Revisiting Pro amplifiers for home use

[Rudy81]

Stormin, I really liked the K1 as well and the sound quality was excellent. However, between the amp and the heat from my projector lamp, it could get fairly roasty in my HT during those hot Texas summers. The Behringers run very cool with the little power I use and the fan mod makes them very quiet. I had no way of locating the K1 in a different location to take care of the heat problem. So, I decided to sell it.

After a double feature, the room would get rather uncomfortable due to the heat radiation from that amp. In that case, a quiet fan was better than a heater in the room.

[Rudy81]

This coming week I would like to decide which amps use for my HF drivers. Options are to keep the Hafler amps, get the QSC PLX2, or go with the EP4000.

I am going to use the EP 4000 for my side and rear effects speakers.

[Rudy81]

2. The lower line level from consumer gear vs. pro amplifiers; with both the QSC and the Crown before it, I had to turn up the gain on the amp all the way, and set the sub output in my HT processor way higher than 0 to get the proper balance. This seems inefficient to me, so I have a Samson S-Convert on the way (similar to the ART Cleanbox, but without the sub-30 Hz cutoff), and am hoping to find a better balance with this.

I am otherwise very pleased with the aesthetics, build quality, and sonics of the QSC.

Interesting you have run into this problem. When I first started with an active crossover I had some issues which led me to the S-convert. But, I found that box to have a 'popping' sound when turned on. I ended up sending it back and just working with direct connections from consumer to pro audio.

I have not run into the issues you describe going from my Integra, via XLR, to my active crossover and then to the amps. I have checked with others that have gone direct from a pre/pro to an amp and they have not mentioned the issue as severe as yours. I wonder if it depends on the particular source component.

Next week I am going to go from my pre/pro to a Behringer amp for my passively crossed effects speakers. I hope I don't run into that issue.

I do know there are some pro amps out there that allow you to switch the sensitivity to match consumer gear. Right now I don't recall which ones, but I have heard or read about some. You might want to look into that to solve your sensitivity issue.

Interestingly, none of my amps are at maximum sensitivity. The highest setting on any is half way on the amp. Otherwise, they are too loud and out of balance in the other direction.

[wuzzzer]

Just in case someone didn't notice, member fyrpwr is selling two NIB Crown XTi 1000 amps for $260 each + shipping!

http://forums.klipsch.com/forums/t/144771.aspx

[chuckears]

2. The lower line level from consumer gear vs. pro amplifiers; with both the QSC and the Crown before it, I had to turn up the gain on the amp all the way, and set the sub output in my HT processor way higher than 0 to get the proper balance. This seems inefficient to me, so I have a Samson S-Convert on the way (similar to the ART Cleanbox, but without the sub-30 Hz cutoff), and am hoping to find a better balance with this.

I am otherwise very pleased with the aesthetics, build quality, and sonics of the QSC.

Interesting you have run into this problem. When I first started with an active crossover I had some issues which led me to the S-convert. But, I found that box to have a 'popping' sound when turned on. I ended up sending it back and just working with direct connections from consumer to pro audio.

I have not run into the issues you describe going from my Integra, via XLR, to my active crossover and then to the amps. I have checked with others that have gone direct from a pre/pro to an amp and they have not mentioned the issue as severe as yours. I wonder if it depends on the particular source component.

Next week I am going to go from my pre/pro to a Behringer amp for my passively crossed effects speakers. I hope I don't run into that issue.

I do know there are some pro amps out there that allow you to switch the sensitivity to match consumer gear. Right now I don't recall which ones, but I have heard or read about some. You might want to look into that to solve your sensitivity issue.

Interestingly, none of my amps are at maximum sensitivity. The highest setting on any is half way on the amp. Otherwise, they are too loud and out of balance in the other direction.

My Crown K1 had a switch for higher sensitivity, but it still required being turned on full, with the settings I previously described. Perhaps subwoofers require a higher output signal than full-range speakers?

Not too worried about the "popping sound", since I tend to leave my processor and amps on all of the time, which will include leaving the S-Convert turned on...

[Rudy81]

chuckears, just for comparisson, I ran my two DBB bass bin, 2 15" drivers each bin" with a K1 and the sensitivity knobs were set at just past the mid point with plenty of bass to spare. I did have a Crown XLS 602 that ran wide open to push my passive RSW-15's. I now have the RSWs on a Behringer EP4000 and that is set around mid way. I suspect it may have to do with the output of your pre/pro. I am also using the XLR connections of my pre/pro vs. the RCA outs. I don't know if there is a voltage difference there.

[Kain]

Pete H, any updates or a review? I am also considering QSC amplifiers for our home theater.

[Rudy81]

Just finished adding the last of the EP4000s for my side and rear effects speakers. Total of 5 EP4000s and it is darn quiet in there. I continue to debate using QSC for the HF drivers, but two of those would be expensive and severe overkill. Not that overkill ever stopped me before. For now, the Hafler will conitnue to power the HF drivers until I figure out what will come next, Faital Pro drivers or horns....or nothing.

