I have 2 different types of the old Radio Shack phono pre amps. I will post the pics and info on them later when I can get to them
I’d like to know if it’s worth it to open them up and do any updates or replacements of any of the components inside them. Yes I know they are old. Very old, from the late 70’s or early 80’s.
I know I’m not posting this properly without the models and photos. They will be posted in a few hours. I’ll try to open them up so we can see what’s inside them as well
If I have this posted in the wrong place. Please let me know and I’ll move this post or a moderator could do this for me
Thanks people and be safe
I’d like to know if it’s worth it to open them up and do any updates or replacements of any of the components inside them. Yes I know they are old. Very old, from the late 70’s or early 80’s.
I know I’m not posting this properly without the models and photos. They will be posted in a few hours. I’ll try to open them up so we can see what’s inside them as well
If I have this posted in the wrong place. Please let me know and I’ll move this post or a moderator could do this for me
Thanks people and be safe
There will be several electrolytic capacitors inside each that should be replaced with similar new ones
from a reliable distributor, perhaps of a different brand as well.
from a reliable distributor, perhaps of a different brand as well.
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The real “gotcha” with old RS equipment is that it was “economy-on-top-of-economy” designed. Basically Radio Shack, perpetually flirting with profitlessness, tended to demand her originally Japanese, then Taiwanese, and eventually Korean and Chinese suppliers to keep cutting the wholesale cost of buying her 'product mix'. The net result is that every last enterprising cost-cutter would substituted any part that might possibly save a penny, regardless of its sonic quality.
Thus, it wouldn't surprise me in the least that the photo of the innards shows a forest of light brown or dirty-red colored so-called 'ceramic' disk capacitors. And “furry” resistors, with off-color bands.
They worked.
Enough.
For high-school kids and impoverished middle-American adults to buy, make work.
After all, it really wasn't about “sonic quality”, but rather “louder must be better!”
A little (or lot) of distortion hardly mattered.
It wasn't Bach or Rachmaninoff being sent to Klipsch speaker stacks.
It was AC/DC … Queen … Beetles … Deep Purple, on volume “11”.
To breaking-up paper cone speakers in almost-paper fiberboard enclosures.
Know what I mean?
Just saying.
You might be braying after a setting moon.
⋅-=≡ GoatGuy ✓ ≡=-⋅
Thus, it wouldn't surprise me in the least that the photo of the innards shows a forest of light brown or dirty-red colored so-called 'ceramic' disk capacitors. And “furry” resistors, with off-color bands.
They worked.
Enough.
For high-school kids and impoverished middle-American adults to buy, make work.
After all, it really wasn't about “sonic quality”, but rather “louder must be better!”
A little (or lot) of distortion hardly mattered.
It wasn't Bach or Rachmaninoff being sent to Klipsch speaker stacks.
It was AC/DC … Queen … Beetles … Deep Purple, on volume “11”.
To breaking-up paper cone speakers in almost-paper fiberboard enclosures.
Know what I mean?
Just saying.
You might be braying after a setting moon.
⋅-=≡ GoatGuy ✓ ≡=-⋅
Even the HK Citation I tube preamp had a Z5U ceramic input coupling capacitor for the phono stage.
Really bad, and shorting it out definitely improved the sound. If the RS preamps have such capacitors,
get rid of them.
Really bad, and shorting it out definitely improved the sound. If the RS preamps have such capacitors,
get rid of them.
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The little black tanks?? Trash!!
The supply voltage is only 15V. So even with low gain, hot pressings will distort. The caps were 20% maybe. The <500Hz response was lamed by lack of open-loop gain. This may be good, because with the transformer inside the box 60Hz hum would be awful. And as said, low-low-low-low bidder. The last time I heard real excess hiss in a transistor was one of these boxes.
You can do so very much better, for cheap, that it isn't funny.
The supply voltage is only 15V. So even with low gain, hot pressings will distort. The caps were 20% maybe. The <500Hz response was lamed by lack of open-loop gain. This may be good, because with the transformer inside the box 60Hz hum would be awful. And as said, low-low-low-low bidder. The last time I heard real excess hiss in a transistor was one of these boxes.
You can do so very much better, for cheap, that it isn't funny.