Mighty Motif Max - 12 September 2016 12:54 PM

Every DXR that I have used, whether with the Motif or other things, has produced a hiss. Is that from the DSP?

No, typically it is from improper gain staging.

The DXR has an extremely powerful amp, and is able to produce a lot of sound from even a weak signal feed.  This can lull one into not providing a strong enough signal to the DXR.

Since a low input signal will have a substantially reduced signal-to-noise ratio, the signal hiss will be magnified along with the weak signal itself.

The solution is to provide a strong, clean signal to the DXR amp.  I run my XF8, Hammond clonewheel, and P200 piano set to full output volume at each keyboard gain control.  These levels are then equaled and gain-staged at the mixer to provide an even, strong stereo feed to my DXR’s.  Each keyboard then has its own FC7 expression/volume pedal.

The amps can then produce a very strong level at a very reduced gain setting, without hiss.  I run my DXR’s at about 15 or 20% of maximum at their gain knobs, and at full FC7 pedal throw on my keyboards am able to produce huge volumes of clean, full-range sound (needless to say I rarely go there).

Is this true of any monitors as well? Whether passive or active? My church had issues with my previous keyboard “apparently” producing a ground-level hum and a loud hiss. When I used it with my own amps, there was no hiss whatsoever. This actually caused a huge problem, as the keyboard could not be heard through the monitors, only through the final amps, which were far away. Just curious!

-Max

cmayhle - 12 September 2016 03:23 PM

Mighty Motif Max - 12 September 2016 12:54 PM

Every DXR that I have used, whether with the Motif or other things, has produced a hiss. Is that from the DSP?

No, typically it is from improper gain staging.

Exactly. I’ve never had hiss but I don’t doubt I could produce some.

I use the balanced inputs fed from an Ultralite mk3 and have no noise. I also receive a monitor send from FOH to the MOTU. No noise. I respect the unbalanced/balanced cabling scheme and do not vary from it.
I mention this as I have a P90 unit here and can attest that it does not like TRS cabling and will protest loudly at their use. (The unit has unbalanced outputs, TS).

A while back the subject of hum came up and in trying to replicate the OP’s situation by using the unbalanced #2 input, I discovered a leakage in the power supply of one of my XS’s. This was unnoticed when used in my typical fashion thru a mixer fed into the balanced inputs. At the time I fed a variety of other equipment(unbalanced) thru the #2 input sans mixer and had no hiss. As noted by cmayhle, the speakers are very discriminating and will disclose any problems which may be fed into them. YMMV.

Stone

Mighty Motif Max - 12 September 2016 03:37 PM

Is this true of any monitors as well? Whether passive or active?....

Well, since it is the amp...and not the speakers themselves...that amplifies the sound (including hiss), it doesn’t really make sense to include passive monitors in the same discussion without addressing what is actually amplifying the sounds they project.

But yes, in theory any amp (active monitors for this discussion) will benefit in the same way through proper gain staging.  In practice, however, this is what often happens:

When adjusting the volume (what is actually heard) with lesser or under-powered units, it is much more common to “luck” into better gain-staging practice.  How?  Because in order to get “enough” sound out of lower-powered amps, raising the gain at earlier stages in the signal path is usually one of the first things attempted.

As stated in an earlier post, when using more powerful amps it is easier to get “lulled” into improper gain staging.  When a huge sound comes out of the unit during testing, one of the first actions taken is to turn down the instrument...at the instrument, unfortunately.  Why?  Because you look at the powerful monitor amp, and it is “only” on 6, so you think “well, I don’t need to turn it down, it’s not up that high”.  So instead, you turn down the gain on your synthesizer itself.

Yes, this brings the volume down to a listenable level, but it also produces a weaker signal...with more relative noise (hiss)...going to the amp.  The amp does not care how much noise there is in the signal, it will amplify all of it equally.

The solution is to keep the signal as strong as possible (without clipping or distortion, of course) throughout.  This maintains the highest signal-to-noise ratio, which is exactly what you want to feed to the amp.

Keep the signal strength up throughout the signal path gain staging, and let your powerful monitor amp (or main amp for that matter) loaf at just a fraction of its capabilities, for the least amount of noise in the final product.

Well, since it is the amp...and not the speakers themselves...that amplifies the sound (including hiss), it doesn’t really make sense to include passive monitors in the same discussion

Well, that question wasn’t really related. Just trying to solve two problems at once. :-)

So in other words, I should keep the keyboard’s volume slider/knob up pretty far, and have the sound people adjust the gain for the monitors? That would eliminate any hiss in the last described situation?

-Max

Mighty Motif Max - 12 September 2016 05:03 PM

...So in other words, I should keep the keyboard’s volume slider/knob up pretty far, and have the sound people adjust the gain for the monitors? That would eliminate any hiss in the last described situation?

