tone bender mkii build report

[jjoko]

Build Rating

3.00 star(s)

Hi.

Transistor (Peak DCA55)
Q1 (MP42B): hfe 70~75, leakage 150 µA
Q2 (MP20B): hfe 90~95, leakage 50 µA
Q3 (MP20B): hfe 110~115, leakage 200 µA

collector voltage (VCC: -9.3v)
Q1: -7.42v
Q2: -0.19v
Q3: -7.78v

I've just finished building a Tone Bender mkii pedal.

Using a trimpot to control the Q2 bias is a common technique in Tone Bender builds.
Exposing the Q3 bias externally is also helpful for tone control.
When it comes to germanium transistors, buying them in bulk from eBay is usually a better deal than buying small matched sets.

The MP20B is a great transistor for Tone Benders because you can find ones with an hfe of 100+ relatively easily.

Sorry about my English.
Google Translate helped me with writing this.
Thanks!

 

[Jiberjew]

Looks great! Where did you find that style of DC jack?? I'll search Tayda for sure! I like that you can remove it to MOD the PCB if needed. Although, it does stick out pretty far. Either way, pretty cool!

 

[jwin615]

Looks great! Where did you find that style of DC jack?? I'll search Tayda for sure! I like that you can remove it to MOD the PCB if needed. Although, it does stick out pretty far. Either way, pretty cool!

Outies

 

[jjoko]

Looks great! Where did you find that style of DC jack?? I'll search Tayda for sure! I like that you can remove it to MOD the PCB if needed. Although, it does stick out pretty far. Either way, pretty cool!

https://www.taydaelectronics.com/dc-power-jack-2-1mm-enclosed-frame-with-switch-external.html

I think you'll really like this.

 

[Jiberjew]

https://www.taydaelectronics.com/dc-power-jack-2-1mm-enclosed-frame-with-switch-external.html

I think you'll really like this.

Very nice!! I had a huge Tayda order, so I added a bunch of these. Can't wait to try these out! Thanks!

 

[Alan W]

Looks great! Where did you find that style of DC jack?? I'll search Tayda for sure! I like that you can remove it to MOD the PCB if needed. Although, it does stick out pretty far. Either way, pretty cool!

You can always stick a few washers on the interior, so it doesn’t poke out if that becomes an issue.

 

[DRBEN]

I like your work!


A few weeks ago I also started my adventure with germanium transistors. I had built modulations before, and the topic of distortion was foreign to me.

 

[Feral Feline]

Solid build.

Thanks, jjoko, for the Ge bulk-buy advice. I've bought matched sets in the past, but will buy in bulk in future.



@Jiberjew — I prefer the outties myself, and they may look a little fugly on a completed build on its own, once you plug in the audio and power cables it looks just fine AND the interior gutshot of the pedal looks better with an outty AND you have more room for mods (switchesk, a 9mm pot etc) AND as you've astutely observed you can pull the whole circuit out for said mods or troubleshooting or re-doing the enclosure graphics without having to desolder anything.

NOTA BENE: there are two levels of quality to the assortment of outties, good and bad. The bad ones will crap out sooner than later if you apply too much heat while soldering them, I've had to replace a couple of cheapo outties — intermittent power trouble-shooting is a PITA. So...
Spend a little more and get the better ones! How can you tell if the more expensive ones you're getting are just the same as the bad cheaper ones? Time will tell, I guess, but if you see a vendor with what looks to be the same damn thing but one is cheaper, GET THE PRICIER ONES!

 

[PedalBuilder]

@Jiberjew — I prefer the outties myself, and they may look a little fugly on a completed build on its own . . .

It doesn't have to be fugly. If you use one nut on the inside and one on the outside, you can set it up so that the outie jack is flush with the enclosure and looks classy. And they don't have to be expensive to be good. I get mine for about 8¢ each on Ali Express, and they haven't had a single issue.

 

[Feral Feline]

That does indeed look good, PedalBuilder!

I don't think they're fugly at all, personally I like them both functionally and aesthetically.

Also, 8¢ beats any vendor-price I've seen so far, even the cheap&inexpensive ones I ordered from Taobao when I was living in Hong Kong.

​

 

[Jiberjew]

Solid build.

Thanks, jjoko, for the Ge bulk-buy advice. I've bought matched sets in the past, but will buy in bulk in future.



@Jiberjew — I prefer the outties myself, and they may look a little fugly on a completed build on its own, once you plug in the audio and power cables it looks just fine AND the interior gutshot of the pedal looks better with an outty AND you have more room for mods (switchesk, a 9mm pot etc) AND as you've astutely observed you can pull the whole circuit out for said mods or troubleshooting or re-doing the enclosure graphics without having to desolder anything.

NOTA BENE: there are two levels of quality to the assortment of outties, good and bad. The bad ones will crap out sooner than later if you apply too much heat while soldering them, I've had to replace a couple of cheapo outties — intermittent power trouble-shooting is a PITA. So...
Spend a little more and get the better ones! How can you tell if the more expensive ones you're getting are just the same as the bad cheaper ones? Time will tell, I guess, but if you see a vendor with what looks to be the same damn thing but one is cheaper, GET THE PRICIER ONES!

Nice. Great advice. I ordered some cheap ones at Tayda, as they only had one type that I saw. I will look on small bear, they probably have better for sure. On that note, I've noticed at Tayda that you get what you pay for on certain parts. It seems like the IC'c and transistors are hit and miss. I've been going to amplified parts a lot as well, but the packaging is kind of bad. But, I'll check them as well.

 

[Jiberjew]

You can always stick a few washers on the interior, so it doesn’t poke out if that becomes an issue.

Great idea! Thanks!