Sign in with
Sign up | Sign in
Your question

Power amp for church PA

Last response: in Home Audio
Share
June 15, 2005 12:52:55 PM

Archived from groups: rec.audio.pro (More info?)

Hi all,
I'm in the middle of the slow process of upgrading the church sound
system. I started the project by installing two Shure MX418 podium mics
and a Behringer UB1832 mixer. A decent power amp is next on my list. My
primary concern is reliability (i.e. no bursting into flames and burning
down the building!). I'm sure just about every power amp out there is
'ok' vis-a-vis sound quality at the levels we would be using. The
current speakers are Cambridge Soundworks installed on the walls
(aesthetics trumped sound when those were installed) and they may be
replaced in the future as well. Models I have looked at include the QSC
PLX1602, Crown CE1000, and the Behringer EP1500. Is there some 'net
resource that has distilled some of the reliability info for this stuff?
Sort of like a 'Consumer Reports' if you will. Other than that, any
personal experience you might have would be appreciated.

thanks
bill pittore

bp-x47 AT pobox.com

More about : power amp church

Anonymous
June 15, 2005 1:07:40 PM

Archived from groups: rec.audio.pro (More info?)

bill wrote:
> Hi all,
> I'm in the middle of the slow process of upgrading the church sound
> system. I started the project by installing two Shure MX418 podium mics
> and a Behringer UB1832 mixer. A decent power amp is next on my list. My
> primary concern is reliability (i.e. no bursting into flames and burning
> down the building!). I'm sure just about every power amp out there is
> 'ok' vis-a-vis sound quality at the levels we would be using. The
> current speakers are Cambridge Soundworks installed on the walls
> (aesthetics trumped sound when those were installed) and they may be
> replaced in the future as well. Models I have looked at include the QSC
> PLX1602, Crown CE1000, and the Behringer EP1500. Is there some 'net
> resource that has distilled some of the reliability info for this stuff?
> Sort of like a 'Consumer Reports' if you will. Other than that, any
> personal experience you might have would be appreciated.
>
> thanks
> bill pittore
>
> bp-x47 AT pobox.com

Consider Carvin. I've had a DCM150 running continuously for over eight months now and it is still
just happy as a clam. No flames, sparks or other indications of burning.

And in a PA system I just tested, we were using DCM 1000's and cranked it up to over 80db and it was
pristine clean sounding.

--fletch
Anonymous
June 15, 2005 1:21:12 PM

Archived from groups: rec.audio.pro (More info?)

In article <mKWdnV2omZs6uS3fRVn-2A@rcn.net>, bill <bp-x47@poboxDOTcom> wrote:
> I'm in the middle of the slow process of upgrading the church sound
>system. I started the project by installing two Shure MX418 podium mics
>and a Behringer UB1832 mixer. A decent power amp is next on my list. My
>primary concern is reliability (i.e. no bursting into flames and burning
>down the building!). I'm sure just about every power amp out there is
>'ok' vis-a-vis sound quality at the levels we would be using. The
>current speakers are Cambridge Soundworks installed on the walls
>(aesthetics trumped sound when those were installed) and they may be
>replaced in the future as well. Models I have looked at include the QSC
>PLX1602, Crown CE1000, and the Behringer EP1500. Is there some 'net
>resource that has distilled some of the reliability info for this stuff?
> Sort of like a 'Consumer Reports' if you will. Other than that, any
>personal experience you might have would be appreciated.

Look at the QSC RMX series of amplifiers. I have been really impressed
with the reliability of the things.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."
Related resources
Anonymous
June 15, 2005 2:17:43 PM

Archived from groups: rec.audio.pro (More info?)

bill wrote:
> Hi all,
> I'm in the middle of the slow process of upgrading the
church sound
> system. I started the project by installing two Shure
MX418 podium mics

Do you think your podum mics sound natural? What are your
podiums like?

> and a Behringer UB1832 mixer.

