Looking before I leap. As a newb, I'm wondering if I can switch the op amps on my Music Hall 25.2 CD player. The original op amps are four Burr-Brown OPA-2604's. I'm thinking it might be good to replace them with four National Semiconductor LM4562NA/NOPB DUAL HI PERF,HI FI (from Mouser).
Is this okay to do? Just pull the old ones and put in the new.
I think this is the case. I believe this op amp has been used to replace the stock op amps in the 25.2 CD player as I describe here. Not knowing the specs of the op amps involved, I'm going on what I've read regarding modding this cd player.
Is this okay to do? Just pull the old ones and put in the new.
I think this is the case. I believe this op amp has been used to replace the stock op amps in the 25.2 CD player as I describe here. Not knowing the specs of the op amps involved, I'm going on what I've read regarding modding this cd player.
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Thanks DUG!
See, I was afraid this would happen. Right off the bat I'm in over my head. I don't know how to check the supply. I don't have the tools to check the supply. I don't know where to find information about the supply. I'll google around a bit now, tho.
From what you say, the 25.2's supply may be too great or too small for the LM, is that right?
See, I was afraid this would happen. Right off the bat I'm in over my head. I don't know how to check the supply. I don't have the tools to check the supply. I don't know where to find information about the supply. I'll google around a bit now, tho.
From what you say, the 25.2's supply may be too great or too small for the LM, is that right?
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Off topic, but I am astounded when I see the flags of the various countries represented here. I want to thank every one of you.
So far, I've installed Vishay MKP1837's to bypass the output coupling(?) caps, removed the RCA wire connectors soldered to the board and the stock wire. I soldered directly to the board Ohno single crystal copper wire to connect to the RCA jacks. Just these things made a very noticeable improvement.
Something I can pass on that might be helpful is the use of Vishay MKP1837 as bypass caps. It's a tip I picked up at The Lab on the AudioCircle site. I can point you directly to the thread if anyone is interested.
Now I am planning to pick up another multimeter. Any suggestions for a good multimeter when low price is important? I have a Radio Shack nearby.
So far, I've installed Vishay MKP1837's to bypass the output coupling(?) caps, removed the RCA wire connectors soldered to the board and the stock wire. I soldered directly to the board Ohno single crystal copper wire to connect to the RCA jacks. Just these things made a very noticeable improvement.
Something I can pass on that might be helpful is the use of Vishay MKP1837 as bypass caps. It's a tip I picked up at The Lab on the AudioCircle site. I can point you directly to the thread if anyone is interested.
Now I am planning to pick up another multimeter. Any suggestions for a good multimeter when low price is important? I have a Radio Shack nearby.
One man's simplicity is another man's incomprehensible complexity.qusp said:
Maxwell's equations look a lot simpler (to a high energy physicist) when written in relativistic 4-space notation, as the artificial distinction between electricity and magnetism disappears, but I doubt if many EEs would see them as simpler. Fourier theory is a simple application of inner product spaces.
Similarly, an experience DIYer might see passive I/V as simpler than an opamp virtual ground circuit for terminating a DAC, but someone who just wants to swap an opamp might find the reworking rather daunting. Also, many passive I/V circuits push the DAC well outside its written spec in terms of output voltage so are likely to introduce distortion - it might even be this distortion which some people like! Don't make things too simple, as 'too simple' does not work.
DF96,
I run into the same simplicity/complexity issues in my field. I have a PhD in a scientific field, but it is completely unrelated to electronics. I find that when say something that is commonplace in my field, people outside the field get a blank look. Then, when I try to explain why it's simple, they get completely lost. I think I'm making it simple, but they are completely in the woods.
People within fields have mental habits and conceptual connections that are not shared outside the field. It becomes frustrating to both parties when the information and benefits of understanding cannot be readily communicated. Or, to make it simple, "One man's simplicity is another man's incomprehensible complexity."
I always start my electronics posts with a statement of ignorance so those within the field can avoid the impending frustration if they so desire. I try to give fair warning of my ignorance so I very much appreciate anyone who is generous enough to try to help.
The op amps I am planning to install are fairly inexpensive. Would it hurt anything other than the op amps, if I just installed them and applied power? If they burn out, I don't care. I just don't want them to take anything else with them if they do burn out. Is that a reasonable course?
I suppose if they are underpowered, they will just not sound good, but do no damage to the cd player.
Anyone have thoughts on that?
I'll be glad to report my results.
I run into the same simplicity/complexity issues in my field. I have a PhD in a scientific field, but it is completely unrelated to electronics. I find that when say something that is commonplace in my field, people outside the field get a blank look. Then, when I try to explain why it's simple, they get completely lost. I think I'm making it simple, but they are completely in the woods.
People within fields have mental habits and conceptual connections that are not shared outside the field. It becomes frustrating to both parties when the information and benefits of understanding cannot be readily communicated. Or, to make it simple, "One man's simplicity is another man's incomprehensible complexity."
I always start my electronics posts with a statement of ignorance so those within the field can avoid the impending frustration if they so desire. I try to give fair warning of my ignorance so I very much appreciate anyone who is generous enough to try to help.
The op amps I am planning to install are fairly inexpensive. Would it hurt anything other than the op amps, if I just installed them and applied power? If they burn out, I don't care. I just don't want them to take anything else with them if they do burn out. Is that a reasonable course?
I suppose if they are underpowered, they will just not sound good, but do no damage to the cd player.
Anyone have thoughts on that?
I'll be glad to report my results.
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Worst case could be an ultrasonic oscillation which might damage a power amplifier. Some people on here know what they are doing wth opamp swaps, so follow their advice. Others just think they know what they are doing; unfortunately I am not in a position to always tell who is who! Ask questions and query what people say: the first group will answer your questions while the second group will just bluster.
I've seen some CD players with fusible resistors in the power rails - its possible that an over-voltaged opamp might go short and fuse the resistors. Resistors are much cheaper than chips, its just the inconvenience of fault finding. OTOH I've not seen a CD player that uses 18V or above rails for the analog stage, so its probably worth taking the risk of just plugging and playing.
Update and correction
Update: The National Semiconductor LM4562NA/NOPB DUAL HI PERF,HI FI op amps are not suitable to swap for the stock Burr Brown 2604's in a Music Hall 25.2. The NS op amps sound superior to the stock BB op amps until deep bass is encountered, then they distort terribly. I suppose this may be related to the differing operating specs for the different op amps.
Correction: In my original post, I misstated the stock op amps as Burr-Brown OPA-627s. The stock op amps are Burr Brown 2604's.
Update: The National Semiconductor LM4562NA/NOPB DUAL HI PERF,HI FI op amps are not suitable to swap for the stock Burr Brown 2604's in a Music Hall 25.2. The NS op amps sound superior to the stock BB op amps until deep bass is encountered, then they distort terribly. I suppose this may be related to the differing operating specs for the different op amps.
Correction: In my original post, I misstated the stock op amps as Burr-Brown OPA-627s. The stock op amps are Burr Brown 2604's.
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