the schematic, Crown calls it a Low Noise Power Supply but it's shown as a box with no components. It's got a red and a black wire coming in, and a white and a black wire coming out with + and - respectively. It drives the LED lights (the Crown Logo and Macro Reference Logo). You can see in the skizmo in the middle on the bottom it says EL Power Supply. I'll fire it up tomorrow and see if I have a DC voltage out of it to drive the LED panels. I put a picture of it on the next page.