Life is sweet when things are that simple. ;-)


> A decent power amp is next on my
> list. My primary concern is reliability (i.e. no bursting
into flames
> and burning down the building!). I'm sure just about
every power amp
> out there is 'ok' vis-a-vis sound quality at the levels we
would be
> using. The current speakers are Cambridge Soundworks
installed on
> the walls (aesthetics trumped sound when those were
installed) and
> they may be replaced in the future as well.

To say the least.


Frankly, any serious SR amp will probably be easily capable
of making most home audio speakers burst into flame or at
least emit a bit of smoke.

>Models I have looked at
> include the QSC PLX1602, Crown CE1000, and the Behringer
EP1500.

IMO the QSC RMX series of amps would be more competitive
with the other amps you've mentioned.

> Is there some 'net resource that has distilled some of
the reliability
> info for this stuff? Sort of like a 'Consumer Reports'
if you will.

QSC has an long enviable record for reliability, as does
Crown. Behringer would be in the "most improved, over the
past several years" category. They are all, IME decent.
June 15, 2005 2:47:09 PM

Archived from groups: rec.audio.pro (More info?)

Arny Krueger wrote:

>bill wrote:
>
>
>>Hi all,
>> I'm in the middle of the slow process of upgrading the
>>
>>
>church sound
>
>
>>system. I started the project by installing two Shure
>>
>>
>MX418 podium mics
>
>Do you think your podum mics sound natural? What are your
>podiums like?
>
>
I like the new mics quite a bit as do the other members. They seem to
have a bit of a peak in the high end which can make some speakers sound
rather sibilant; a little EQ tweak on the mixer keeps that in check.
The mics have the hypercardiod cartridge installed. We have one podium
and the mics are mounted about one foot off center (L to R) and about
15" forward of the speaker, which places the business end about 8 - 10"
from the person's mouth.
Given the current limitations of the rest of the system, just adding
these mics and the new mixer
improved the sound from nearly unintelligible to rather pleasant. The
room is a big echo chamber essentially, 60' x 40' x 30' plaster walls,
hardwood floor, tin ceiling.

>
>
>>and a Behringer UB1832 mixer.
>>
>>
>
>Life is sweet when things are that simple. ;-)
>
>
>
>
>>A decent power amp is next on my
>>list. My primary concern is reliability (i.e. no bursting
>>
>>
>into flames
>
>
>>and burning down the building!). I'm sure just about
>>
>>
>every power amp
>
>
>>out there is 'ok' vis-a-vis sound quality at the levels we
>>
>>
>would be
>
>
>>using. The current speakers are Cambridge Soundworks
>>
>>
>installed on
>
>
>>the walls (aesthetics trumped sound when those were
>>
>>
>installed) and
>
>
>>they may be replaced in the future as well.
>>
>>
>
>To say the least.
>
>
>Frankly, any serious SR amp will probably be easily capable
>of making most home audio speakers burst into flame or at
>least emit a bit of smoke.
>
>
Maybe that's a good thing; unplanned speaker upgrade! ;-)

>
>
>>Models I have looked at
>>include the QSC PLX1602, Crown CE1000, and the Behringer
>>
>>
>EP1500.
>
>IMO the QSC RMX series of amps would be more competitive
>with the other amps you've mentioned.
>
>
>
>>Is there some 'net resource that has distilled some of
>>
>>
>the reliability
>
>
>> info for this stuff? Sort of like a 'Consumer Reports'
>>
>>
>if you will.
>
>QSC has an long enviable record for reliability, as does
>Crown. Behringer would be in the "most improved, over the
>past several years" category. They are all, IME decent.
>
>
Thanks for the info!

bill

>
>
>
>
>
Anonymous
June 15, 2005 7:54:38 PM

Archived from groups: rec.audio.pro (More info?)

"bill" <bp-x47@poboxDOTcom> wrote in message
news:1cWdna-Fzs_woi3fRVn-pQ@rcn.net...

> >Do you think your podum mics sound natural? What are your
> >podiums like?
> >
> I like the new mics quite a bit as do the other members. They seem to
> have a bit of a peak in the high end which can make some speakers sound
> rather sibilant; a little EQ tweak on the mixer keeps that in check.
> The mics have the hypercardiod cartridge installed. We have one podium
> and the mics are mounted about one foot off center (L to R) and about
> 15" forward of the speaker, which places the business end about 8 - 10"
> from the person's mouth.

