It is currently Mon Mar 16, 2020 8:41 am

All times are UTC - 7 hours



Post new topic Reply to topic  [ 8 posts ] 
Author Message
Post subject: An experiment
Posted: Fri May 04, 2012 6:16 am
Offline
Aspiring Musician
Aspiring Musician

Joined: Wed Feb 16, 2011 7:24 am
Posts: 434
Next month, I'll be providing sound for a women's choir in a very live hall. It'll be a challenge, given the distance the mics have to be from the singers to take in all 30 of them without feeding back from the speakers.

They want mics for the choir (2), for soloists (2), and for a guitar, a piano, a bass and a percussionist. That's 8 XLR inputs. I have a Fender Passport 500 Pro and a Passport 300 Pro. The 500 has six XLR inputs and two 1/4" TS inputs. There are a couple ways I could handle this.

I could borrow a pre-amp to run a couple of mics through the 1/4" inputs for channels 6 and 7 on the 500. Then, I'll have to forfeit the use of the Passport's controls for those inputs. I really like those controls. For the dress rehearsal, I'll bring along the borrowed pre-amp in case my other experiment doesn't work.

I think I want to run the choir and soloists through the Passport 300, then run the Stereo Out from that into one of the stereo channels on the 500 (even though it's all mono), and run all the accompaniment through the 500. I'd then either place the 300 speakers in the center with the 500 speakers on the outside so that the accompaniment will sound like it is off to the sides while the singers are all central, or I could place the singers' speakers on the left where they will be, and the accompanists' speakers on the right where they will be.

All speakers will be aimed at the most distant (from that speaker) corner of the room to discourage feedback. Live halls I've done this for in the past have worked well with this technique, since it avoids sound waves going straight to the back wall, bouncing off in a coordinated wave back to the mics. Alternatively, I might aim them at the nearest diagonal corner, if the treble distribution doesn't cover the front corners of the audience the other way.

Besides letting me use the Passports' controls over the channels, this will make the sound match the focus of the event. The singers are the focus and will be coming out of all four speakers. The accompanists will be off to a side, though experience tells me that people will not notice any of this and will think all the sound is coming out of all the speakers.

With the live hall, I expect the volume level to be relatively low. The hall doesn't need much amplification, and there's no way to stop higher volumes from feeding back, given the mic placement. I'll put the speakers out in the hall, off the stage, and I'll put two monitors off the stage at a distance from all the performers, just to give them some treble clarity amid the reverberations of a sound system pointed away from them.

I have three Mackey SRM 150s. I intend to put one near me at the sound board, patched into the Stereo Out from the Passport 500 (1/8" TRS to a the pair of RCA inputs on the SRM), and daisy chain with XLR to the two other SRMs. I intend to bring along an iPod to play while I walk the hall to decide the overall volume level, then check the LEDs for a sense of how loud it should be, then during the performance I should be able to use the monitor to adjust the balance, while watching the LEDs to keep the overall volume level near what I chose while standing out in the hall.

This is to compensate for not having a snake. I have enough other expenses for this gig without buying a snake, and enough other technical challenges without adding that level of complexity to the mix.

We'll see how it goes.


Top
Profile
Fender Play Winter Sale 2020
Post subject: Re: An experiment
Posted: Fri Jun 01, 2012 6:11 am
Offline
Aspiring Musician
Aspiring Musician

Joined: Wed Feb 16, 2011 7:24 am
Posts: 434
Not to assume that too many people are interested, but...

The dress rehearsal was educational. As compact as this system is, I have issues with speaker placement. The hall is very live and feedback prone. The room has a mid-frequency tone that it likes too much and the air conditioning system plays that note. Whenever the choir sings or the piano plays near that note, feedback howls, unless the mics are turned very low.

The odd part is that while the mic channels have a specific point above which they cannot be turned (about 9:00, or something like 3 out of 10), I can do this with the master volume up 1/2 -- find the feedback point and back off slightly -- and then I can crank the master volume up full and it doesn't feed back. It's like the feedback threshold has everything to do with the channel level and nothing to do with the master volume. Very weird.

Anyway, placing speakers at the corners of the stage was a total failure. Feedback at any volume.

There's really only one place on each side that I can put the speakers at the sides of the hall. It's a church and the aisles at the sides are too narrow for a speaker stand farther back. So, my four-speaker trick isn't working.

Add that the percussion and bass need no amplification at all. Even the guitar sounds better balanced when it is picked up by the choir mics. I mic the piano and the choir. Five inputs total. So, I'm considering only bringing the 500 pro and leaving the 300 pro at home.

The setting would be fine without amplification at all. The acoustics of the hall are so live, and the mics have to be so far away from the choir in order to pick up all the singers that you have to get near the speakers to hear them louder than the choir itself.

As it turns out, the main service I'm doing for them is recording them. They seem to cherish that, despite it being mono and low volume. This is basically the most challenging setting I've had yet for the system.

I've tried pulling down the high EQ, then the low EQ, then cranking both up and turning down the overall volume. I can't make it louder without feeding back. Maybe if I had a notch filter to play with, I could do better, or some kind of frequency analyzer to find the feedback frequency.