-Max

Until now there hasn’t been any discussion of sound people (at least by me), only personal monitors that had keyboard(s) and other mics/instruments run into them.

If you bring FOH into the discussion, there are other dynamics that may introduce noise into the signal path.

Are you talking about your own keyboard signals going to the FOH board, and then being sent back to you, instead of going directly from your instruments into your monitors?

cmayhle - 12 September 2016 05:38 PM

Mighty Motif Max - 12 September 2016 05:03 PM

...So in other words, I should keep the keyboard’s volume slider/knob up pretty far, and have the sound people adjust the gain for the monitors? That would eliminate any hiss in the last described situation?

-Max

Until now there hasn’t been any discussion of sound people (at least by me), only personal monitors that had keyboard(s) and other mics/instruments run into them.

If you bring FOH into the discussion, there are other dynamics that may introduce noise into the signal path.

Are you talking about your own keyboard signals going to the FOH board, and then being sent back to you, instead of going directly from your instruments into your monitors?

This is when I am in a band. I will explain.

Keyboard is connected with a DI box to convert the 1/4” to XLR. From there the converted end is plugged into a multi-box(?), which has 21 inputs for XLR. That box has a cord running through the stage and then under the floor and through the walls until it reaches the sound booth, which has a very large mixer with 16 inputs at least. From there everything is output to two large speakers mounted on the ceiling, and also to some monitors, almost all of which are passive. The hiss is from the monitors, and was blamed on my keyboard’s output.

There also was a weird delay between the press of the keys and sound from the monitor. I found that the only way to stop the delay was to switch off all reverb and chorus from my keyboard, which flattened the sound to the point where I did not like it very much. This is an old problem with another keyboard, and I have not tried the Motif in this situation yet.

After this issue is covered, I would like to switch back to the original topic of this thread. Just trying to kill two birds with one stone, I guess. :-)

-Max

I agree with Mighty.  It could be a power ground loop issue, and if it is changing the board signal level isn’t going to fix it.  A good DI with a switch to lift ground will fix it, and is always a good thing to have in any gig bag.

My last gig I had noise buzz running straight to my PPA.  I added the DI, flipped the ground pad switch and it fixed it.  Voila.  I use a a Radial Pro D2, there are others.

Granted that ground hum is a separate issue from amplified circuit noise.  Unfortunately, this thread seems to have gone off on too many tangents to maintain much coherent discussion.

OK. I agree with cmayhle.

Back to my original question on what to do for stereo speakers for my Motif XF8:

I am looking to buy a second amp for my XF8, for live use. Up till now, I have just used either house equipment when live.

However, now I have a performance coming up in the next several weeks where there will be no equipment there. I only have the one amp, and would hate to perform solo piano in mono, even using the Mono Piano MW sound. My amp is a Yamaha MSR100.

So, here are my questions: 1. Keep the MSR100 and buy a second one?
2. Get two of a different amp and not use the MSR100 with my Motif?
3. Recommendations?
4. MSR100 + other amp?

My live setup usually consists of my XF8, a Shure SM-57 microphone, and a Titano Virtuoso Converter accordion, with a 1/4” output jack/internal mics. Sometimes I use the SM-57 as a vocal mic, sometimes as in instrumental mic. I play at a lot of different venues, with different setups. I play both indoor and outdoor gigs. I also play live on the street. Basically, I play primarily Ragtime and Relaxation solo on my XF, along with some contemporary Christian music.

From my flyer: “Max Thompson is a professional musician who can perform solo as well as accompany singers and dancers. He plays a wide variety of musical styles on piano, accordion, keyboard, and organ as listed:
World, Balkan, Italian, German, Russian, Polkas, Waltzes, Hymns, Contemporary Christian, ‘Oldies’ ( 1930’s and ’40’s), Classical, Ragtime, Relaxation, and Christmas Music.
He has performed at the following in the Midwest:

The Minnesota State Fair, The Festival Of Nations, NE Accordion Festival, Restaurants, Russian Cultural Center, Russian Soul: Ten Years In Minnesota, Maytag Dairy Farm’s Harvest Party, Community Care Food Distribution, Little Log House Pioneer Village and Antique Power Show four years in a row, Graduation Parties, Christmas Parties, Family Reunions, Funerals, Receptions, Nursing Homes, Senior Services, the Stillwater Reading Club, Lion’s Main (now Lion’s Tavern) restaurant, Birthday Parties, Hymn Sings, Community Outreach Events, and Church Services.
He also sings.
He Is Happy To Share His Music With You!”

I have not had much experience with other amps/brands.

What other brands do you recommend?

Thanks!

-Max

Anyone? Please?

-Max

How about the Stagepas 600i system? How do these stack up compared to a pair of DXR10s? Would I be able to use a good mixer with it, like a MG10XU?

Thanks!

-Max