3PDT Footswitches

Alvin

Does anybody know which ones are worth buying ?
     The blue ones you see everywhere go from just over £1.00 to silly prices  and they are all non branded and look exactly the same .  Are they all coming out of the same factories ?  
     I am trying to find decent quality ones but is hard to know which ones to go for , the Fulltone are supposed to be good but they seem to be about £10.00 which is a bit excessive for a hobbyist , at that price i am thinking just keep buying the cheap ones and if they have to be changed  then fine .   I believe the Belton ones are good also,  but i can't find a supplier for those .  
    Any suggestions ?

Kalimna

For my home pedal builds, I have bought on eBay whichever is the cheapest. Most are the blue-bodied ones, but some are black. I am not sure I notice much of a difference between those and the more expensive ones. Having said that, my pedals are hardly subject to rigorous use.
If you are just having a go at making some pedals for a hobby, buy the cheap ones. If you intend selling them, then perhaps spending more for future reliability is sensible.

Adam

ICBM

None of them.

Adam_MD

ICBM said:

None of them.

Absolutely this but if it has to be 3pdt then the alpha ones are as good as I've found.  

https://www.tube-town.net/ttstore/Switch/Footswitch-Standard/Alpha-Footswitch-3PDT-Latching::3695.html?language=en

If you have the room in your enclosure I prefer optical switching using a dpdt.  It's a little more expensive but a lot more reliable in the long run.

http://shop.pedalparts.co.uk/OptoPuss_-_Optical_True_Bypass/p847124_17567620.aspx

http://1776effects.com/product/opto-tron-optical-bypass/

menamestom

Better off with a DPDT switch and optical bypass board.   DPDT’s, while still mechanical should last longer by virtue of having lees mechanical parts in side.

http://shop.pedalparts.co.uk/OptoPuss_-_Optical_True_Bypass_PCB/p847124_17567616.aspx

aord43

Adam_MD said:

ICBM said:

None of them.

Absolutely this but if it has to be 3pdt then the alpha ones are as good as I've found.  

https://www.tube-town.net/ttstore/Switch/Footswitch-Standard/Alpha-Footswitch-3PDT-Latching::3695.html?language=en

If you have the room in your enclosure I prefer optical switching using a dpdt.  It's a little more expensive but a lot more reliable in the long run.

http://shop.pedalparts.co.uk/OptoPuss_-_Optical_True_Bypass/p847124_17567620.aspx

http://1776effects.com/product/opto-tron-optical-bypass/

Thanks for the pedalparts.co.uk link, I'd not seen that one before.

ICBM

That's a halfway house that still uses a mechanical switch though, and it's still in the signal path for the output side switching. Those Alpha DPDTs aren't that much more reliable than a 3PDT either.

Surely it cannot be too difficult to build an optical switching system that uses a Boss-style flip-flop circuit to operate the optos, hence allowing a momentary SPST switch to be used… that would give the advantages of the Boss switching system without the disadvantage of the not-quite-unity-gain buffers.

Adam_MD

Genuine question @ICBM have you seen many faulty alpha dpdt vs those Taiwan blue 3pdt?  the only pedals I've had problems with have had 3pdt and I haven't heard of any reliability problems with the alpha dpdt.  

ICBM

Yes, I've changed plenty of them too. I'm not sure of the relative numbers, but easily enough that I don't consider the Alpha switch to be really reliable either.

I suppose I just don't understand the re-acceptance of mechanical switching in the signal path. This problem was solved forty years ago, and although the solution is not perfect it just needed a bit of improvement. Mechanical switching is a totally backwards step.

Adam_MD

Interesting I've never heard of issues with the alpha dpdt before.  From a DIY perspective the only other option is relay bypass but then it is starting to get expensive.  

ICBM

Adam_MD said:

From a DIY perspective the only other option is relay bypass but then it is starting to get expensive.  

And sucks battery life badly, as well as having all of the disadvantages of mechanical switching except reliability.

That's why there needs to be a simple, one-hole-mounting, momentary-SPST-operated optical system available - like the OptoPuss but fully optical.

Adam_MD

ICBM said:

Adam_MD said:

From a DIY perspective the only other option is relay bypass but then it is starting to get expensive.  

And sucks battery life badly, as well as having all of the disadvantages of mechanical switching except reliability.

