# Anyone contemplating using J201s for xc phaser?



## Paradox916 (Aug 21, 2021)

Them 2N5952 And equivalents are hard to get a hold of these days anyone give SMD subs a go like the the J201? Just curious.


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## benny_profane (Aug 21, 2021)

Try the 2n5457 SMD equivalents instead. J201 don’t have a compatible Vgs range.


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## Paradox916 (Aug 21, 2021)

I couldn’t find those I stock anywhere ether


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## benny_profane (Aug 21, 2021)

So, they need to be matched for the effect to work properly. Unless you have a stash, it’ll be quite a gamble to buy four and expect them to work. SMD devices usually have a closer distribution, but that doesn’t help if you can’t find them. I’d suggest getting a matched set from small bear or lectric fx. 









						Matched JFETs For Phasers - SGD Pinout
					

Small Bear Electronics DIY Parts




					smallbear-electronics.mybigcommerce.com
				












						Jay-Fetz - Singles, Matched Pairs, Quads - Lectric-fx
					

These are simply tiny pcb’s with SOT-23 JFETs already soldered on.  You just add your own leads and that’s it. Now you are ready to use it as a through hole part! Available in J102 (mmbfj201) and 2N5457 (mmbf5457).  Are you looking to build a phaser?  The 2N5457 variety are available in matched...




					lectric-fx.com


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## finebyfine (Aug 21, 2021)

benny_profane said:


> Try the 2n5457 SMD equivalents instead. J201 don’t have a compatible Vgs range.



any idea what other jfets are compatible with the circuit? I've been trying to find a list in case I don't have mmbf25457 matches


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## Paradox916 (Aug 21, 2021)

Damn near ever equivalent I have seen mentioned is out of stock or you are looking at around $20 bones for them I thought I would just get a bunch and learn a new skill them have extra stock.. but it’s slim pickings out there.


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## Robert (Aug 21, 2021)

I used four random unmatched MMBF5457's (from Tayda) for testing the XC Phase prototype.  (Which explains me not catching the reversed pinout on the silkscreen)

It worked perfectly fine, in fact, surprisingly well considering I didn't bother with matching them in any way. 

The phasing might be more "lush" with a matched set, I certainly won't dispute that, and maybe I got lucky, but it was good enough for rock 'n roll. 🤘


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## benny_profane (Aug 21, 2021)

It’s difficult to name specific part numbers because JFET manufacturing tolerances vary widely. The published Vgs(off) parameter for the 2n5457, for example, is -0.5V to 6.0V, whereas the 2n5952 is -1.3V to -3.5. 

Without changing the zener diode, you’ll want devices with tightly matched Vgs values within the range of -1V or 1.5V to -3.0V. 

Again you’re far more likely to get consistent batches of SMD devices than TO-92 packages.

So, take a look at the data sheets of what is available and consider that along with available stock, price, and how comfortable you are with taking the measurements. Or get a matched set and call it a day. (Or be a madman and solder whatever you’ve got in blind!)


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## Feral Feline (Aug 22, 2021)

I get my matched sets from Lectric-FX 

I even made a special request for a six-matched set for a Maestro PS-1A build, Keefe was very accommodating.


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## Barry (Aug 22, 2021)

Paradox916 said:


> Damn near ever equivalent I have seen mentioned is out of stock or you are looking at around $20 bones for them I thought I would just get a bunch and learn a new skill them have extra stock.. but it’s slim pickings out there.


Where you located? I may have something


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## Bobbyd67 (Aug 22, 2021)

Holy crap even mouser is out of 5457 smd xD that's where I usually get mine :/


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## Harry Klippton (Aug 22, 2021)

Pedalhacker has  through hole 2N5457s for $1 a piece currently. 3800 in stock. I bought a stash a couple weeks ago 



			Pedalhacker Electronics - Guitar Pedal Components


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## finebyfine (Aug 22, 2021)

Robert said:


> I used four random unmatched MMBF5457's (from Tayda) for testing the XC Phase prototype.  (Which explains me not catching the reversed pinout on the silkscreen)
> 
> It worked perfectly fine, in fact, surprisingly well considering I didn't bother with matching them in any way.


Last time I measured mmbf5457's with my peak I was pretty floored at how close they were, to the point that until this thread I thought I must have been misunderstanding how to match JFETs.



benny_profane said:


> Without changing the zener diode, you’ll want devices with tightly matched Vgs values within the range of -1V or 1.5V to -3.0V.


Thank you so much for the info (only quoting a hair to not clog up the thread - anyone else should read the reply in full!)

Quest Components (USA based) - who I've never heard of before so I can't personally vouch one way or the other - has mmbf5457s in stock w/ a MOQ of 24 that comes out to $5, which is great deal given what the prices are listed at for places out of stock. That's about what I've paid for them before the recent price increases.


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## Barry (Aug 22, 2021)

finebyfine said:


> Last time I measured mmbf5457's with my peak I was pretty floored at how close they were, to the point that until this thread I thought I must have been misunderstanding how to match JFETs.
> 
> 
> Thank you so much for the info (only quoting a hair to not clog up the thread - anyone else should read the reply in full!)
> ...


$25 minimum order

Edit: Well it only took me 5 minutes to spend $70


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## finebyfine (Aug 22, 2021)

Barry said:


> $25 minimum order


ah shit didn't notice that


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## Barry (Aug 22, 2021)

Barry said:


> $25 minimum order
> 
> Edit: Well it only took me 5 minutes to spend $70


I bought plenty of the 5457's if anyone one needs some


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## BeeSharp (Oct 1, 2021)

I was getting through hole 2n5457 from mouser, but they're out....Tayda out too.


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## Barry (Oct 1, 2021)

BeeSharp said:


> I was getting through hole 2n5457 from mouser, but they're out....Tayda out too.


These ended up being SMD


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