Imix500: " ... My gut feeling would be in the neighborhood of 300-400VA each. "
There may be some way to approximately rate these by wire sizes and weight of each ... Wire size of course being mathimatically related to current carrying ability.
" Main transformers- each 60.5V " ... each meaning two main windings? Are these used in series to produce +60.5 VDC and -60.5 VDC ? ~~= +/- 60DC -0- 60DC
" Motorformer- 18-0-18 " ... is this also the DC voltage output through rectification?
If you can get a handle on overall current rating at the power cord, then the results would be more clear.
(4 amp fuse for 120 VAC ~~= approximately 250 VA, assuming standard engineering practice of derating the fuse by half. The factory lable on the back of each unit might say something like 250 watts = approximately 125% of "real" power rating of the transformer of about 200 VA or slightly less. ... or something like such.)
Incidently, a +/- 60 VDC rectified from this transformer makes them quite useful for DIY. see http://aussieamplifiers.com/nx150.htm ... uses +/- 63 VDC to power these very decent 150 Watt power MOSFET amps.
There may be some way to approximately rate these by wire sizes and weight of each ... Wire size of course being mathimatically related to current carrying ability.
" Main transformers- each 60.5V " ... each meaning two main windings? Are these used in series to produce +60.5 VDC and -60.5 VDC ? ~~= +/- 60DC -0- 60DC
" Motorformer- 18-0-18 " ... is this also the DC voltage output through rectification?
If you can get a handle on overall current rating at the power cord, then the results would be more clear.
(4 amp fuse for 120 VAC ~~= approximately 250 VA, assuming standard engineering practice of derating the fuse by half. The factory lable on the back of each unit might say something like 250 watts = approximately 125% of "real" power rating of the transformer of about 200 VA or slightly less. ... or something like such.)
Incidently, a +/- 60 VDC rectified from this transformer makes them quite useful for DIY. see http://aussieamplifiers.com/nx150.htm ... uses +/- 63 VDC to power these very decent 150 Watt power MOSFET amps.
Hi FastEddy, the amp has two seperate power transformers. one for each channel with one winding. After rectification + is tied to one output device heatsink - is tied to the other. Crown does thier grounded bridge thing after that (still working on wrapping my head around it).
The main transformers' secondary is 60.5v -I had about 86v at the filter cap.
Wire size on the secondaries is 16ga I think.
The Motorformers output is 18-0-18 Vac and is rectified to 24v for the protection relays then regulated to +/- 15v
Crown says at full loading (2 ohms/ch with 50% duty cycle pink noise) it draws 720W out of the wall.
The main transformers' secondary is 60.5v -I had about 86v at the filter cap.
Wire size on the secondaries is 16ga I think.
The Motorformers output is 18-0-18 Vac and is rectified to 24v for the protection relays then regulated to +/- 15v
Crown says at full loading (2 ohms/ch with 50% duty cycle pink noise) it draws 720W out of the wall.
" ... The main transformers' secondary is 60.5v[ac] -I had about 86v[dc] at the filter cap. ..."
My mistake ... too bad as secondary voltage may be too high for DIY usefulness, unless there is an easy way to "simulate" a ground (ala Crown methodology = +/- 43 VDC = +43DC - 0 - 43DC).
#16 awg wire is easily mistaken for 14 in a bundle, #16 awg is easily mistaken for #18 when bare (in a transformer, etc.)
" ... 18-0-18 Vac and is rectified to 24v[dc] ... " ... is of course very useful for things like pre-amps, etc.
" ... loaded ... 720W ..." !! ... then the transformer is probably 600 VA = total for all secondaries ... OR ... each transformer ~~= 300 VA ... thus the Crown designation of "M...T... 600".
Inventory status? ... got 'em out of the Crown cases? Still installed? ... How many in good condition? Shipping weight? Shipping weight for the whole Crown MT 600 unit? Is it possible to do something like this: http://3dotaudio.com/ampics.html ??
My mistake ... too bad as secondary voltage may be too high for DIY usefulness, unless there is an easy way to "simulate" a ground (ala Crown methodology = +/- 43 VDC = +43DC - 0 - 43DC).
#16 awg wire is easily mistaken for 14 in a bundle, #16 awg is easily mistaken for #18 when bare (in a transformer, etc.)
" ... 18-0-18 Vac and is rectified to 24v[dc] ... " ... is of course very useful for things like pre-amps, etc.
" ... loaded ... 720W ..." !! ... then the transformer is probably 600 VA = total for all secondaries ... OR ... each transformer ~~= 300 VA ... thus the Crown designation of "M...T... 600".
Inventory status? ... got 'em out of the Crown cases? Still installed? ... How many in good condition? Shipping weight? Shipping weight for the whole Crown MT 600 unit? Is it possible to do something like this: http://3dotaudio.com/ampics.html ??
An option might be -depending on the construction of the transformer- to unwind or bypass the secondary...
Or this amp would probably work well on the crown power supply:
http://www.marchandelec.com/ftp/mb401man.pdf
Not a bargain though....
Or this amp would probably work well on the crown power supply:
http://www.marchandelec.com/ftp/mb401man.pdf
Not a bargain though....
As far as inventory, most have been sold after investigating and the two we have left are pretty new with date codes of 1996.
I just took the liberty of cracking one open to measure- and clean out several ounces of dust.
I have found although a bunch of older amps, a urei, a ramsa, an AB systems, and a bunch of dc150s.
I just took the liberty of cracking one open to measure- and clean out several ounces of dust.
I have found although a bunch of older amps, a urei, a ramsa, an AB systems, and a bunch of dc150s.