Anyway, it makes me glad that most halls are not this reverberating and that most sound sources can be much closer to the microphones.


Top
Profile
Post subject: Re: An experiment
Posted: Mon Jun 18, 2012 7:11 am
Offline
Aspiring Musician
Aspiring Musician

Joined: Wed Feb 16, 2011 7:24 am
Posts: 434
Just to beat the dead horse, as it turned out, they didn't need as many channels as they led me to believe, so I ran everything through the Passport 500 Pro. I didn't use the 300 at all because the hall didn't have room for a second set of speakers in the outer aisles, and placing speakers anywhere near the stage caused feedback no matter what I did.

I kept the master volume very low (to prevent feedback -- the EQ controls on the Passport were not adequate for me to notch filter the specific frequency that the room enhanced entirely too much, especially since the air conditioner, which the choir refused to consider turning off, played that same note, making the room constantly ready to shriek every time the choir got near that note). Since they wanted a recording, I kept the individual channel levels high so that the mics, that had to be distant enough to pick up 30 people singing, would make a recording that people could actually hear, but when they all stomped on the stage in unison in one song, or pounded on an incredibly loud drum on another one, or whenever the crowd whooped, it was impossible to cut back on all individual channels levels at once fast enough to prevent the horrid clicking sound of digital clipping. Audacity couldn't really clean that up all that well.

The choir was happier with the result than I was. I'll give another post about making the next step in pimping up my sound system.


Top
Profile
Post subject: Re: An experiment
Posted: Fri Sep 21, 2012 11:19 am
Offline
Hobbyist
Hobbyist

Joined: Thu Sep 20, 2012 4:31 pm
Posts: 3
First post.

I've read quite a few of your posts as I await delivery of my new passport 500 pro and just wanted to thank you for various detailed posts.

I have been lugging around two Acoustasonic DSP 30s for a few years now, bi-amping them to provide the dispersion I wanted. After years of playing six nights a week (background solo nylon player in restaurants) you'd think I would have made the move a little sooner, but I was particularly concerned with the depth of my sound.

After recently playing a gig where the house system was a 250, I realized my fears were not grounded in reality. With only the most minor adjustments I as able to get the sound right where I wanted with depth and clarity. I am presuming the 500 will easily be up to the job.

So I am eagerly awaiting for delivery.

I am particularly interested in the USB recording function. It doesn't seem particularly daunting to format the drive, but my question is, is formatting necessary? And is there a brand of USB drive that is optimum?


Top
Profile
Post subject: Re: An experiment
Posted: Sat Sep 22, 2012 4:26 pm
Offline
Aspiring Musician
Aspiring Musician

Joined: Wed Feb 16, 2011 7:24 am
Posts: 434
The brand of USB FLASH drive doesn't matter, but you do want to watch out for certain features. Some drives are designed to be used by MS Windows only with special security features built in. They have an auto-load program that automatically launches without your knowledge or consent and asks you for a password. If you get the right password, it gives you access to the drive. Without the password, everything on the drive is encrypted garbage. The password decrypts it.

This kind of FLASH drive requires MS Windows to work. The Passport doesn't use MS Windows and expects the drive to, well, just be a drive. The Passport cant load or execute the autoload encryptor/Decrypter. So, if you can reformat that drive on the passport or on a Mac, it should work fine. Some can't be reformatted and simply won't work with the Passport.

So, any plain drive should work. I've used 4GB and 64GB drives. They all work fine for me. The two file systems that work are FAT and ExFAT. FAT stands for "File Allocation Table". It's the technical name for the kind of file system used by UNIX and DOS.

Macs, Windows and Unix can all use FAT.

For larger drives, FAT doesn't work. I lacks sufficient capacity for a 64GB drive, for instance. So, they invented ExFAT. It's similar to FAT in design, but handles larger drives. It was invented specifically for USB FLASH drives.


Top
Profile
Post subject: Re: An experiment
Posted: Sun Sep 23, 2012 3:51 pm
Offline
Hobbyist
Hobbyist

Joined: Thu Sep 20, 2012 4:31 pm
Posts: 3
Thanks. I'm looking forward to it.


Top
Profile
Post subject: Re: An experiment
Posted: Mon Oct 08, 2012 2:21 pm
Offline
Hobbyist
Hobbyist

Joined: Thu Sep 20, 2012 4:31 pm
Posts: 3
Update. I've been working with my new Passport 500 pro for ten days now and I am completely satisfied with the system. It is a simple, straightforward machine. USB Recording worked as advertised and just a breeze to work with back on my laptop.

The season will be starting where I live in about three weeks so I'll start to gig with it six nights a week and see how it holds up.


Top
Profile
Post subject: Re: An experiment
Posted: Thu Oct 18, 2012 12:18 am
Offline
Hobbyist
Hobbyist

Joined: Wed Oct 17, 2012 11:26 pm
Posts: 2
There are a good way for getting styles that is applied in having it more designs to create a perfect interest to acknowledge ways.


Top
Profile
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 8 posts ] 

All times are UTC - 7 hours

Fender Play Winter Sale 2020

Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to: