Dave Hall Amp's Response To Popping Problem - hmmmm?

[xray]

Referring to the DHA VT1-EQ-Bassdriver:

"....all normal"? (see below email exchange) Well I thought I'd check in with the experts - I have nothing negative to say about the abilities of the pedal, but the popping is really ridiculous. It sounds like I'm going to blow my cabinet! Is this really a normal occurrence from "true bypass" pedals.

If so, I guess all the pedals I have that claim to be "true bypass" must be lying because none of the these pedals have this sever popping problem.

DHA - USA Response
Hi David -
That is a normal side effect of true bypass pedals...no problem...you should also hear a pop w/ boost when engaged...all normal...
JR


On Jun 15, 2010, at 1:31 PM, David wrote:


Hi, just got my VT1 and there’s some serious popping when switching between on/off (stomp switch) or any of the switches at the top of the box. Chain is currently: Gibson T-Bird (rounds)>VT1> Ampeg SVT-CL> Eden 410XLT. Is this normal?
Thanks,
David

[rratajski]

I have had pedals that popped lightly before, some not so lightly. I've even built pedals that popped so loud that I couldn't sell them to the customer like that.
My g****rist in my band just got a vintage ri rat that pops when engaging, so it's possible. It is just a side effect of TB...

[()smoke()]

i've found that occurs most always with true hard-bypass pedals, in my experience

[bigchiefbc]

It is normal with true-bypass pedals, but there are things you can do to minimize the popping, which its possible Dave hasn't done on his pedals.

The main cause of the popping is that the input capacitor has a bunch of stored voltage in it (that is what capacitors do). When the pedal is bypassed, there is nothing drawing this voltage out, so it just sits there until you turn the pedal on again. That is when all of that voltage is released, and you get a POP.

The primary method of lessening this popping is by using a pull-down resistor. It is a resister that is wired to the input side of the cap and the other end of the resistor goes to ground. This pulls all of the voltage out of the input cap and leeches it to ground. It is an extremely easy mod, that I'm sure a ton of people around here could do for you if you're not comfortable.

[bongomania]

First, bigchiefbc is right, and Dave Hall was telling the truth. Those are facts.

The reason you have not experienced this popping before has exactly nothing to do with whether your other pedals are true bypass, and there are several reasons for this:
--There are different types of true bypass.
--There are different methods of minimizing the popping.
--The popping is dependent on many external factors, and is usually not the fault of the pedal.

There's more to discuss of course, but these base-line things needed to be said.

[MAMMOTHvolume]

Originally Posted by bongomania

First, bigchiefbc is right, and Dave Hall was telling the truth. Those are facts.

The reason you have not experienced this popping before has exactly nothing to do with whether your other pedals are true bypass, and there are several reasons for this:
--There are different types of true bypass.
--There are different methods of minimizing the popping.
--The popping is dependent on many external factors, and is usually not the fault of the pedal.

There's more to discuss of course, but these base-line things needed to be said.

what?

[JanusZarate]

Originally Posted by MAMMOTHvolume

what?

He's right.

I've come across popping on occasion with some true bypass pedals... it's usually damn-near random, and just when you think you've figured out a possible external factor, the popping stops altogether.

It's partly why I love relay-based designs and buffered bypass circuits, but in a world where many buffered bypass designs sound progressively worse when stacked, I can't blame some for opting for true bypass instead... especially since it's relatively cheap, clean, and effective.

[B.C.]

Originally Posted by bongomania

First, bigchiefbc is right, and Dave Hall was telling the truth. Those are facts.

The reason you have not experienced this popping before has exactly nothing to do with whether your other pedals are true bypass, and there are several reasons for this:
--There are different types of true bypass.
--There are different methods of minimizing the popping.
--The popping is dependent on many external factors, and is usually not the fault of the pedal.

There's more to discuss of course, but these base-line things needed to be said.

Right on.

[bongomania]

Originally Posted by MAMMOTHvolume

what?

Just for reference, here's an amusing post by this same person, using a different account name: True Bypass - just hype?

[Joe Gress]

One thing I have noticed with all my true bypass pedals is that when I first turn them on they have a ridiculous pop to them. After a few minutes of them "warming up", and me turning them on and off for a bit, the pop seems to go away.

[xray]

I have noticed it does subside after I engage it the first time. (The cap probably discharges at this point). However, I can't believe big time musician would tolerate this during gigs. Also will it hurt the speakers?

[bongomania]

Big timers either tolerate it, or they use buffered or relay-based bypass switching units instead of the popping 3PDT switch. You'll see the pedalboards of the biggest touring artists often fall into one of three categories:

--All or mostly Boss pedals (if one craps out, you can easily score a replacement on the road, and it will sound exactly like the one you had).
--"Whatever" (see Flea for example). No concern for tech stuff.
--Elaborate professional switching and routing systems that are used for bypass instead of whatever bypass switching is in the pedal. These are the ones with relays and high-end buffers. CAE, Voodoo Labs, Pete Cornish, etc.


Yes, a loud pop can hurt your speakers if you amp is cranked up.