[Pete H]

Pete H, any updates or a review? I am also considering QSC amplifiers for our home theater.

I just received it yesterday and I plan on giving it a listen this evening so I will post as soon as I do.

[CECAA850]

Just finished adding the last of the EP4000s for my side and rear effects speakers. Total of 5 EP4000s and it is darn quiet in there. I continue to debate using QSC for the HF drivers, but two of those would be expensive and severe overkill. Not that overkill ever stopped me before. For now, the Hafler will conitnue to power the HF drivers until I figure out what will come next, Faital Pro drivers or horns....or nothing.

5 EP4000's and a concern that 2 QSC's are overkill. You HAVE to see the irony there. Do you have 2 or 4 HF drivers?

[Rudy81]

5 EP4000's and a concern that 2 QSC's are overkill. You HAVE to see the irony there. Do you have 2 or 4 HF drivers?

I actually have three HF drivers, one for each L, C, R channels.

I'm sure the power in the amps is a bit of overkill, but in reality, all I have done is swapped out amps. I already had that much amplification for a 7.1 system with quad subs. I have two TH subs for LFE, two RSW-15s in passive setup crossed with my mains, four 15" woofers in the mains. That takes care of two amps and the other two are now powering the side and rear effects speakers.

[CECAA850]

Gotcha. You really only need an amp and a half, but unfortunately they don't come that way. That's why I've got 4 amps (8 channels) for 7 speakers.

[Rudy81]

Gotcha. You really only need an amp and a half, but unfortunately they don't come that way. That's why I've got 4 amps (8 channels) for 7 speakers.

Exactly! Right now the Haflers are doing a great job with the HF drivers. However, if I decide to try the Faital Pro drivers at 16 Ohms, I might need a little more power, which is what started the HF, QSC idea.

I'm still waiting to see the results of the elliptrac horns guys are trying out.

[Pete H]

Pete H, any updates or a review? I am also considering QSC amplifiers for our home theater.

I just received it yesterday and I plan on giving it a listen this evening so I will post as soon as I do.

I finally got the QSC running to give it a listen so I thought I would post my initial impressions [][Y][8][][][][Y][], but I'm not sure how to express it.

This was just a short lived throw together listening session but here was the chain of equipment;

Sony S7700 into the mixing board

Main outs XLR to 1/4's into the QSC and another set of main outs 1/4's to the Carver's with adapters.

Monitor outs to 1 RSW 15

QSC to the Cornscala's (Dean's passive crossover's[Y])

I also ran this set up with 2 pair of RB 5's and the sub to easily A/B the QSC against the Carver's (Carver's were bridged)

Here's what I observed; the QSC was quiet and even at low levels, the "infamous" fan noise, didn't factor into the equation at all and even if I wasn't considering remotely locating the amps, I wouldn't think about changing out the fans. I don't want to start a discussion about fan noise, as I'm sure that there are fans in pro equipment that can be objectionable in a quiet listening environment, but for those that hear the whispers of a moth's wings, prior to the moth taking flight, I would suggest turning it up just a little, or getting out of the path of the fan, as it might actually cause a rift in the time and space continuum and fly's farting would disrupt the humans that are trying to sleep.[]

I set the QSC to roll off at 50, which is a little lower than I would normally set the Cornscala's with the 15's, but running the sub off of the monitor outs from the board allowed me to dial in the sub easily.

When I ran the amps with a couple of sets of my RB5's all that I can say is that I'm really happy about the QSC purchase, but the Carver's(20 years old and bridged) didn't slack at all and I can't say that I would choose one set up over the other.

This is one of those situations that requires this particular QSC to be listened to side by side with other pro amps in order to get a true assessment of how it stacks up; and I'm not in a position to do that now as it's the first pro that I've purchased. I can only repeat how [] I am with what I'm hearing.....................if it wasn't for that dam* fan. ROTFLMAO, To all, have a great night.

[chuckears]

Pete,

Your fans must have been better, newer, or a different model than, the one in my (used) RMX2450... it literally sounded like a small vacuum cleaner was running when it was turned on. Painfully obvious, even to my wife, whose hearing is not nearly as acute as mine. The $8 Digikey fan I put in its place has no whine, just a low-pitched whoosh from the air movement.

Since these amps are made for live music, stacked in a pro rack, I'm sure it is not a concern of the fine folks at QSC, but for home use, at least for me, the noise was way intrusive, espcecially during quiet passages in music or film.

Glad these are working out for you; mine is powering my two subs, and I have not yet had a chance to hear everything of which it is capable...

[Pete H]

Pete,

Your fans must have been better, newer, or a different model than, the one in my (used) RMX2450... it literally sounded like a small vacuum cleaner was running when it was turned on. Painfully obvious, even to my wife, whose hearing is not nearly as acute as mine. The $8 Digikey fan I put in its place has no whine, just a low-pitched whoosh from the air movement.

