JRC4558D Chips

[Echorec]

I put one of the Tubescreamer ICs up on Ebay if anyone is interested. Ciao everybody

(edit)

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=50912&item=3812913220

I was told they were long discontinued and quite desirable.

[petemoore]

..... :?   ..... :wink: ...... :?

[jimbob]

I dont get it? Are you saying your auctioning off the same ics we buy at smallbear or mouser ect.. for like 40-45 cents on e-bay?

[george]

hey echorec it might be an idea to put the link to your ebay item in your post ....

[Phorhas]

About that chip...

I experimented a bit with it in my quite modified TS and I find that the TI RC4558 IC is well... better (and so are afew others - but the TI RC4558 has that 4558 vibe, which I didn't find in the LF353 or TL082...)

May be I didn't experiment eanough but I find the JRC4558 a bit disapointing...

[jimbob]

i liked the rc4558 better as well..

[RDV]

I've got one of those "old" ones & a bunch of new ones & I dare anyone to tell the difference. I just don't get it. I put a Burr-Brown in my Boss SD-1 instead cause then I could tell a difference. It then sounded better.

RDV

[Phorhas]

I caould tell the difference between the stock TA75558 ans ANYTHING...

:lol:
LOL

[petemoore]

I sat right here and requested some from TI.
 What was so nicer about these chips [besides their percieved superiority to what I'd been using [TL082]...
 They sent THEM to ME,...FREE...very high quality service...and the chips themselves??? My Opinion
 Order a sample from TI and try 'em out.
 When that order came in 3 days after sitting on my     , and requesting them, my Opamp builds all miraculously became percieved as much more desirable.
 I go as far as: "The TI 4558's breathed new life into the OA builds, soon they were regularly seen on my pedal board with other improvements for the first time."
 I think an image of the chip, with a portion of fingerprint superimposed on it, and signed, blown up to 4'' length, would make an excellent poster !!!

[jazzyfingers04]

where exactly would I contact TI for this steal !?!

[StephenGiles]

Emperor's new clothes?

[Phorhas]

I see where you are getting at...

Well, I guess it comes down to suiting the best OA for a specific job, and play it to the right ear...

[Transmogrifox]

Emperor's new clothes?

:wink:

I must add that changing IC's does make a difference, but to get beyond subtle differences that may occur between different 4558 types, I would have to agree with the Emporer's New Clothes persuasion.

There is a more than subtle difference between say, a LM358 and an OP275 in a TS-9.  Even the TL082 sounds somewhat different than a 4558.  However, my most noticeable mods have come out of pre and post clipping stage filtering as well as introducing assymetrical clipping.  Changing IC's just makes me feel good about my sound.

[RedHouse]

So Pete, can you tell me how to order "samples" from TI?

I'd like to try some too.

[Mike Nichting]

Transmogrifox, would you care to share any of your TS mods with us??

I am very interested in the pre and post filtering etc.

Just curious bro ;-)

Mike Nichting

[george]

just to confuse everybody even more ...

check this out http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&category=22669&item=3720182408&rd=1&ssPageName=WDVW

A TS-808 with "even rarer Texas Instruments TL4558P chip" ...

maybe I can get a free sample of the TL4558P from TI?  :lol: [/url]

[Fret Wire]

I always liked the NE5532 the best. Seems a little quieter. The RC4558 is also nice. The JRC's all sound the same to me, new or old.

Funny thing about testing mods, is that by the time you unplug the pedal, change components, and plug back in, your frame of reference is gone. Hard to tell if you are hearing anything different, unless the changes are drastic.

To avoid this, I have 6 TS-9's that I got pretty good deals on just to try some different mods and their effect's. Still, just chaining the pedals together seems to negate the changes, probably due to the impedance.

So, I use a BC Rich JMP-45 programable switcher to test up to 5 pedals at once. This way, I can switch right in the middle of playing, chords, notes, etc, with just one stomp. Since the other pedals are switched out, no problems with the buffers affecting each other. Avoids losing the frame of reference, hearing wise.

With sockets in the various cap and resistor positions, you can test mods progressively from one pedal to the next. This way you can hear each mod's individual effect, if any, and their sum total effect, if any.  Sounds like a lot of work and money, but it's part of the fun. Also, you can get 4 used DS-1's or SD-1's for under $100 easy.  And the only real way to know what works, is to do the mods, not read about them.

[Phorhas]

I especially hate it when you go to all of that trouble (unplugging the box, unscrew the board, change - or sometimes unsolder and resolder) just to get a poor result...
Just when you thought you had it all nailed on the paper!

At least we love doing that...over and over again... great tone and perfect tuning doesn't happen by itself.

[StephenGiles]

Good morning to y'all. I pontificate - at gig volume, there is probably little difference between any distortion to well worn ears. If you are listening through headphones so as not to disturb neighbours, wives or girlfriends then I suppose..........

[brett]

I always liked the NE5532 the best.

This cheap and available little beauty gets approval every time TS-9s and the relatives gets discussed.  Quite a lot (maybe half) of those that have done extensive testing like this chip.  The way I see it, the NE5532 not only gets approval, it gets it from the gurus.  

Re 4558s - Is there a place in the forum we could discuss/explain the myth of the JRC4558 on the beginners page, so new folk don't get conned/overexcited/etc.  In one sense, I guess Small Bear does this by selling them for a buck each.  Any other ideas?