DSL100HR Bias Help

[ehehat]

Seems like it should be easy AF to bias this thing so I must be an idiot. Do I have a bad/wrong multimeter? Everywhere I've looked it says to use mV and set somewhere around 70/76mV but when I hook this thing up I get .2-.3. When I use VDC I get like .032 or some crap. What the hell am I doing wrong here? Thanks!

 

[Kutt]

What you're doing looks correct. Is the amp out of Standby (in "play" mode) while you're getting that reading?

 

[ehehat]

What you're doing looks correct. Is the amp out of Standby (in "play" mode) while you're getting that reading?

Yes, It's in "full" mode. connected to speaker cab. Same reading whether I have a cable in the input or not.

 

[Kutt]

I'm not an amp tech so my input will be minimal here, but I have the same amp and have biased it exactly like you're trying to do. My multimeter is not auto ranging, I hard set it to the 200mV setting. Do you happen to have a second multimeter you can test with to rule out if it's the Fluke?

You probably did this but also make sure your test leads are plugged into the correct ports on the Fluke. Apologies in advance for asking the obvious.

 

[ehehat]

I'm not an amp tech so my input will be minimal here, but I have the same amp and have biased it exactly like you're trying to do. My multimeter is not auto ranging, I hard set it to the 200mV setting. Do you happen to have a second multimeter you can test with to rule out if it's the Fluke?

You probably did this but also make sure your test leads are plugged into the correct ports on the Fluke. Apologies in advance for asking the obvious.

No man, Really appreciate the input! I dont have another multimeter but think I may try to order something different. If I may ask.. What do you use? Again, thanks!

 

[Kutt]

I have a Klein MM100 digital multimeter. I got it at Home Depot about 6 years ago. Fluke is a reputable brand as you probably know, but there could in fact be something wrong with yours.

Another obvious suggestion, but if you have another tube amp you could try measuring that one too. If the Fluke acts up there as well, then it's not a fluke. (See what I did there?!)

 

[ehehat]

I have a Klein MM100 digital multimeter. I got it at Home Depot about 6 years ago. Fluke is a reputable brand as you probably know, but there could in fact be something wrong with yours.

Another obvious suggestion, but if you have another tube amp you could try measuring that one too. If the Fluke acts up there as well, then it's not a fluke. (See what I did there?!)

Ha! Nice one! Thanks for the help!

 

[South Park]

You have it on the wrong setting you need it DC not AC . You need amp meter not voltage reading .

 

[ehehat]

You have it on the wrong setting you need it DC not AC . You need amp meter not voltage reading .

Based on the pic of the dial I uploaded, what setting should it be on? I tried it on V DC and It read something like 0.032, would that then be 32mV? Or do I need to get a different meter? Thanks for your input!

 

[fitz288]

Here's a shot of my meter on a probe when I was balancing the 6V6 tubes on my Haze.
Mostly irrelevant, except the meter setting.

 

[ehehat]

Here's a shot of my meter on a probe when I was balancing the 6V6 tubes on my Haze.
Mostly irrelevant, except the meter setting.
View attachment 98326

And mine doesn't read mA. I was on Eurotubes and their how-to vid says you can use the bias points set at mV. Doesn't seem like this should be so difficult. lol

 

[fitz288]

And mine doesn't read mA. I was on Eurotubes and their how-to vid says you can use the bias points set at mV. Doesn't seem like this should be so difficult. lol

I think your meter is probably good for other stuff around the house, but perhaps a better meter for your amp(s) would be a good idea.

 

[pedecamp]

Seems like it should be easy AF to bias this thing so I must be an idiot. Do I have a bad/wrong multimeter? Everywhere I've looked it says to use mV and set somewhere around 70/76mV but when I hook this thing up I get .2-.3. When I use VDC I get like .032 or some crap. What the hell am I doing wrong here? Thanks!

View attachment 98317 View attachment 98318

Measure something simple like a 9v battery or something to make sure your meter is working properly. Put new batteries in your meter too. You got the amp warmed up and in play mode right?

 

[ehehat]

Measure something simple like a 9v battery or something to make sure your meter is working properly. Put new batteries in your meter too. You got the amp warmed up and in play mode right?

Yes absolutely. I'll check something else tonight. Is there a consensus that it needs to be reading DC voltage and not AC?

 

[WiderGates]

Set your meter to V and DC,
not A and AC, not V and AC, not A and DC.

.032V is 32mV

 

[ehehat]

Set your meter to V and DC,
not A and AC, not V and AC, not A and DC.

.032V is 32mV

Thank you. Are you 100% certain of this?

 

[WiderGates]

Yes.

My DSL100HR sounds best with 64mV per side.

 

[Kutt]

Ah! I missed the "AC" on your picture. Yes, it needs to be DC volts. I just double checked my Klein meter as a sanity check.

 

[Kutt]

This is the appropriate setting on mine:

 

[ehehat]

This is the appropriate setting on mine:

View attachment 98327

AWESOME! Thanks everyone!