Since these amps are made for live music, stacked in a pro rack, I'm sure it is not a concern of the fine folks at QSC, but for home use, at least for me, the noise was way intrusive, espcecially during quiet passages in music or film.

Glad these are working out for you; mine is powering my two subs, and I have not yet had a chance to hear everything of which it is capable...

I was just playing around with the fan comments.[] and keep in mind that I haven't set this up in my HT at this point so I haven't listened to it with anything but a couple hours of music and after reading some other threads I was expecting a jet engine, but the fan really wasn't any problem at my normal listening levels. I'm going to give it a listen with the 7's and see how they like the QSC.

[DrWho]

Yikes, I'm not sure I'd be able to hear a difference between amps running the source through a Behringer mixing console [] (same goes for the Mackie board they ripped off).

[Rudy81]

Yikes, I'm not sure I'd be able to hear a difference between amps running the source through a Behringer mixing console (same goes for the Mackie board they ripped off).

That was generally my experience comparing one of my old Haflers to an EP4000. The only difference I noted was that the Hafler sounded just a little bit more laid back, but that could easily be because the old amp just has old components, caps etc. I don't know if that makes a difference or not in amp sound. I suppose a good amp just amplifies the signal without adding to or subtracting from the source.

I know lots of folks like to bash Behringer, but thus far my experience has been good for HT use. I still use my DCX2496 which is darn good for the money. Granted, the quality is not there when compared to my Ashly, but the price difference is large too.

As far as fans go, I have found the following. For home use, the stock fan in the EP4000 is not acceptable. It was not as loud as the jet engines in my Crown XLS, but still loud enough to be annoying when no music is playing. The $8 Digikey fan is a huge improvement, but does produce a barely noticeable 'whoosh' airflow noise. I recently tried the Digikey $24 fan (Item number 381-2502-ND) which is listed as 12dB. Those fans are darn near silent from the front of the amp. I had all 5 amps running and couldn't hear any fan noise at all from my sitting position. In fact, I had to put my hand next to the amp to verify airflow. After a two hour movie and an hour or so of reference level music, the hottest air temp in any of the amps was 78 degrees F. I'm thinking the expensive fans will work just fine.

[Pete H]

Yikes, I'm not sure I'd be able to hear a difference between amps running the source through a Behringer mixing console (same goes for the Mackie board they ripped off).

It's all I had a chance to hook up last night, but will be listening to it through the Carver and the Onkyo 805 so the Behringer won't be part of the chain. I also agree with Rudy in regards to Behringer getting a bad rap in some cases as I've had no problems with any of it and when I run the guitar through it instead of directly into the amp I don't notice any significant changes in the sound coming out of the amp when there's no EQ or effects.

[Kain]

Pete H, any updates or a review? I am also considering QSC amplifiers for our home theater.

I just received it yesterday and I plan on giving it a listen this evening so I will post as soon as I do.

I finally got the QSC running to give it a listen so I thought I would post my initial impressions , but I'm not sure how to express it.

This was just a short lived throw together listening session but here was the chain of equipment;

Sony S7700 into the mixing board

Main outs XLR to 1/4's into the QSC and another set of main outs 1/4's to the Carver's with adapters.

Monitor outs to 1 RSW 15

QSC to the Cornscala's (Dean's passive crossover's)

I also ran this set up with 2 pair of RB 5's and the sub to easily A/B the QSC against the Carver's (Carver's were bridged)

Here's what I observed; the QSC was quiet and even at low levels, the "infamous" fan noise, didn't factor into the equation at all and even if I wasn't considering remotely locating the amps, I wouldn't think about changing out the fans. I don't want to start a discussion about fan noise, as I'm sure that there are fans in pro equipment that can be objectionable in a quiet listening environment, but for those that hear the whispers of a moth's wings, prior to the moth taking flight, I would suggest turning it up just a little, or getting out of the path of the fan, as it might actually cause a rift in the time and space continuum and fly's farting would disrupt the humans that are trying to sleep.

I set the QSC to roll off at 50, which is a little lower than I would normally set the Cornscala's with the 15's, but running the sub off of the monitor outs from the board allowed me to dial in the sub easily.

When I ran the amps with a couple of sets of my RB5's all that I can say is that I'm really happy about the QSC purchase, but the Carver's(20 years old and bridged) didn't slack at all and I can't say that I would choose one set up over the other.

This is one of those situations that requires this particular QSC to be listened to side by side with other pro amps in order to get a true assessment of how it stacks up; and I'm not in a position to do that now as it's the first pro that I've purchased. I can only repeat how I am with what I'm hearing.....................if it wasn't for that dam* fan. ROTFLMAO, To all, have a great night.

What are the specs of your Carver amplifier? Did you get a chance to try the QSC with the RF-7s?