Well guys, i hate to burst everyone's bubble. But i believe class D will be the best way for me to go with this project. Also with the transformerless power supply of coldamps.com it will just be an easy construct. These products will fit in to the shell with ease. The cooling process i'm still thinking about. The heat sinks on the crown amp get clogged with dust easily. So i was thinking about a way to keep the Class D's cool(i know about their high efficiency rate). I just want to make sure.
imix500: " ... and a bunch of dc150s. ..."
Cool, you must have quite a parts storage facility ... or do you have a barn full of junk?
dirtyk777: " ... But i believe class D will be the best way for me to go with this project. ..."
Oh, well ... good luck, I'm sure you won't be disappointed with the outcome. (Looks like the only thing you will be keeping of the old Crown is the power switch and the case.)
Cool, you must have quite a parts storage facility ... or do you have a barn full of junk?
dirtyk777: " ... But i believe class D will be the best way for me to go with this project. ..."
Oh, well ... good luck, I'm sure you won't be disappointed with the outcome. (Looks like the only thing you will be keeping of the old Crown is the power switch and the case.)
dirtyk777: " ... an automotive painter in a past life ..."
I have always felt that someone could make a handsome vocation out of a short run powder coating operation ... mostly for folks involved in DIY audio, auto, plane, boat, etc ... making small parts and needing to get 'em pretty.
Got any good ideas along this line?
I have always felt that someone could make a handsome vocation out of a short run powder coating operation ... mostly for folks involved in DIY audio, auto, plane, boat, etc ... making small parts and needing to get 'em pretty.
Got any good ideas along this line?
Powder coating is a little bit different method than incorporated with painting cars. Powder coating uses a charge to make little flakes of powdered paint stick to the object being painted. You could do this to the case, but definitely not the electronic parts inside.
Now the process its self, booth and prep, is very expensive. So their really is no such thing as a small time powder coating operation. That is why you see mass produced powder coated items, like after market car parts/boat parts/etc.
Now the process i know of automotive painting is very tedious but if done right, paint will be the most expensive item that needs to be purchased.(Supplies also kills this type of painting[sandpaper, razor blades, tape, degreaser,cut and buff materials]) But will not damage parts and still stand up to the heat of the amp(do not take my word for it, different paints act differently under heat and pressure, thus cheap paint aka krylon from home depot can not hold up). I will be using Sikkens auto motive paint supply. I'm still thinking about designs, but i will incorporate any company's logo if i use their parts just to show where the technology and design came from.
Email me if you want to know the full process of painting...make sure you put a subject because i get alot of junk mail.
Now the process its self, booth and prep, is very expensive. So their really is no such thing as a small time powder coating operation. That is why you see mass produced powder coated items, like after market car parts/boat parts/etc.
Now the process i know of automotive painting is very tedious but if done right, paint will be the most expensive item that needs to be purchased.(Supplies also kills this type of painting[sandpaper, razor blades, tape, degreaser,cut and buff materials]) But will not damage parts and still stand up to the heat of the amp(do not take my word for it, different paints act differently under heat and pressure, thus cheap paint aka krylon from home depot can not hold up). I will be using Sikkens auto motive paint supply. I'm still thinking about designs, but i will incorporate any company's logo if i use their parts just to show where the technology and design came from.
Email me if you want to know the full process of painting...make sure you put a subject because i get alot of junk mail.
" ... Powder coating uses a charge to make little flakes of powdered paint stick to the object being painted. ..."
I'm not talking about the whole electronic device getting painted as a unit, just sub assemblies and parts like old cases turned into pretty new ones, etc.
I believe that the power coating process is not nearly as complicated as might first appear. Doesn't it use an audio type DC output power supply?
I'm not talking about the whole electronic device getting painted as a unit, just sub assemblies and parts like old cases turned into pretty new ones, etc.
I believe that the power coating process is not nearly as complicated as might first appear. Doesn't it use an audio type DC output power supply?
http://www.finishing.com/Library/pennisi/powder.html
1. I don't have a large oven. Nor an oven for that matter.
2. Don't have random liquid metals i can dip parts in.
3. Don't have an electrostatic paint gun.
4. Dont have patience for powder coating(or for automotive painting for that matter so i have to take my ADD meds)
Etch on this site basically means sand down with metallic grinder.
1. I don't have a large oven. Nor an oven for that matter.
2. Don't have random liquid metals i can dip parts in.
3. Don't have an electrostatic paint gun.
4. Dont have patience for powder coating(or for automotive painting for that matter so i have to take my ADD meds)
Etch on this site basically means sand down with metallic grinder.
V-bro,
I'm not quite sure what you mean by won't stand up to rain/heat.
Powder coating, after the clear coat/sealer selection, is one of the strongest paint surface applications you can do to your project. It is very thick though...very very thick. So if you really wanted to do it, make sure you tape up any holes screws or anything to that matter will go in. Because after you painted over a hole with powder coating, you basically have to drill out another one which in itself will defeat the aesthetic look to your project....
This is why i believe good ole wet sanding, and primer, and automotive paint will do the trick that i'm looking for. And is far more than enough to withstand the heat dissappation of a Class D amp.
I'm not quite sure what you mean by won't stand up to rain/heat.
Powder coating, after the clear coat/sealer selection, is one of the strongest paint surface applications you can do to your project. It is very thick though...very very thick. So if you really wanted to do it, make sure you tape up any holes screws or anything to that matter will go in. Because after you painted over a hole with powder coating, you basically have to drill out another one which in itself will defeat the aesthetic look to your project....
This is why i believe good ole wet sanding, and primer, and automotive paint will do the trick that i'm looking for. And is far more than enough to withstand the heat dissappation of a Class D amp.
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