Mesa d800 and passive basses causing distortion/overdrive

[Jack Torrance]

I recently purchased a used Mesa d800 and am having a hell of a time getting anything but distortion/overdrive out of it. I am pretty new to bass playing and it took me a while to get my active basses to sound good, but man after I figured it out the Mesa sounds AMAZING! Anyway I have an Epiphone thunderbird and it sounds horrible. I can’t seem to find a good setting. Has anyone ever come across this situation? This bass has stock pups, while my P and J basses have active EMG’s. My previous amp was a GK mb200 which is pretty straightforward. Oh I am playing through a GK cx210 400 watt cab. Any comments are appreciated!

 

[roccobass]

Have you tried the Epiphone on another rig and see how that sounds? Could be those passive pickups and that you just like active ones. Make sure you have right switch setting set (passive vs active) on the D800 control on front too.

An overlooked Subway amp technique to sort of create a bit of a fatter sound is to adjust the impedance switch on the back. If you’re running an 8 ohm or 4 ohm load (I.E.: one 8 ohm cab or two 8 ohm cabs or just one 4 ohm cab) you can switch the ohm switch to 2 in back. It’s kind of a power dampener, but I notice a fatter sound. It also decreases power output. Instead of 400 watts with an 8 ohm cab, now you’re at 300 watts. 600 watts with 4 ohm cab/Or two 8 ohm cabs instead of 800.

 

[Parzival]

That is weird. You would think you would have the opposite happen. If the d800 can handle the active basses ok, I don't see why it would distort with a passive bass.

 

[Jack Torrance]

Have you tried the Epiphone on another rig and see how that sounds? Could be those passive pickups and that you just like active ones. Make sure you have right switch setting set (passive vs active) on the D800 control on front too.

An overlooked Subway amp technique to sort of create a bit of a fatter sound is to adjust the impedance switch on the back. If you’re running an 8 ohm or 4 ohm load (I.E.: one 8 ohm cab or two 8 ohm cabs or just one 4 ohm cab) you can switch the ohm switch to 2 in back. It’s kind of a power dampener, but I notice a fatter sound. It also decreases power output. Instead of 400 watts with an 8 ohm cab, now you’re at 300 watts. 600 watts with 4 ohm cab/Or two 8 ohm cabs instead of 800.

The thunderbird sounds great on my GK mb200 rig…

 

[Jack Torrance]

That is weird. You would think you would have the opposite happen. If the d800 can handle the active basses ok, I don't see why it would distort with a passive bass.

That’s exactly what I was thinking. Just remembered I have another passive bass I’ll try when I get home

 

[roccobass]

The thunderbird sounds great on my GK mb200 rig…

You might also want to pose your question to the guys on this thread. See if they have some insight.

Thunderbird Club

 

[Parzival]

That’s exactly what I was thinking. Just remembered I have another passive bass I’ll try when I get home

Sounds like your Thunderbird needs a good talking to Mr. Torrance, if you don't mind my saying so. Perhaps a bit more.

 

[agedhorse]

First, try another bass to rule out the possibility that the problem is with the bass.

Further troubleshooting… when the distortion occurs, where are the knob settings? What is happening with the input O/L LED and output LIMIT LED?

It is possible that your amp got damaged in shipping, or being dropped. It happens sometimes, and this is a common symptom. Was the amp shipped in the factory box? Was the front of the amp well protected?

You can PM me for help, we can get it sorted out.

 

[Lance Bunyon]

Show us a picture of your EQ settings.
In any case, lower the gain and lower the bass and see what that does.
It's like chicken soup, it couldn't hurt.

 

[lermgalieu]

As stated above, lower the input gain, check your active/passive switch (try it both ways). Remove anything in the signal path other than your bass and the amp when troubleshooting.

 

[Jack Torrance]

Sounds like your Thunderbird needs a good talking to Mr. Torrance, if you don't mind my saying so. Perhaps a bit more.

I couldn’t agree with you more Delbert!

 

[Lava]

I have that same amp and have never had any distortion problems with either active or passive basses.
Is your gain knob on the amp fully engaged?
Is it your cab that is distorting?
Is the bass fully engaged on your amp?
Is the bass engaged on your basses?
These are some things that could cause distortion, aside from the amp having defects.

 

[juancaminos]

I had the same issues with the TT800. Turned off the High/Low gain switch (light out). It seems to do the opposite of what I thought. On your it would be the Active/Passive switch.

 

[Goatrope]

I’m following out of curiosity. D800 is my backup and I use it for tough load-ins, or when I just want not to be tweaking my amp. I play Thunderbirds and never once had that distortion experience, unless I really worked for it by running up the gain to max.

 

[Killing Floor]

Lower your pickups

 

[agedhorse]

Please follow my troubleshooting questions.

 

[Jack Torrance]

Please follow my troubleshooting questions.

Will do! I appreciate the quick response and will revisit troubleshooting when I get home. Although they just delivered my new to me Mesa PH115

 

[agedhorse]

Will do! I appreciate the quick response and will revisit troubleshooting when I get home. Although they just delivered my new to me Mesa PH115

Focus on the task at hand...

 

[JimmyM]

Focus on the task at hand...

Taskmaster Andy has spoken

But seriously Jack, he’s right. However, I would find a way to focus on both.

 

[JeezyMcNuggles]

I recently purchased a used Mesa d800 and am having a hell of a time getting anything but distortion/overdrive out of it. I am pretty new to bass playing and it took me a while to get my active basses to sound good, but man after I figured it out the Mesa sounds AMAZING! Anyway I have an Epiphone thunderbird and it sounds horrible. I can’t seem to find a good setting. Has anyone ever come across this situation? This bass has stock pups, while my P and J basses have active EMG’s. My previous amp was a GK mb200 which is pretty straightforward. Oh I am playing through a GK cx210 400 watt cab. Any comments are appreciated!

Turn the gain down