Hey guys.
I built a MXR Phase 45 using not the 2N5952 transistors matched couple, but I tried two any J201 (when we get it easely!) and the effect worked fine immediately.
I would like to build the Phase 90, I don't want to buy a bunch of 2N5952 nor a matched transistors (a quartet) because the cost.
Now the J201 are not available in the shops I used to buy, so I decided to buy some SMD version, MMBFJ201, with the mini PCB. I read those are exactly the same thing.
Did someone try to use just J201 in the Phase 90?
Thanks!
I have played around a bit with the jfets in the circuit. I've had j201 working fine in this circuit but I remember their vgs off values were all over the place and harder to get matched sets. With the smd version there might be tighter tolerances.
With 4 jfets vs the 2 in the phase 45. It'll be harder to get lucky by just putting 4 random jets. Also keep in mind with 4 random jfets you might get phasing but with 4 matched ones the phasing will most likely be much deeper
Other alternatives that worked well for me 2n5457, 2n5458, bf245c and and 2sk30a
You can always try this if nothing works for you
http://tagboardeffects.blogspot.com/2012/07/jfet-matcher.html?m=1
In my experience, the smd j201s are extremely accurate in that they are pretty well all the same tolerances. Again, that's just in my experience, I used them in a harmonic tremolo.
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Thanks for your replies. ;)
I tried to search some furtrher information. A good replace (as in the Nom Nom Phase 90 replica) are the transistor used are the 2N5457. Even this transistors are becoming rather rare, but also this has its smd version.
Ok, this is the thing: I need 4 matched transistors, and it's hard to find a quartet of 2N5952 kit, and if I find one it's pretty expensive, especially looking the costs of just 4 transistors!
I could buy a bunch of 2N5457 smd (with the mini PCB and maybe the 3 Pin strip angled, adding costs!) and matchin them by myself. Considering that the smd should be most accurate (or it just a suspect?), how many transistor I could buy? 30? 40? 100?! ::)
Of course I would spend the same or even less than a quartet matched transistors. In this case I'll have a lot of transistors, but I could use them sometimes.
Thank you! :)
Hey Jack,
I guess it depends on your short-term goals and budget. If you want/need to build a working Phase 90 for next week's gig, spend the $ on the matched set.
You're paying for the time it takes to match the FETs. Matching FET's is kind of a pain.
OTOH, if your band just booked the gig for New's Year's Eve, you can buy a bunch ( at least 30 ), and match them yourselves.
Remember, SMD parts are super small. Resistors are about as big as fleas. If you breath on them too hard, they'll hop away and hide
in the carpet. Then, your matched quartet of SMD 2N5457's will go hunt them down! ;D ;D ;D ;D
:D
Anyway, the don't need a phase 90 soon, but it's a money thing, too.
Expensive quartet or expensive bunch of transistors trying my luck? ???
I noticed that Musikding, where I usually order, doesn't have available the quartet matched 2N5952, right now. Even if those could be available soon.
I'm trying some calculations. I need SMD MMBF5457 + PCB Adapter SMD. I will use the cut legs from other used components.
- For 20 pieces I'll spend less than the quartet matched.
- For 25 pieces I'll spend about the same than the quartet matched.
- For 30 pieces I'll spend more than the quartet matched.
The question is how much chance I'll have to get at least four MMBF5457 matched? ::)
Did someone try to match SMD transistor? Is it really easier?
I think it comes down to whether you are likely to need a lot of transistors in your inventory along with a few sets of matched transistors. If you are doing multiple builds of a pedal that needs them, then it makes sense to match the transistors yourself. If you only need a couple of matched pairs or quads, buying the sets may be a better use of your time and money.
Quote from: JackSkellington on July 31, 2018, 01:24:43 PM
I'm trying some calculations. I need SMD MMBF5457 + PCB Adapter SMD. I will use the cut legs from other used components.
- For 20 pieces I'll spend less than the quartet matched.
- For 25 pieces I'll spend about the same than the quartet matched.
- For 30 pieces I'll spend more than the quartet matched.
The question is how much chance I'll have to get at least four MMBF5457 matched? ::)
More info about the spread of the significant specs is needed. ( and for the love of all that's holy,
please do not provide that info ) :)
Just so you know, JMK PCBs has a 4 stage phaser project, and you can buy a version that comes with 4 matched 2N5952s.
