I have a question for Crown amp gurus. I recently acquired a used Crown D-75 amp. One thing kind of bothers me and it's not the sound quality. The "on" indicator light some times stays on, some times not and other times it flickers. Is this a case of bad bulb (small problem) or could this be a problem with the power supply (bigger problem)? If it's former, the replacing of bulb looks difficult - a bowed sheet metal which holds the bulb mounting bracket, is clipped in there and it won't move when I tried to with my fingers. Do I need a special tool?
Thank you in advance.
Thank you in advance.
Bad switch perhaps? My old Peavey CS800 does the *opposite*, sometimes the bulb goes out for no reason...replacing the bulb means replacing the switch in my case. Consider yourself lucky you can change the bulb at all.
The shroud may move when turned with pliers....make sure its not screwed in somehow. If possible, add an LED as the replacement.
The shroud may move when turned with pliers....make sure its not screwed in somehow. If possible, add an LED as the replacement.
I have found this:
crown D-75???????????????????? - ????????????????
(http_blog.goo.ne.jp_yutaka_022/e/49cc8eaead14a77f50ee34a7a6b243fa)
Google Übersetzer
Vintage Crown D-75 D75 Power Amplifier ? Vintage Tube Amplifiers
D-75
D60
found by
http://www.eonet.ne.jp/~audio/amp4.htm (photos from a wide range of vintage amp devices)
D-75 datasheet about
http://www.crownaudio.com/pdf/legacy/k1076-7.pdf
but no PDF service manual from D-75 (and also not from D-60 and "SA 20-20") are to find by
Discontinued Amplifier Products
I have send an inquiry to get the appropriate navigation advives.
crown D-75???????????????????? - ????????????????
(http_blog.goo.ne.jp_yutaka_022/e/49cc8eaead14a77f50ee34a7a6b243fa)
Google Übersetzer
Vintage Crown D-75 D75 Power Amplifier ? Vintage Tube Amplifiers
D-75
D60
found by
http://www.eonet.ne.jp/~audio/amp4.htm (photos from a wide range of vintage amp devices)
D-75 datasheet about
http://www.crownaudio.com/pdf/legacy/k1076-7.pdf
but no PDF service manual from D-75 (and also not from D-60 and "SA 20-20") are to find by
Discontinued Amplifier Products
I have send an inquiry to get the appropriate navigation advives.
Attachments
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I pulled out the "on" indicator bulb (what a pain it was!). I must have shook it some way during the process that now it stays on.
What can I replace it with in the future? I'm not familiar with this particular bulb. I put multimeter across it while it's on and it reads 114 VAC (does not read DC). Any suggestions?
Also, I've read online that it is common for Crown D series to make "pop" sound from the speakers a few seconds after turning off. I have two of these amps and one does it very faintly while the other is fairly loud. Does this have to do with aging capacitor somewhere? If not, what else could it be? Thanks.
An externally hosted image should be here but it was not working when we last tested it.
What can I replace it with in the future? I'm not familiar with this particular bulb. I put multimeter across it while it's on and it reads 114 VAC (does not read DC). Any suggestions?
An externally hosted image should be here but it was not working when we last tested it.
Also, I've read online that it is common for Crown D series to make "pop" sound from the speakers a few seconds after turning off. I have two of these amps and one does it very faintly while the other is fairly loud. Does this have to do with aging capacitor somewhere? If not, what else could it be? Thanks.
basic informations about neon lights:
Neon lamp - Wikipedia, the free encyclopedia (english)
Glimmlampe ? Wikipedia (german)
have a look also there:
http://www.diyaudio.com/forums/anal...ized-neon-lamp-micro-seiki-5-where-order.html
Neon lamp - Wikipedia, the free encyclopedia (english)
Glimmlampe ? Wikipedia (german)
have a look also there:
http://www.diyaudio.com/forums/anal...ized-neon-lamp-micro-seiki-5-where-order.html
From Crown...
www.crownaudio.com.
They're very generous about their technical info.
What I'd do is update your amp to an LED. Find the 15V supply and install a green LED and appropriate dropping resistor.
www.crownaudio.com.
They're very generous about their technical info.
What I'd do is update your amp to an LED. Find the 15V supply and install a green LED and appropriate dropping resistor.
only technical short form info (specifications) I found by D75:
http://www.crownaudio.com/pdf/legacy/k1076-7.pdf
but no schematic.
The SA2020 is not listed about
http://www.crownaudio.com/gen_htm/legacy/legacamp.htm and
http://www.crownaudio.com/amp_htm/ampinfo.htm
but perhaps anywhere else (please let me know, if you find it).
Only this I have found (go to Page 11, Mr. Gerald Stanley) concerning the Crown's first SS amp "SA 20-20":
http://www.crownaudio.com/amp_htm/ma-anniv/140623.pdf
from the D60 all informations include schematics online in the meantime:
http://www.crownaudio.com/pdf/legacy/d60-im.pdf
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There is some early stuff not on their website. Email David Glass (DGlass@crownintl.com) if you can't find it. Also ask for any subsequent tech notes for the equipment you're working on. Often the tech notes will address the problem you're having. Normally you have to be a service center to get to the tech notes online.
Note: David is not a heavy duty technical guy but is more of a customer service engineer.
Note: David is not a heavy duty technical guy but is more of a customer service engineer.
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