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View Full Version : reference levels with 340s/170s please advise



shawn784
06-07-2008, 04:12 PM
i have an onkyo sr805 receiver

my setup currently is 4 170s with a 340center but soon i will have a 340 center and fronts with 170 rears and i have to decide if i want to keep the other 170s to have 7.1 or return them and settle on 5.1

will i be able to push this speakers to reference levels without damage?

the volume control is from -50 to +18 where 0 is reference level i assume. I have never had them pushed above like -17 with a lossless source and -10 with a lossy source

also will any damage occur if i do not set a crossover point?
i currently am using 80hz but there is a mode called pure audio that turns off the crossover settings should i be concerned when listening in this mode?

thanks in advance for the replies

curtis
06-07-2008, 05:20 PM
I posted some of this over at AVS...

That volume control range is only arbitrary. 0 is reference only if you have calibrated it that way.

Do you have an SPL meter? How far away do you sit from the speakers?

shawn784
06-07-2008, 08:46 PM
i used the Audyssey MultEQ XT with the mic.

i do not have a spl meter

what should the db level be at reference?

curtis
06-07-2008, 11:24 PM
Dolby Reference Level is defined as 105 dB PEAKS at the listening position. The LFE can be 115 dB.

shawn784
06-07-2008, 11:40 PM
i will be getting an spl meter i assume a radio shack one shall suffice

maybe i should rephrase my question. if my tonal settings on the sr805 are all set to 0db and a few to like -2db and the sub is -4. Audyssey did all of that. Running the receiver at the 0 volume setting in 5 channel stereo will this introduce any distortion or clipping that could possibly damage the speakers?

obviously i do not listen to them at that level while in the room but i have a very open floor plan and say if im washing dishes or doing something around the house will it hurt them to play it at the 0 level.

My assumption is that it will not since there is still +18 to go on the knob
so if the range is -50to +18 that means i am 50/68 of its power or 73.5%

let me know what you think as i have only tinkered with it to that level once while listening to some nirvana and it was only for like 10 seconds. for those 10 seconds it sounded good to me but i am no audiophile and dont have much experience with home audio equipment. It hurt my ears and i turned it down to like -10

Also i am very impressed with your response times and your number of posts. Its nice to see someone who is dedicated and cares about helping others in the home theater realm

curtis
06-08-2008, 12:31 AM
The issue is that with your receiver at 0 or at -18 and without at meter, we do not know how loud it is.

Like I mentioned earlier, the numbers you are referring to really do not correspond to anything and I don't think you can make assumptions to power output.

My gut feeling is that you are fine though.

Maybe someone else that owns a SR805 can answer better.

shawn784
06-08-2008, 01:54 AM
once i get my spl meter and mess around with the setting i will update this thread

thanks

Mike^S
06-08-2008, 02:40 PM
The 340SE and 170s have pretty high sensitivity, so you should have no problem hitting reference levels. However, it does depend on how far away from the speakers you are. The 805 is pretty beefy for a receiver. I saw some measurements in a review that showed it hitting 180 watts/channel with 2 channels driven and 0.1% distortion. In five channel mode I think it hit around 150 watts/channel.

What kind of subwoofer do you have? Make sure you cross over the speakers to the sub at 80hz.

Also keep in mind, reference level is pretty loud and is rarely needed.

shawn784
06-08-2008, 06:43 PM
yeah i bought the 805 over the 705 because i wanted the extra headroom and play it at a reasonable level without having to worry about distortion. Figured the extra 30watts a channel and bigger power supply would do that.

Got my spl meter today and am reading up on calibration.

my current sub is a jbl pb12 250 watt but is being replaced by a av123 mfw 15 in july because they are on backorder.

all speakers are crossed over at 80hz and the sub plays everything below that.

davef
06-09-2008, 11:27 PM
Hi Shawn,


maybe i should rephrase my question. if my tonal settings on the sr805 are all set to 0db and a few to like -2db and the sub is -4. Audyssey did all of that. Running the receiver at the 0 volume setting in 5 channel stereo will this introduce any distortion or clipping that could possibly damage the speakers?

It is really impossible to answer that question. I would have to know precisely what the voltage output of the receiver is at the "0" dB level. Curtis is correct, the 0dB level is just an arbitrary number and audio volume controls are generally logarithmic, not linear, meaning, 50% level of the volume control does not mean 50% of the available power.

Our CBM-170 SE and 340-SE are efficient loudspeakers and capable of surprising output levels. If you are playing the system loudly and you hear mechanical distress or distortion, simply turn the volume down. I suspect you will never reach this point and I don't recommend it for the safety of your own hearing, but... don't be afraid to push it either :p We use very high quality components, absolutely the very best at this price point and they can handle loads of clean power.

Enjoy!

shawn784
06-10-2008, 01:01 AM
thanks for the reply. after calibrating the system it is almost dead on for 105 db at 0 volume. also the settings have very little trim gains at all. amazing considering the size of the room is about 20x15. I guess the wood floors might help some.

So yes these speakers do seem to be very efficent in one's house.

I was just concerned about damaging my investment as i am sure many people are after spending 1k or more on speakers. Now while that may not be alot of money to some people nor may these speakers be for everyone I think they sound excellent and were a huge upgrade over my jbl northridge speakers and i just wanted to be safe than sorry.

Thanks to dave and curtis for replying to this thread

davef
06-10-2008, 10:46 PM
Hi Shawn,

I am pleased that it all worked out :)

Enjoy!!