Jacob
Thanks. ;) I'm considering even some kits, even if I never bought them.
Meanwhile, what JFET matcher vero layout can you, guys, advice me?
I'm looking this: http://tagboardeffects.blogspot.com/2012/07/greatly-improved-jfet-matcher.html
The updated version should be better, but I read several issue, too. ???
Hey Jack,
what is your budget?
My budget about what?
About the pedal, I try to spend less than I can because this is just an hobby, I usually don't spend for PCB, but I use stripboard layout, I don't buy coloured enclosure, that's it. I evaluate time by time every my order.
About the JFET matcher, I wouldn't spend for a tool, because my using should be rather rare. A simple good DIY project will be fine. ;)
Quote from: JackSkellington on August 03, 2018, 01:29:07 PM
My budget about what?
How much money are you willing to spend in order to arrive at a functioning Phase 90?
And when is your preferred completion date?
I used to order from Tayda and Musikding. I could spend what I have to spend to build it, trying to spend the less I can. Musikding, I don't know why, has the Phase 90 kit, but not the quartet 2N5952, not right now. I could make some calculation with the cost of the kit and the cost to buy every single part.
I don't have a date to finish it. Indeed, I'm not plainning to inlcude it in my next order. Except, I could include at least the 2N5952s matched or a 25-30 (or more?) MMBF2N5457s to match.
I would like manage the difficult of the matching (or matched) transistors.
Looks like your ship has come in, Jack.
https://www.musikding.de/The-Phaser-Phaser-kit (https://www.musikding.de/The-Phaser-Phaser-kit)
"This kit contains all parts you need to build a fully functional effect pedal."
Thank you, I'm considering right that. I still have to do some calculations because I think I can spend less if I buy the single part somewhere else.
Probably I'll buy the matched transistors. I just have to wait the availability there or in another shop.
Quote from: jimilee on July 26, 2018, 01:51:08 PM
In my experience, the smd j201s are extremely accurate in that they are pretty well all the same tolerances. Again, that's just in my experience, I used them in a harmonic tremolo.
Just wanted to confirm that experience: I just measured 10 SMD (MMBF201) and 10 TO-92 J201 and the tolerances on MMBFJ201 (SMD) are much tighter than on the traditional TO-92 J201. Measured using the runnoffgroove-Method (http://www.runoffgroove.com/fetzervalve.html).
The Range of the ROG measurement was:
average Vp: -0.83V (spanning from -0.57 to -0.97)
average Idss: 0.64mA (spanning 0.30mA to 0.83mA)
My Result:
100% of the SMDs are in the ROG-range.
0% of the "traditional J201 are in the range (probably all fake...)
Might be a question of sourcing as well, the SMDs are from Musikding (for sure), the J201 I am not sure about. Just ordered cheap ones from ebay, will measure those, when they arrive.
I could order the MMBFJ201, eventually, from Tayda, just because they are cheaper than the ones from Musikding.
I'm not talking about my Phase 90, but for any other project.
Meanwhile, I ordered a quartet of 2N5952. Not cheap, but it will work for sure.
Quote from: Marshall Arts on September 09, 2018, 09:42:42 AM
Quote from: jimilee on July 26, 2018, 01:51:08 PM
In my experience, the smd j201s are extremely accurate in that they are pretty well all the same tolerances. Again, that's just in my experience, I used them in a harmonic tremolo.
Just wanted to confirm that experience: I just measured 10 SMD (MMBF201) and 10 TO-92 J201 and the tolerances on MMBFJ201 (SMD) are much tighter than on the traditional TO-92 J201. Measured using the runnoffgroove-Method (http://www.runoffgroove.com/fetzervalve.html).
The Range of the ROG measurement was:
average Vp: -0.83V (spanning from -0.57 to -0.97)
average Idss: 0.64mA (spanning 0.30mA to 0.83mA)
My Result:
100% of the SMDs are in the ROG-range.
0% of the "traditional J201 are in the range (probably all fake...)
Might be a question of sourcing as well, the SMDs are from Musikding (for sure), the J201 I am not sure about. Just ordered cheap ones from ebay, will measure those, when they arrive.
Cool. I'll have to get some SMDs on my next Mouser order.