[xray]

Originally Posted by bongomania

Yes, a loud pop can hurt your speakers if you amp is cranked up.

Well, with a brand new cab I'm not going to chance that! Guess I'll have to try Big Chief BC recommendation and add a pull-down resistor. Is 1M 1/4w good enough?

Thanks all.

[JanusZarate]

Originally Posted by bongomania

Yes, a loud pop can hurt your speakers if you amp is cranked up.

I've always wondered about how often techs see speakers which have blown due to true bypass pops, compared to other causes of speaker destruction. I imagine it can't be that common in practice... I haven't met or talked to anyone yet who's lost a speaker this way yet.

I fall into the "whatever" camp, but then again, I've had some fairly positive experiences with true bypass pedals. I did get some pops from an EHX Stereo Clone Theory, but that's about all I can recall.

I've had worse pops from old amps when turning them off.

[KarateKid25]

Originally Posted by MAMMOTHvolume

what?

What what? As a 'pedal / amp builder' you do understand DC offset, right?

[DHA]

Originally Posted by xray

Referring to the DHA VT1-EQ-Bassdriver:

"....all normal"? (see below email exchange) Well I thought I'd check in with the experts - I have nothing negative to say about the abilities of the pedal, but the popping is really ridiculous. It sounds like I'm going to blow my cabinet! Is this really a normal occurrence from "true bypass" pedals.

If so, I guess all the pedals I have that claim to be "true bypass" must be lying because none of the these pedals have this sever popping problem.

DHA - USA Response
Hi David -
That is a normal side effect of true bypass pedals...no problem...you should also hear a pop w/ boost when engaged...all normal...
JR


On Jun 15, 2010, at 1:31 PM, David wrote:


Hi, just got my VT1 and there’s some serious popping when switching between on/off (stomp switch) or any of the switches at the top of the box. Chain is currently: Gibson T-Bird (rounds)>VT1> Ampeg SVT-CL> Eden 410XLT. Is this normal?
Thanks,
David

Time to put the record right.

Dave did not reply, the USA rep JR did. But saying that he is correct.

I do have a pull down resistor that helps. Pop can be a lot more of a problem in some set ups than others. Other pedals or active basses charge the input cap in some cases. Poor or long cables can also be an issue. There is also the issue of the output level, the popping we are talking about is an issue with the input cap on the pedal, but if the output level is very high (not normally an issue with tube amps) then a level change is heard when the bypass is pressed. Does it pop with unity gain?

But, try this...

On power up of the pedal turn down the level to zero or switch the amp off, but the cable needs to be plugged in from the pedal to the amp. operate the by-pass footswitch 10-20 times as quick as you can, this discharges the input cap.

hope that helps.

[DHA]

Originally Posted by xray

Well, with a brand new cab I'm not going to chance that! Guess I'll have to try Big Chief BC recommendation and add a pull-down resistor. Is 1M 1/4w good enough?

Thanks all.

already got one. But add another if you want as it will dump the charge twice as quick

[jgroh]

Originally Posted by DHA

Time to put the record right.

Dave did not reply, the USA rep JR did. But saying that he is correct.

I do have a pull down resistor that helps. Pop can be a lot more of a problem in some set ups than others. Other pedals or active basses charge the input cap in some cases. Poor or long cables can also be an issue. There is also the issue of the output level, the popping we are talking about is an issue with the input cap on the pedal, but if the output level is very high (not normally an issue with tube amps) then a level change is heard when the bypass is pressed. Does it pop with unity gain?

But, try this...

On power up of the pedal turn down the level to zero or switch the amp off, but the cable needs to be plugged in from the pedal to the amp. operate the by-pass footswitch 10-20 times as quick as you can, this discharges the input cap.

hope that helps.

Cool, thanks for the tip. I have a DHA VT1-MK3 pedal with a boost built into it, and I was extremely concerned when once I had it engaged, there was a loud pop when trying to switch off the pedal. I emailed Dave and he told me it was normal. I fortunately dont have to use the boost often, and it doesnt pop when its not on, so Ive been ok, but Ill try this tip out though!

[DHA]

Originally Posted by JanusZarate

I've always wondered about how often techs see speakers which have blown due to true bypass pops, compared to other causes of speaker destruction. I imagine it can't be that common in practice... I haven't met or talked to anyone yet who's lost a speaker this way yet.

I fall into the "whatever" camp, but then again, I've had some fairly positive experiences with true bypass pedals. I did get some pops from an EHX Stereo Clone Theory, but that's about all I can recall.

I've had worse pops from old amps when turning them off.

good point

I have never understood how a pop can damage a speaker, not saying its a good thing but how can it? The pop can only produce a spike of noise to the max volume of the amp, the amp will limit the level of the power as it can't produce levels above its power supply rails. So if you have a 100W amp you get a 100W pop worst case. If you are using cabs that can't handle max volume of the amp then yes the pop will damage them but so will turning the amp up to max.

Might be wrong but someone show me the maths.

[Mr. Foxen]

I've seen an amp broken by pop. Someone left a can of it on top.

If you have a drummer, and you switch on a beat, the pop will just meld with drum sounds.