That's why there needs to be a simple, one-hole-mounting, momentary-SPST-operated optical system available - like the OptoPuss but fully optical.

If you can design it I'll try it.  I'm always up for trying new things in pedals.

ICBM

I'm not much of a circuit designer, but it shouldn't be too difficult for someone who's good at it.

jpfamps

The new optical switches are generally based on the H11F1M photo FETs. 

These have good "offness", but are typically around 100-200 ohms when on, which is probably OK, but may cause problems if several pedals are connected in series. I don't have an answer to this.

We had a look at these as an optocoupler substitute for trem or compressor say, but didn't find them that easy to use as variable resistors.

To do a momentary switch activated DPDT photo FET based switch (you would only need DPDT as you can drive an LED from the flip flop) you would need some form of electronic flip flop (there are very good reasons to use the BOSS flip flop....), and two photo FETs. This may require SMD to make it small enough as this would require quite a few components, and thus not idea for a DIY project, although I do know people who do DIY SMD.......

Not difficult to do at all, but may be difficult to make small enough to replace a 3PDT.

m_c

I've done DIY SMD. It's not that hard with the right equipment, which doesn't even have to be that expensive.
Temperature controlled heat gun stations can be had for £30 (it's highly recommended you do dismantle and check cheap ones to make sure the wiring is properly connected, as there are several reports of earth wires not being connected).
The biggest problem is the required solder paste, as it goes off. It's not like a roll of solder that can sit on the shelf for years and still be used. I end up buying £15 syringes, then only using about 50p worth of paste.

I'm no circuit design expert, but I have designed and built a few SMD PCBs. I could probably design something using miniature relays. By miniature, I mean SMD chip sized relays designed for audio signal switching, which I even have in a box somewhere...

The big problem with using most mechanical switches, is if they're only switching a fraction of their rated current/voltage, the contacts oxidise. Switch and relay contacts rely on arcing to clean the contacts. If you don't get enough arcing, then they gradually oxidise/get contaminated. Gold contacts do help alleviate the problem as they don't oxidise, but you have to make sure they stay clean.

m_c

Regarding the Boss switching, I thought the mechanical switch was latching, so you don't need a flip flop circuit?

Adam_MD

Fascinating chaps.  I have two pcbs here which use smd parts but I've not felt brave enough to have a go yet.  I need to get used to working with smd because all of the through hole fets are obsolete and will soon only be available in smd form.

ICBM

m_c said:

Regarding the Boss switching, I thought the mechanical switch was latching, so you don't need a flip flop circuit?

No, the Boss switch is momentary. It's actually a keyboard (computer, not piano!) type switch - it's incredibly reliable because all that happens when it's operated is that a plastic plunger with an angled face slides past a metal spring contact and gently pushes it sideways.

They almost never fail - I'm pretty sure I've only ever changed four in the whole 30+ years I've been repairing gear. The most recent was actually only a week ago, and was because someone had somehow broken off the top of the plunger - the actual switch part itself was still working perfectly. It is possible that this could become more common - it was a very old DS-1, and the plastic may become brittle after 35 years or so.

Alvin

  Some interesting ideas here , i think optical is the way Lovepedal do there's . I had to change the momentory switch in one of them which was the easiest job ever with only two wires .
     I think i will stick with the 3pdt as i can wire them up pretty quick now so if they do pack up (which some have)they  are still pretty easy to change .    You are all saying what i though about them not being great quality but there must be a decent one somewhere ? 

Adam_MD

Alvin said:

  Some interesting ideas here , i think optical is the way Lovepedal do there's . I had to change the momentory switch in one of them which was the easiest job ever with only two wires .
     I think i will stick with the 3pdt as i can wire them up pretty quick now so if they do pack up (which some have)they  are still pretty easy to change .    You are all saying what i though about them not being great quality but there must be a decent one somewhere ? 

As I said earlier the Alpha 3pdt are definitely
 better than the Taiwan blues.  A bit more expensive but worth it.  

jpfamps

Using keyboard switches a la BOSS is better than most momentary switches as they have been optimized for low mechanical bounce.

The momentary switches used by Line 6 are also low bounce too (although not as reliable).

In my experience the standard BOSS flip flop requires a bit of component value jiggling when using other style of switches.

I can draw up a schematic for the BOSS flip-flop with optical switching if anyone is interested.