Reamping Woes.. with Passive DI.

[samth3mancgp]

Man.. I'm sorry that I have to post yet another reamping thread.. but I have been having trouble removing a constant hum from my signal when reamping. I have read a ton of threads from this site and elsewhere and I have seen plenty of arguments to why you should get a dedicated reamp box, and other arguments that say they are a waste of cash and you can plug in straight from your interface. (both with electronic engineering mumbo jumbo to back it up that makes only a bit of sense to me). Basically I have been left with more questions than answers. Here is how I am running my setup:

I am currently using a passive DI box before the amp, and I have worked with this setup several other times before. The tones have been coming out out pretty good but I just realized last night how much more hiss/noise/hum (or whatever) I am getting with this setup as opposed to plugging into a normal guitar. The hiss is present whether I am "playing" signal to the amp or not. I tried 2 different amps, Peavey 6505+ and a Mesa Dual rec head. Similar results from both. I have tried different cables, different DI boxes, different inputs/outputs, different power outlets (we have power conditioners, and orange colored outlets that are "clean" power for audio gear.)

The system I am using is 24inx24out ProTools HD2, signals routed through a TT patchbay, amp head sits in the control room with me and the only long cable run is the speaker cable to either the iso booth or the live room (either 12 or 10 guage). I was going to go back tonight to try other configurations, but the AC system is out right now and the CR sits at a nice and toasty 90 degrees

The only thing I haven't tried it direct from the converter (192I/O) and using a dedicated reamp box (since I don't have one). I could rent one from Gear For Days, or Blackbird rentals here in Nashville to see if that fixed the problem. I know Gear For Days has the Millennia TD-1 for rental there.

Anybody else with this crazy hiss/hum problem?

 

[Trevoire520]

Have you tried using the ground lift on the DI?

 

[Derykus]

Are you using a laptop? I am, and I have to unplug mine to get usable re-amp results. If I don't unplug/run on battery power, my reamps have an unbearable noise in them - regardless of a guitar signal or not. It's most likely a ground loop. If you have a laptop, try unplugging. If you have a desktop - I don't know what to tell you! It's not the reamp box or your DI's, it's probably your computer power supply wreaking havoc on your setup.

 

[samth3mancgp]

Thanks for the replies guys!

I have tried the ground lift on two different passive DIs with no change. Even though the system we run is ProTools HD and uses a Mac Pro in a separate machine room (that I think also has it's own separate circuit) I DID have my Macbook Pro plugged in charging in an outlet close to the one the amps were plugged into!!

Man, if that was the source of my problem... hahahaha I will have wasted hours trying to isolate the problem and even more reading up on how to fix it. All that reading did get me wondering about the many different methods that people use to reamp, whether it be a dedicated box, straight from interface, passive DI, or buffered through a pedal. I could try all of those except for the dedicated box. Are you guys using something like the Redeye, Pro RMP, or Reamp?

I can't wait to see if that was the issue now. The AC gets fixed in a few days, not sure if I want to brave the burning hot control room til then

Thanks again.

 

[Red Phoenix]

Before using my Redeye i got noise on higher frequencys when my laptop was plugged.on battery i had no noise..(its because of the ground connection of the schuko plug). The redeye fixed that problem for me but i still got 50/60hz hum..i fixed that with changing powerplug positions or rotating it 180°

 

[jaketackett93]

Trevoire520, Have you covered in another thread how you personal reamp? Because i have heard your stuff and i like it alot. I have a TH30 and your reamps of yours help me make my choice to buy mine. Do you use a reverse di?

 

[samth3mancgp]

I am back at the studio today and trying reamping again..

Unfortunately I found out that my laptop was not my problem. The hiss is still there and is still way more than the hiss with a a guitar plugged in (almost none). Still trying to figure out what is going on. I have attached a file with a bit of reamped guitar as an example of my problem, so you all can hear what I am hearing. Is that a ground loop? Or something else?

 

[Red Phoenix]

Sounds like the normal background noise i get but way louder than normal. Could be caused by an impedance missmatch..anyway theres no (noticeable) ground hum and no strange noises coming from laptop power plug (these sounds completely different)
you really should try to get a proper reamp box or try another interface or less components between interface and amp...leave out the patchbay for a test

 

[samth3mancgp]

Will something as cheap and simple as the ProRMP solve the issue? I just bought my 6505+ last week and still owe my friend half the money for it. I'd love to have a real reamp box to try right now.. I am about to try going straight from the 192I/O output to the amp using a TT to 1/4" unbalanced cable.

It's pretty damn difficult to get signal anywhere without the patchbay in the equation. Maybe I'll try bringing the entire setup to our Studio B that doesn't have a patchbay and is completely separate from this rig.. I definitely want to get this figured out, whether it means gettinga reamp box or not.

 

[egan.]

Try a ground lift a/c plug on the amp.

 

[samth3mancgp]

Sounds like the normal background noise i get but way louder than normal. Could be caused by an impedance missmatch..anyway theres no (noticeable) ground hum and no strange noises coming from laptop power plug (these sounds completely different)
you really should try to get a proper reamp box or try another interface or less components between interface and amp...leave out the patchbay for a test

So the background noise never really goes away? The amount of noise with my Les Paul Studio plugged in is almost nothing compared to this weird white noise coming in when reamping. Does the amp never truly react to a reamping signal the same way as the guitar itself? I guess it makes sense because of the extra chain the guitar had to go through (DI box, preamp, A/D, D/A, more cables, another DI box/reamp box.) Perhaps I am looking for perfection that just isn't possible.