That's a classic setup for comb filtering unless the preacher remains
perfectly centered. Try, temporarily, mounting a single microphone dead
center on the podium (maybe use a mic stand so you don't mess up the
podium). I think you'll find that the timbre of the voice is much better.

Then you get to deal with the problem of preachers who sway side to side.
Mounting the two mics in the center, capsules stacked, each pointing 45
degrees to one side, ought to take care of that. With hypercardioids that
equates to a single plain cardioid for combined pickup pattern.

Peace,
Paul
Anonymous
June 15, 2005 7:54:39 PM

Archived from groups: rec.audio.pro (More info?)

I also recommend the single mic dead center as stated. Then look at
making your next purchase (after the amp) a wireless lavaliere for the
minister. Then when the minister speaks just turn the podium mic off.

Paul Stamler wrote:

>That's a classic setup for comb filtering unless the preacher remains
>
>perfectly centered. Try, temporarily, mounting a single microphone dead
>center on the podium (maybe use a mic stand so you don't mess up the
>podium). I think you'll find that the timbre of the voice is much better.
>
>Then you get to deal with the problem of preachers who sway side to side.
>Mounting the two mics in the center, capsules stacked, each pointing 45
>degrees to one side, ought to take care of that. With hypercardioids that
>equates to a single plain cardioid for combined pickup pattern.
>
>
Anonymous
June 15, 2005 7:54:39 PM

Archived from groups: rec.audio.pro (More info?)

Paul Stamler wrote:
> "bill" <bp-x47@poboxDOTcom> wrote in message
> news:1cWdna-Fzs_woi3fRVn-pQ@rcn.net...
>
>>> Do you think your podum mics sound natural? What are
your
>>> podiums like?
>>>
>> I like the new mics quite a bit as do the other members.
They seem
>> to have a bit of a peak in the high end which can make
some speakers
>> sound rather sibilant; a little EQ tweak on the mixer
keeps that in
>> check. The mics have the hypercardiod cartridge
installed. We have
>> one podium and the mics are mounted about one foot off
center (L to
>> R) and about 15" forward of the speaker, which places the
business
>> end about 8 - 10" from the person's mouth.

> That's a classic setup for comb filtering unless the
preacher remains
> perfectly centered.

Not likely, either in terms of location or in terms of
theology. ;-)


> Try, temporarily, mounting a single microphone
> dead center on the podium (maybe use a mic stand so you
don't mess up
> the podium). I think you'll find that the timbre of the
voice is much
> better.

Still plenty of opportunities for resonances and comb
filtering based on reflections from the various flat
surfaces in a typical podium. I designed our podium to have
a large tray so that both a laptop and sermon notes could be
acommodated. I also designed the vertical support in the
shape of a cross, given that we are an evengelical church.
This resulted in a very practical working tool for the
person speaking, but colors the sound lots.

Acoustics wasn't in my mind at all when I designed the
pulpet. What was I thinking? Lots of reflections and an
over-all boxy sound resulted, as noted with several
different cardioid podium mics.

I mitigated much of this with a hypercardioid (Audix OM-3)
mic.

I plan to shortly cover all the flat surfaces that face the
mic with 2" acoustic foam.


> Then you get to deal with the problem of preachers who
sway side to
> side. Mounting the two mics in the center, capsules
stacked, each
> pointing 45 degrees to one side, ought to take care of
that. With
> hypercardioids that equates to a single plain cardioid for
combined
> pickup pattern.

Kinda-sorta. The resulting pattern has the width indicated.
However its still hypercardiod-narrow in the vertical
direction. This may be good news when it comes to rejecting
loudspeakers that are overhead or on the floor. When the
speakers are to the left and right, you probably loose much
of the feedback-prevention benefits of hypercardioids.
Anonymous
June 15, 2005 8:42:45 PM

Archived from groups: rec.audio.pro (More info?)

>other indications of burning.
>

IOW, smellable indicators?

