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Hi i'm modding the sm pro audio ev84 ( 8 chnl preamp), and i took out the 4580 ic's and replaced them with 5532dd, but there was no change in sound...anybody knows any better substitutes with the same pin configuration for the 4580/5532?

thanks!

the NE5532 is quite useable, but there's only so much to gain by just exchanging a single device.
Usually with (pre)amps the greater share of issues is found in the whole (PCB) layout and spacing, and tolerance of all used parts. In some cases of bad design you may be lucky and get much better performance by just exchanging one or two resitors, but that's not too often anymore, in the days of CAD and SPICE. The latter one might even help you find a set of improvements, if you virtually re-build the whole circuit. But it is for you to decide wether it will be really worth the effort in the end. A Fiat will never become a 70ies Caddy...

LM4562 its one of the very best duals there is. if that doesnt make it sound better there might be some other things to try such as making sure there are no electrolytic input or output capacitors (replace them with metal film ones) make sure there is a power supply bypass capacitor near every chip. make sure the power supply itself is decent..

but you cant make chicken salad out of chicken 5h1t!

JoeKa wrote: A Fiat will never become a 70ies Caddy...

and thats a bad thing?

JoeKa wrote:the NE5532 is quite useable, but there's only so much to gain by just exchanging a single device...

absolutely - you'll even find them in fairly expensive (and well regarded) consoles
from price/performance it may even be the best line driver available
but at the very first input stage there are better solutions (imho)

my guess is only by aural experience, not by knowledge about circuit design - I have a Yamaha Bass Pre and I had a Radial Bassbone - the latter with a tiny bit more pleasing tone, but otherwise almost indistinguishable.
Both are based on those standard Opamps, as is my Korg Pandora.
All units deliver a solid sound, but not the definition and transparency you'd like for a recording.

I'm also not a fan of the plugin chip replacement like it's usually proclaimed in hifi circles, as the general circuit design and passive components are ignored completely.

cheers, Tom

I use the ultimate bass pre-amp:

http://www.tech21nyc.com/rpm.html

well, why not risk a peek inside ?
I bet you won't find anything but TL072/74 and NRC4558 inside ...

cheers, Tom

that TL072 was state of the art for some time....

The Technology

In 1989, B. Andrew Barta made his invention commercially available to players and studios around the world. SansAmp pioneered Tube Amplifier Emulation in professional applications for recording direct and performing live, and created an entirely new category of signal processing.

Over 10 years of research and development went into Tech 21's proprietary F.E.T. hybrid-based circuitry. Designed in the true tradition of tube amplifiers in their totality, SansAmp's 100% analog circuitry has a pre-amp stage and an output stage. It incorporates the harmonics and sweet overdrive characteristics uniquely inherent to tube amplifiers, which is largely caused by what is referred to as "push-pull" symmetrical clipping. While it is a common misconception, a single tube is physically incapable of producing this result. This is a feat that would normally require at least two tubes. Even at low volume, SansAmp captures the warm, rich, natural tones of a large variety of tube amplifiers, and does so without altering your instrument's individual personality.

Built-in speaker simulation is an integral part of the SansAmp Tube Amplifier Emulation circuitry. It is specifically engineered to yield a smooth, even response as would be achieved by a multiple-miked cabinet - without the peaks, valleys, and notches associated with single miking. Rather than interfere, the speaker simulation will actually complement the sound of your own speaker cabinets.

Another aspect of the technological advancement of SansAmp is that each model has a Universal Output (or output section). This feature allows SansAmp to be physically compatible with any application, so it can be used with full range (multi-track recorders, studio monitors, P.A. systems) as well as limited range systems (guitar or bass speaker cabinets).

From a vanload to a warehouse-full, SansAmp gives you the most coveted tube amp sounds and the ability to explore, refine and redefine your own. Each model responds to and interacts with the dynamics of your individual playing style, your individual musical style, and your instrument's individual tonality.

Discover for yourself why SansAmp has earned its reputation as being the best in the industry.

whats sansamp got to do with changing your op-amps?

The only preamp modding here was looking for better sounding 12AX7.

As the curious guy I am I just had a peek inside my Art TCS. It hosts NE5532 and TL072.

I also had a look at some data sheets: the 4580 has very low THD (compared with the 4560 at least) and this is one of the things bringing transparency IMHO.

