And on the Mark VII day they Boogied ...

[gearJunkie]

Mark IV mode on channel 3 loves the guitar's volume knob!

 

[gearJunkie]

Confirmation that the PS-2A squealing issue is related to running the H9 in 4 cable method with one side before the Mk7 and the other in the effects loop of the amp

Running the H9 only in the effects loop eliminates the annoying squeal without a need for an isolation transformer at the amp input

Hopefully the Helix floor in 4 cable method won't cause the squealing to return.

 

[gearJunkie]

So disappointing

Even with the isolation transformer inserted immediately in front of the Mk7 input, the PS-2A still squeals at about 6db lower than the processed guitar when combining with the Helix in 4CM.

Time to try the Ironman with this configuration. ...

 

[JTI]

Do you feel like the Fryette is not going to do what you want? I have heard of the transformer isolation issue on other forums but didn't have the issue when I had one?

 

[gearJunkie]

Do you feel like the Fryette is not going to do what you want? I have heard of the transformer isolation issue on other forums but didn't have the issue when I had one?

I'm not giving up on the PS just yet. My next endeavor is to unhook all my gear, both power and audio connections, and rewire to minimize possible sources for ground loops.

Right now everything is living in kind of a spaghetti matrix that is possibly the culprit. I'll know more tonight after I get some pay-the-bills work done.

 

[Whizzinby]

The most exotic setup I had with the PS was some sorta 7cm method deal with the QC, SYN2, PS100, w/ pedals in the loop. Never had any noise issues luckily.

I run the switches at Edge & Deep with the Fireball. Full mojo settings.

 

[gearJunkie]

The most exotic setup I had with the PS was some sorta 7cm method deal with the QC, SYN2, PS100, w/ pedals in the loop. Never had any noise issues luckily.

I run the switches at Edge & Deep with the Fireball. Full mojo settings.

That's good to hear. There still is hope for my rig.

I'll post back later tonight with my results.

 

[spawnofthesith]

Is 7cm actually a thing?


I always assumed people were joking around with that phrase

 

[gearJunkie]

Is 7cm actually a thing?


I always assumed people were joking around with that phrase

I believe it is when you have stereo effects both pre and post, requiring 3 more cables and a stereo effects loop.

Damn that's a lot of cables!

 

[gearJunkie]

Unplugged everything,

ran AC power cables from Helix, PS, and Mk7 to a single power strip,

plugged power strip into wall outlet,

ran speaker cables and amp out into PS,

ran 3 audio cables from helix to mk7 away from AC power cords and without looping them,

(NO isolation transformer) ,

plugged guitar into helix and powered everything on,

flipped standby switches,

hit a cord ....

Spoiler

SUCCESS!

 

[gearJunkie]

hit a cord ....

And that was with my Esquire style guitar with a single Seymour Duncan Antiquity pup

 

[gearJunkie]

Noticed that when bypassing the Mk7 preamp and using a Helix preamp, the resulting tone is dependent upon the configuration of the channel selected on the Mk7.

I verified this behavior by setting both channel 1 & 2 to fat mode and the Hx preamp sounded the same for both, but when configured for different modes, the output varies in both tone & volume

Now to ditch the boogie footswitch and get my MIDI on.

 

[gearJunkie]

I still get a little bit of funky noise when connecting Helix to laptop via USB, but that is not uncommon (double negative for emphasis ) in high gain configurations.

 

[gearJunkie]

Finally was able to get the Mk7 to play nice with the Hx using 4CM. Sounds great, feels great.

I documented the configuration and labeled the cables/connections, then tore it apart to experiment with a minimal pedal-centric rig

The H9 and ISP gate sit on top of the amp, and the AT Mod, an MC6, and expression pedal are on the floor.

MC6 controls the H9 and Mk7 channel switching, as well as toggling reverb, fx loop, and graphic eq.

Sounds great & feels great with a smaller footprint. But how long will that last before I "need" another pedal.

The experiment continues...

 

[GreatGreen]

Noticed that when bypassing the Mk7 preamp and using a Helix preamp, the resulting tone is dependent upon the configuration of the channel selected on the Mk7.

I verified this behavior by setting both channel 1 & 2 to fat mode and the Hx preamp sounded the same for both, but when configured for different modes, the output varies in both tone & volume

Now to ditch the boogie footswitch and get my MIDI on.

If I had to guess, I'd say this is because of the Presence knob on each channel which is controlling the behavior of the poweramp.

 

[gearJunkie]

If I had to guess, I'd say this is because of the Presence knob on each channel which is controlling the behavior of the poweramp.

Nope. Not the presence knob, or any of the channel knobs.

Verified behavior by cloning fat mode in channel 1 and channel 2 with exact same knob positions. Hx pre sounds the same through both.

Then switched channel 2 to crunch mode and the Hx preamp output volume dropped significantly. Change channel 1 from fat to crunch and heard the same shift in tone and attenuation.

 

[spawnofthesith]

So perhaps a similar issue I had to overcome on my Roadster....

I do a lot of live looping in my band and have an RC-500 last in my FX loop. A lot of our songs have layers of both clean and high gain loops on top of each other, and the issue I was running into was massive volume disparities on my loops once they were set and I changed channels. When I contacted Mesa Boogie the guy that called me said he had similar issues with his Mark VII and it was just one of the compromises of the way they do their loops. Now, on that note, I was able to solve this problem by running my cleans in 100 watt mode, and my high gain in 50 watt mode. No issues with the volume jumps/drops anymore.

Someone on the boogie board provided this more technical answer as to why that occurred:

You can change the presence controls to your hearts content, they are not connected to the actual presence of the feedback circuit. It is fixed. they are just high pass filters. The exception is the modern voice, that disconnects the fixed feedback circuit used for presence. The high pass filter part on the tone stack gets connected to ground. The presence control then gets connected as a tone control to the phase inverter at the same location the disconnected feedback circuit was injected. In other words, if you are not using the modern voice, there should be no major level shifting occurring on the phase inverter.

 

[gearJunkie]

So perhaps a similar issue I had to overcome on my Roadster....

I do a lot of live looping in my band and have an RC-500 last in my FX loop. A lot of our songs have layers of both clean and high gain loops on top of each other, and the issue I was running into was massive volume disparities on my loops once they were set and I changed channels. When I contacted Mesa Boogie the guy that called me said he had similar issues with his Mark VII and it was just one of the compromises of the way they do their loops. Now, on that note, I was able to solve this problem by running my cleans in 100 watt mode, and my high gain in 50 watt mode. No issues with the volume jumps/drops anymore.

Someone on the boogie board provided this more technical answer as to why that occurred:

Great information. Thank you for sharing. I have yet to play with channels configured for different power levels. A new variable is in play.

The experiment continues....

 

[gearJunkie]

Mesa/Boogie customer service finally called back...






In 6 to 8 weeks....,









an upgraded Mark VII headshell with the California Tweed treatment should arrive on my doorstep.

 

[JTI]