-John O
Anonymous
June 15, 2005 10:26:19 PM

Archived from groups: rec.audio.pro (More info?)

"Arny Krueger" <arnyk@hotpop.com> wrote in message
news:r4idnZjfm_2D9i3fRVn-iQ@comcast.com...

> > Then you get to deal with the problem of preachers who
> sway side to
> > side. Mounting the two mics in the center, capsules
> stacked, each
> > pointing 45 degrees to one side, ought to take care of
> that. With
> > hypercardioids that equates to a single plain cardioid for
> combined
> > pickup pattern.
>
> Kinda-sorta. The resulting pattern has the width indicated.
> However its still hypercardiod-narrow in the vertical
> direction. This may be good news when it comes to rejecting
> loudspeakers that are overhead or on the floor. When the
> speakers are to the left and right, you probably loose much
> of the feedback-prevention benefits of hypercardioids.

Right, but at least you're no worse off than with a cardioid. I agree,
though, that a wireless clip-on is the best answer. Of course, then they
want to walk into the congregation...

Peace,
Paul
June 16, 2005 12:49:23 AM

Archived from groups: rec.audio.pro (More info?)

Paul Stamler wrote:
> "bill" <bp-x47@poboxDOTcom> wrote in message
> news:1cWdna-Fzs_woi3fRVn-pQ@rcn.net...
>
>
>>>Do you think your podum mics sound natural? What are your
>>>podiums like?
>>>
>>
>>I like the new mics quite a bit as do the other members. They seem to
>>have a bit of a peak in the high end which can make some speakers sound
>>rather sibilant; a little EQ tweak on the mixer keeps that in check.
>>The mics have the hypercardiod cartridge installed. We have one podium
>>and the mics are mounted about one foot off center (L to R) and about
>>15" forward of the speaker, which places the business end about 8 - 10"
>>from the person's mouth.
>
>
> That's a classic setup for comb filtering unless the preacher remains
> perfectly centered. Try, temporarily, mounting a single microphone dead
> center on the podium (maybe use a mic stand so you don't mess up the
> podium). I think you'll find that the timbre of the voice is much better.
>
> Then you get to deal with the problem of preachers who sway side to side.
> Mounting the two mics in the center, capsules stacked, each pointing 45
> degrees to one side, ought to take care of that. With hypercardioids that
> equates to a single plain cardioid for combined pickup pattern.
>
Thanks for the proper terminology. I was afraid of 'phasing' effects
when I put it in. After googling for info on comb filter effect I'm
pretty sure that's what I hear occasionaly. I didn't cut any holes in
the podium yet, the units are mounted to wooden blocks which are held in
place by double-sided tape. I may try some experiments as you mention.
I might also invest in a different cartridge to see how an omni or
cardiod would work.
While we do use a wireless lavaliere at times, the minister is just not
comfortable with it. Not sure why; so we need to have the podium mics.

> Peace,
> Paul
>
Thanks,
bill
>
Anonymous
June 16, 2005 6:07:33 AM

Archived from groups: rec.audio.pro (More info?)

bill wrote:
> Thanks for the proper terminology. I was afraid of 'phasing' effects
> when I put it in. After googling for info on comb filter effect I'm
> pretty sure that's what I hear occasionaly. I didn't cut any holes in
> the podium yet, the units are mounted to wooden blocks which are held in
> place by double-sided tape. I may try some experiments as you mention.
> I might also invest in a different cartridge to see how an omni or
> cardiod would work.

Personally, my experience with pastors and hypercardioids makes me
favor omnis or cardioids. We have a pastor that used to wear a
hypercardioid lav mic, and he would constantly turn his head way
to the side when referring to some information that was being projected
on the screen behind him (such as when he'd turn a read a scripture
passage from a slide). Every time he did that, the sound would get
MUCH quieter. Sometimes he'd talk louder to compensate and then
turn his head back to normal position and the next word or two
he'd say would come out REALLY LOUD and practically startle people.
I managed to compensate somewhat by putting a compressor on that
mic, but it was far from an ideal situation. Plus, the proximity
effect was aweful.