Transparency is quite always a good thing, but for electric guitars and basses.
A too defined sound tends to enhance frets noise, fingers sliding on strings, pick noise, especially when compressed... (and heavy distortion is kind of compression)

If your going to replace OPAMPs only and not modding the whole circuit, maybe i guess you should look for chips with similar gain....

braincell wrote: While it is a common misconception, a single tube is physically incapable of producing this result. This is a feat that would normally require at least two tubes.

A single tube (used for two channel) clips mostly the upper or the lower side of the waveform
(enhancing mostly the 3rd harmonic instead of the 5th, as result, if I well remember..)
Even this enrich the sound... or not?

So you DON'T tube braincell...

Nowhere did I ever write anything about single tubes. Don't make up fake quotes for me.

isnt this thread called "better preamp ic than 4580/5532?"
for some reason it looks like people are talking about tubes and tube emulation. whats going on?

btw, the copy and paste of the sansamp blurb contains that quote about single tubes.

braincell wrote:The Technology

In 1989, B. Andrew Barta made his invention commercially available to players and studios around the world. SansAmp pioneered Tube Amplifier Emulation in professional applications for recording direct and performing live, and created an entirely new category of signal processing.

Over 10 years of research and development went into Tech 21's proprietary F.E.T. hybrid-based circuitry. Designed in the true tradition of tube amplifiers in their totality, SansAmp's 100% analog circuitry has a pre-amp stage and an output stage. It incorporates the harmonics and sweet overdrive characteristics uniquely inherent to tube amplifiers, which is largely caused by what is referred to as "push-pull" symmetrical clipping. While it is a common misconception, a single tube is physically incapable of producing this result. This is a feat that would normally require at least two tubes. Even at low volume, SansAmp captures the warm, rich, natural tones of a large variety of tube amplifiers, and does so without altering your instrument's individual personality.

Built-in speaker simulation is an integral part of the SansAmp Tube Amplifier Emulation circuitry. It is specifically engineered to yield a smooth, even response as would be achieved by a multiple-miked cabinet - without the peaks, valleys, and notches associated with single miking. Rather than interfere, the speaker simulation will actually complement the sound of your own speaker cabinets.

Another aspect of the technological advancement of SansAmp is that each model has a Universal Output (or output section). This feature allows SansAmp to be physically compatible with any application, so it can be used with full range (multi-track recorders, studio monitors, P.A. systems) as well as limited range systems (guitar or bass speaker cabinets).
.

well that quote was basic sales bullocks.

it exhibits the alarming habits of admen who distort facts and just make stuff up in order to sell things. wow, is it reall all analog?[sarcasm ]

so the circuit is a class B or AB circuit, no innovation there. one tube or output device is called class A, which is generally thought to be the best sounding. class A definitely exhibits the best linearity. in class A one device handles top and bottom of the waveform. in class B and AB, one device has the top(push) and the other the bottom(pull). this is more efficient(louder with less power required), but not as "musical" sounding.

the tech21 devices work very well indeed, but they are still medium quality consumer electronics. there's nothing special involved, no special circuits. if you like the sound, however, that's all that matters...

braincell wrote:Nowhere did I ever write anything about single tubes. Don't make up fake quotes for me.

I quoted part of a post from you. Reading it one more time I can guess the contents is reported from anywhere, but it didn't stand out to me at first read.

Hope my (silly indeed) joke about 'don't YOUTUBE?' didn't annoyed you...

@ Neutron: there's also valve stage preamps. It's not entirely OT... looks like tubes clips fairly, giving then anyway more headroom...
(:lol: sorry, since we're analogue talking, I wasn't able to wait for a valve preamp thread )

@ garyb: so the waveform from my single tube dual channel preamp (not the Art compressor; I didn't yet tested its output, I'm talking about a Presonus) ain't from B or AB and neither A class stage design....?
Is it half of a B or AB circuit?

garyb wrote:in class A one device handles top and bottom of the waveform. in class B and AB, one device has the top(push) and the other the bottom(pull). this is more efficient(louder with less power required), but not as "musical" sounding.

Gary, this is wrong. What you are describing is single ended or unballanced design versus push/pull or ballanced design.

Class A is about consuming full power all the time. You can say, that the PSU feeds the cirquit with full power all the time, where as in the other designs, the cirquit has to draw the needed amount of power out of the PSU.