# THAT4301 Substitute?



## twebb6778 (Feb 14, 2021)

I'm currently building a Muzzle with SMD THAT4301, and plan to build more in the future. It's a wicked circuit!

That being said (no pun intended), the THAT4301, particularly in an SMD package, seems to getting harder to find and prices are starting to become silly. In Australia it'll cost close to $40 for a single IC.

With these being discontinued, is there a suitable pin for pin replacement available? Maybe the 4305? Failing that, is there something else I can frankenstein onto my builds?


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## EGRENIER (Mar 24, 2021)

Seems you never got an answer on this topic.  I have the same question.  According to what I can find the 4305 is the replacement, but I don't know enough (or understand enough) about IC to actually confirm if it would would in the Muzzle circuite.


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## Robert (Mar 24, 2021)

The 4305 isn't a _direct_ replacement for the 4301.    It'll involve a modified circuit or an adapter board with an additional opamp.

It's also a completely different package style with much smaller pins.


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## EGRENIER (Mar 24, 2021)

Thanks for the info, so we are in a jam, 4301 can't be replaced and seems almost impossible to procure from trusted source.

Anyone knows of trusted vendors that sill carry some ?


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## Robert (Mar 24, 2021)

Don't risk it with any unreliable sources, I'll work up an adapter board for the 4305.


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## zgrav (Mar 24, 2021)

Robert said:


> Don't risk it with any unreliable sources, I'll work up an adapter board for the 4305.


Maybe a modified Muzzle PCB using the 4305.....


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## twebb6778 (Mar 24, 2021)

I ended up rolling the dice and buying one from aliexpress that someone else on here mentioned having success with.

Hasn't arrived yet but I'll update once it comes. From memory the 4305 needs a few more external components (2 op amps I think?) but will do the job. An adapter board or new Muzzle to accommodate the 4305 would also be amazing, but I understand you're busy so no sweat.


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## zipfool (May 18, 2021)

twebb6778 said:


> I ended up rolling the dice and buying one from aliexpress that someone else on here mentioned having success with.
> 
> Hasn't arrived yet but I'll update once it comes. From memory the 4305 needs a few more external components (2 op amps I think?) but will do the job. An adapter board or new Muzzle to accommodate the 4305 would also be amazing, but I understand you're busy so no sweat.


Any update on this? I realize it might still be traveling halfway around the world to get to you, but I'm curious what you've found. Otherwise, PCBs like the Muzzle are a bit useless until there's a solution :-(


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## twebb6778 (May 18, 2021)

zipfool said:


> Any update on this? I realize it might still be traveling halfway around the world to get to you, but I'm curious what you've found. Otherwise, PCBs like the Muzzle are a bit useless until there's a solution :-(


It worked! No problems at all, it's a nice surprise. I got this one if you're interested:








						14.88US $ |100% Original That4301s That4301 Ssop30 Integrated Circuit - Replacement Parts - AliExpress
					

Smarter Shopping, Better Living!  Aliexpress.com




					www.aliexpress.com


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## fig (May 19, 2021)

twebb6778 said:


> It worked! No problems at all, it's a nice surprise. I got this one if you're interested:
> 
> 
> 
> ...


Thanks for that. I just ordered a set.


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## Dali (May 20, 2021)

The Muzzle will never leave my board. I'm happy to see "alternative" seems to works so more people can enjoy that one.


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## Abyssmal (Jul 3, 2021)

twebb6778 said:


> It worked! No problems at all, it's a nice surprise. I got this one if you're interested:
> 
> 
> 
> ...


Hey i might buy one of theses, they still works fine in your pedal? Thanks


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## Abyssmal (Jul 3, 2021)

fig said:


> Thanks for that. I just ordered a set.


Did it work in your pedal you too? I ask because they might have different batches...


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## fig (Jul 3, 2021)

Norke said:


> Did it work in your pedal you too?


I haven't built it yet. It's in the queue!


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