In my opinion, there are a lot of situations where hypercardioids are
just TOO directional. The pickup pattern has to be a balance between
rejecting unwanted noise (and feedback) and actually picking up everything
it is supposed to pick up. Often, the extra benefits of hyper over
regular cardioid aren't that great, and the down sides can outweigh them.

By the way, the church I run sound at has a QSC PLX1602 and five
other QSC amps, and we've never had a problem with any of them.
We've had 3 of them for about 7 years and the other 3 for about 5.
And I'm sad to say that our equipment doesn't necessarily always
get treated well, and some of our other equipment has suffered,
but the QSC stuff has always been fine.

- Logan
Anonymous
June 16, 2005 12:05:31 PM

Archived from groups: rec.audio.pro (More info?)

Logan Shaw wrote:

> Personally, my experience with pastors and hypercardioids
makes me
> favor omnis or cardioids. We have a pastor that used to
wear a
> hypercardioid lav mic, and he would constantly turn his
head way
> to the side when referring to some information that was
being
> projected on the screen behind him (such as when he'd turn
a read a
> scripture passage from a slide). Every time he did that,
the sound would get
> MUCH quieter. Sometimes he'd talk louder to compensate
and then
> turn his head back to normal position and the next word or
two
> he'd say would come out REALLY LOUD and practically
startle people.
> I managed to compensate somewhat by putting a compressor
on that
> mic, but it was far from an ideal situation. Plus, the
proximity
> effect was aweful.

I think the moral of the story is that you have to match the
mic to the application.

For example, we had an associate pastor for whom no lav
would work. When he talked he waved his arms and moved his
body so much that there was a steady cacophony of noises
from his lav.

We had another pastor for whom our cardioid worked like a
charm. The frequency response tailoring perfectly matched
his voice. Almost no equalization was required and he
sounded good and natural.

Our current pastor sounds like a chipmonk with the same mic.
Something about the balance between chest sound, mouth sound
and nose sound, I guess. No amount of eq would provide as
much help as was needed. He always sounded thin and
strident. The change-over to the hypercardiod provided
instant happiness, and with only nominal amounts of eq.

> In my opinion, there are a lot of situations where
hypercardioids are
> just TOO directional.

I agree with that. We've used a hypercardiod as a pulpet mic
and had problems with people who wander off axis or never
get there. I've got some acoustic foam coming to to try to
address the problem with boxiness due to the configuration
of the pulpet. The hypercardiod sounded better, when people
used it right.

However, if you're using mics on stands to cover some
musical instruments or a group of people, there is another
alternative - coincident hypercardiods. I'm constantly
fighting the fact that our speaker cluster is right over the
steps leading up to our platform, and we get a lot of spill
in the upper midrange, particularly from the woofers up
there. the horns are fine. Anything that gets me some
rejection for sound from above is a good thing.

> The pickup pattern has to be a balance between
> rejecting unwanted noise (and feedback) and actually
picking up
> everything it is supposed to pick up.

On balance, cardioids really only reject sound from the
back. Their side rejection is pretty disappointing.

>Often, the extra benefits of
> hyper over regular cardioid aren't that great, and the
down sides can
> outweigh them.

Also remember that the directivity of hypercardiods varies.
In several ways the OM-6 is a vastly different mic from the
rest of the Audix hypercardiods. They are broader and they
have more bass.

> By the way, the church I run sound at has a QSC PLX1602
and five
> other QSC amps, and we've never had a problem with any of
them.

We have three USA400s and a USA850 with similar excellent
results.

> We've had 3 of them for about 7 years and the other 3 for
about 5.
> And I'm sad to say that our equipment doesn't necessarily
always
> get treated well, and some of our other equipment has
suffered,
> but the QSC stuff has always been fine.

So far we've had problems with an ancient Behringer digital
eq (the origional 8000) and of course our Mackie SR32 ribbon
cable special. Speaking of ribbon cables I also had a M1200
amp that had the same problem, but seems fine now that I
paid about half its worth to get it fixed. I had to replace
a voltage regulator chip in a Rane PE-15 eq. Someone dropped
a SM57 and it exploded into a bunch of parts.
!