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TS9 TI RC 4558 vs the JRC 4558 after TS9 to 808 mod

2/28/2000 10:49 PM
John S.
TS9 TI RC 4558 vs the JRC 4558 after TS9 to 808 mod
This was just my opinion on this ok.....I thought that the JRC 4558 chip sounded better,but it allows for more hiss overall,especially at louder volume settings and the drive up all the way. My findings.....TS9 chips (2) (4558's)The JRC 4558 and a TI RC 4558 chip....  
Tonal thoughts. Strat through a 73 50 watt Marshall head(set for a clean tone) and a Marshall 4x12 slant cab w/Vintage 30's......Tone @ 9 o,clock,Volume @ 9 and drive all the way up........TS9 to 808 mod completed also.....  
..I didn't use the original TA 75558 chip for my listening tests.....But.........  
Between the TI RC 4558 and the JRC 4558.....Here's what my thoughts were.......  
The JRC 4558 is noisier.....Like the difference maybe between metal film and carbon comp resistors in that this chip allows for more hiss.....more noticible at higher volumes.....As long as the volume is at or less than 1/2 way up this isn't too much of a problem......Like the hiss of a cranking  
The JRC 4558 chip seems to allow for more sustain and I think this chip makes the pedal seem a bit louder and maybe a bit more compressed along with that........  
At the same settings of the guitar,amp,and the pedal......I was getting string feedback that I wasn't getting with the other 4558 chip.........I was in the same spot while doing this and playing the same riffs..........  
There isn't a huge difference in the tone between these 2 chips,but I did notice a difference.....The old chip is also a bit noisier.......The RC 4558 might be a bit high endier and the distortion isn't quite as smooth,but this is really close here......The RC 4558 chip is probably a better and more stable chip than the cheapo JRC 4558.....Who cares,I have tons of the RC 4558 chips now My 2 cents on this 4558 thing......John S.  

pHiLtHy John,I did some lis... -- 2/28/2000 11:48 PM