So anyway, I did a quick test using a different cab/mic/shorter cables using my laptop (not plugged into it's charger) and an Mbox 2 pro. The reason I didn't use the same cab/mics was.. laziness? I didn't want to carry the Mesa Rectifier cab up the stairs from the live room. So This example is with a Marshall Cab, and a Sennheiser e609.



Here is a picture of the clips in ProTools, (note the numbers on the left that show the PEAK level of the hiss between the two clips that I matched fairly close in level.) Something around 6dB difference between the two? I wonder if that could have been the cab's doing? I should probably do a better test where the only variable that changes is the recording rig (HD system with patchbay vs. unplugged laptop with single cables coming form Mbox 2 Pro.

Try a ground lift a/c plug on the amp.

The 6505 has a "+ - and 0" switch on the back near the power cord. I messed with it and it caused no change in the reamp hiss.

Lastly, which reamp boxes are you all using? The ProRMP is definitely the cheapest option, but if there is something that will help the noise floor more then maybe I should just get that ASAP..

Thanks,
-Sam

 

[Derykus]

I use the Radial JCR Reamp, and I've also used straight out of my RME Babyface - and I don't get white noise like that. Are you running the level too hot into the amp? That's what it sounds like to me.

 

[Red Phoenix]

>> The hiss is present whether I am "playing" signal to the amp or not. <<

So i guess it's not the DI and should not be the problem of a too hot signal.

Another point which comes to my mind is a fault i did when starting reamping. The output of my Interface was a balanced output (stereo jack needed / TRS connector) and the input from the amp is mono so the half of the signal would get lost when just using a unbalanced cable (TS connector). reamping boxes have balanced inputs (from interface) and unbalanced outputs (to amp) so no level gets lost here.

 

[samth3mancgp]

>> The hiss is present whether I am "playing" signal to the amp or not. <<

So i guess it's not the DI and should not be the problem of a too hot signal.

Another point which comes to my mind is a fault i did when starting reamping. The output of my Interface was a balanced output (stereo jack needed / TRS connector) and the input from the amp is mono so the half of the signal would get lost when just using a unbalanced cable (TS connector). reamping boxes have balanced inputs (from interface) and unbalanced outputs (to amp) so no level gets lost here.

Indeed I don't think that the problem has anything to do with how hot the signal is coming out of the DAW. The amount of hiss stays exactly the same even when I mess with the fader in the DAW. I tried going straight out of the patchbay into the amp as well using a TT to 1/4" cable that was in the machine room. They were RIDICULOUSLY noisy, like the hiss also had a hum and it was louder than the actual guitar signal. Some of them didn't even pass signal at all.

The passive DI yields the best result for sure.. but it's still not good enough. Man this is horrible..

 

[samth3mancgp]

I thought I would conclude this thread by posting up clips of Passive DI Box vs. a Radial ProRMP that I picked up. The results were astounding to say the least. I tried it all in my efforts to isolate and rid this hiss/noise guys.. Passive DI, direct from interface to amp, using a native rig with an Mbox (so I could avoid running through the patchbay) switching out cables, trying 3 different passive DI's, etc etc..

Basically the reamp box had 20+ dB less noise for reasons unknown. My friend who was having similar problems had the same result by simply getting a proper Reamping box (also ProRMP). Anybody on the fence about whether or not a reamp box is necessary should listen to these clips because the result speaks for itself. I am working in a real pro studio, not my parents basement. The reamp box is working some kind of magic on the noise that makes it worth far more than I paid for it.. My 6505+ going into Mesa Rectifier cab with the reamp box is quiter than having an actual guitar plugged in now!! (at least with my Gibson Les Paul Studio).

[SOUNDCLOUD]http://soundcloud.com/samth3mancgp/sets/test-with-reamp[/SOUNDCLOUD]

^ click on the link to listen to both clips? I guess it doesn't show both here in the forum.

I know this is just my experience, and others may have drastically different situations. YMMV. Hopefully this thread will be useful for other people that have similar problems as me.

-Sam

 

[Derykus]

Hahahaha, all of my responses were under the false assumption that you were using a passive reamp box, not a passive DI. Guess I should read more carefully! No wonder you were having issues.

Why did you put a DI in between your amp and output? Were you running it in reverse?

 

[samth3mancgp]

Hahahaha, all of my responses were under the false assumption that you were using a passive reamp box, not a passive DI. Guess I should read more carefully! No wonder you were having issues.

Why did you put a DI in between your amp and output? Were you running it in reverse?

Yes and yes! Hey, my friend said that it always worked for him, and other's have too. The noise just hit me the other day and I decided to go on the quest for a solution.

 

[Virgil.]

The only time I ever got a nasty hum or ground loop was when I was reamping using my DI box backwards; however, once I started using an actual reamp box (Radial ProRMP) that solved all the noise issues for me.

 

[Fox Mulder]

The reamp box is working some kind of magic on the noise that makes it worth far more than I paid for it.. My 6505+ going into Mesa Rectifier cab with the reamp box is quiter than having an actual guitar plugged in now!! (at least with my Gibson Les Paul Studio).

AFAIK, reamp boxes have 1:1 isolation transformers in them

 

[Eduardo Apolonia]

From my experience, that sounds like the typical scenario of injecting a sound too weak on the reamp box and compensating the volume on the reamp box.

What is the peak volume of the DI Wavs?

If you inject the DI sound in a "normal volume" analog level (+4dBU) it's too weak for the reamp boxes. I find that an average good level for a DI to a reamp box is about +15dBU.
It contradicts what is known as an "ideal" analog level, and I don't understand why it works like that, it makes my converters run too hot in my opinion.

Wait a minute, you weren't using a reamp box?
If not, you would have a impedance mismatch, and that would cause the noise.

You can read about reamping FAQs here:
http://www.reamp.com/faq.html