| KevinLee |
Hello,
In the pre-amp section of my integrated amplifier there are (2) 17k8 resistors which are the feedback resistors. 1 for each channel.
I cannot find a good quality 17.8k resistor. What will happen if I change this value slightly?.
I was thinking of 18k.
Is it a worthwhile cause to upgrade this resistor to a caddock or vishay?
Any input or experiences would be appreciated.
Thanks
KevinLee:) |
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| mFinalHeaven |
| I am not sure about the circuit you are using, but usually such a small difference is minimal. |
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| analog_sa |
| Nothing much will happen. For peace of mind you should check the resistors which tie the - input to ground in order to calculate the gain but the change will likely be minute. Resistor sound is very much a personal choice and you should buy a few different makes and experiment in order to take the right decision. |
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| peranders |
| quote: | Originally posted by KevinLee
Hello,
In the pre-amp section of my integrated amplifier there are (2) 17k8 resistors which are the feedback resistors. 1 for each channel.
I cannot find a good quality 17.8k resistor. What will happen if I change this value slightly?.
I was thinking of 18k.
Is it a worthwhile cause to upgrade this resistor to a caddock or vishay?
Any input or experiences would be appreciated.
Thanks
KevinLee:) |
The difference between 18k and 17k8 is 0.09705 dB approx. = not very much
Vishay makes good and normal industrial quality resistors, work good in most cases.
What type or brand did you have now? |
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| KevinLee |
Peranders,
Right now there is only the stock metal film in place.
The feedback resistor is tied to ground with a 1K metal film.
Should I also upgrade the 1K resistor?
Thanks
KevinLee:) |
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| peranders |
| quote: | Originally posted by KevinLee
Peranders,
Right now there is only the stock metal film in place.
The feedback resistor is tied to ground with a 1K metal film.
Should I also upgrade the 1K resistor?
Thanks
KevinLee:) |
Seriously I don't think it's worthwhile only to change two resistors. I think the active elements (opamps?) are far more important. |
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| KevinLee |
Hello,
What are peoples favorite resistors for this application?
Caddock MK132, Tantalum, Vishay Bulk metal Foil, Draloric SMA-0207, Vishay CMF Type RN, are all types I am considering.
Any preferences of the above types for feedback circuits?
Thanks
KevinLee
PS. I am using OPA627 as my opeamp. |
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| analog_sa |
| quote: | | Should I also upgrade the 1K resistor? |
You should although IME the fb resistor has the strongest sonic influence
Only your own ears matter in selecting the resistor types
Btw 627 is seriously overrated sonically |
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| KevinLee |
analog_sa,
I have just installed the OPA627 via Brown Dog adapters and am letting it break in now. You are right that I might not like it. I previously had a AD826.
What is your choice for op-amp in pre-amp stage?
Thanks
Kevin |
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| peranders |
| quote: | Originally posted by analog_sa
Btw 627 is seriously overrated sonically |
Maybe so, but still excellent! :nod: |
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| Nuuk |
| FYI, The Welwyn RC55's which are very good resistors are available in the 17K8 value. (Farnell order code 340-376) |
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