Finding the Sweet Spot for Subwoofers

[hershon]

Would appreciate any advice on this, so I can have a rough ballpark idea where to start. My question involves how to properly set up a subwoofer excluding location & my receiver is a Denon 3801. Specifically, my Orb Subwoofer's spec's are below. Basically, I can set the crossover, volume and phase control on it. As far as I know Denon has an 80 crossover or am I wrong (I tried calling them up but I could only leave a voice mail)? Does this mean I should set the sub's crossover at 80? What about the volume. Should I set it by a combination of using the Denon receiver's DB's & the sub's volume controls or should
I put the Denon's db's at 0 (which is where my other speakers are) & just turn up the subs volume? How do you set the subs volume up? By trial and error or is there an easier way?

UPER EIGHT SUBWOOFER
Speaker Type High-performance ported bass-reflex design.

Port Type Precision-tuned flared snorkel port.

Amplifier Type & Power Custom high-power class AB amplifier with digital switching power supply for enhanced peak power output

150W (continuous)
400W (peak)

Amplifier THD <.1% (100hz at full power)

Amplifier S/N >95dB

Driver Super long-throw 8" high-performance driver with composite paper/high density ABS cone. This yields rigid, lightweight design with excellent low frequency performance and increased detail and musicality.

Magnet Assembly 30 oz. ferrite magnet

Frequency Response 32-180hz (+/-3dB)
30-180hz (+/-6dB)
Adjustable Crossover (40-160hz)

Max SPL Peak 111dB

Max SPL Long-Term 107dB

Features Phase Switch (0/180)
Adjustable Crossover (40-160hz)
Temperature protect circuitry
Auto/On/Off Power
RCA gold-plated stereo line level inputs
High level gold-plated inputs and outputs
12dB/Octave hi-pass circuit

Weight 26 lbs

Dimensions 12" H x 12" D x 12" W
(optional 1" feet included)

[chimera128]

Your mod 1s are only rated to 80hz... i would set it to the next level up.. if it's 100hz or whatever... and then try it at 80hz. Keep the one that you think sounds the best.

[chimera128]

Also if you sub crossover has more flexibility than the denon.. and you can wire your orbs through the sub.. that is the way i would go.. setting your mains to large. That will send all the LFE to the mains (your orbs wired through the sub) and you will have greater flexibility to mess around with crossover settings.

[anamorphic96]

Hershon you should have the Orbs crossed over where they roll off. From past reading Orb suggests a crossover at 120 or was it 160. Either way use what Orb suggests. So set the Denon to 120 which is the highest I think it goes.

Now for the sub. Set its crossover to off since you are using the Denon's crossover. There may be a switch or sometimes you just turn the crossover knob all the way up to achieve this.

For setting the sub level. Use the test tones that the Denon has and set the sub level to 75db. To achieve this, set the sub volume to halfway and then use the Denon to adjust the sub to 75db. If you end up turning the sub level up all way on the Denon and dont get 75db. Then bring the sub level up to 3/4 and then re adjust the Denon until you get 75db. In case your wondering 75db is the accepted standard at which to set home theatre systems. From what I recall THX is the one to set this standard.

Keep in mind setting levels is tricky unless you have an SPL meter. Especially bass. Human ears are not as sensitive to bass as we are to mids and highs. You can buy an SPL meter at Radio Shack for 30 bucks. Also placement of the sub can have a huge impact on its sound. HUGE IMPACT !!!

Hope this helps.

[shokhead]

Most people set the sub a few db's more then speakers but he's not a big bass guy so start with the sub set at the same db level as your speakers. Like above,put you sub at 3/4 volume and then set and if it to much,just adjust on sub volume after that. You know you might just find out how much bass will add to the enjoyment. It doesnt have to be overbearing or always there.

[Sir Terrence the Terrible]

For setting the sub level. Use the test tones that the Denon has and set the sub level to 75db. To achieve this, set the sub volume to halfway and then use the Denon to adjust the sub to 75db. If you end up turning the sub level up all way on the Denon and dont get 75db. Then bring the sub level up to 3/4 and then re adjust the Denon until you get 75db. In case your wondering 75db is the accepted standard at which to set home theatre systems. From what I recall THX is the one to set this standard.


Hope this helps.

You don't want to set sub levels to the same volume as you set the mains. Bass will sound thin and weak. Sub levels should be set 3-5db higher than the mains based on how loud you listen to movies.

THX didn't set the standard for calibration levels, SMPTE did. However this standard is arbitrary. You can calibrate at 80db, 85db or any other level as long as it is louder than the highest level of background noise.

[topspeed]

THX didn't set the standard for calibration levels, SMPTE did. However this standard is arbitrary. You can calibrate at 80db, 85db or any other level as long as it is louder than the highest level of background noise.
I agree 100% that as long as you calibrate everything at the same levels, whether 75dB or 85dB, you're fine.

I do have a question for you Sir T: I recently read that when a receiver is showing "0", this represents THX Reference level if all of the speakers were intially calibrated to 75dB's. Now, on my rig this would be REALLY LOUD! In fact, I sincerely doubt I could tolerate it for more than a few minutes. Is this right?

[shokhead]

You don't want to set sub levels to the same volume as you set the mains. Bass will sound thin and weak. Sub levels should be set 3-5db higher than the mains based on how loud you listen to movies.

THX didn't set the standard for calibration levels, SMPTE did. However this standard is arbitrary. You can calibrate at 80db, 85db or any other level as long as it is louder than the highest level of background noise.

I know how to set it up but we are talking about someone who doesnt like bass so i'm setting it up light.

[anamorphic96]

I dont know who created it but I do remember THX using 75db as there standard for HT. One thing to note is THX sometimes expands there criteria. This is the case in commercial cinema. They use SMPTE as reference but also expand criteria as they see fit.


However 85 is the SMPTE standard used in commercial movie theatres. While there are some deviations 85 is the standard. DTS sets there surrounds at 82 in a commercial theatre for example. However in a home set up 75db is more reasonable. With a 1 to 3 db boost in the bass. Dependig on your tastes.

[anamorphic96]

I agree 100% that as long as you calibrate everything at the same levels, whether 75dB or 85dB, you're fine.

I do have a question for you Sir T: I recently read that when a receiver is showing "0", this represents THX Reference level if all of the speakers were intially calibrated to 75dB's. Now, on my rig this would be REALLY LOUD! In fact, I sincerely doubt I could tolerate it for more than a few minutes. Is this right?

Good question. When setting levels for HT I have always set them with the fader at 0. Makes sense. In commercial theatres the fader is set to 7 then levels are calibrated. On the Dolby processor 7 is considered Dolby reference level. However turning up the movie to this level with only 100 people in a 300 seat house is going to be very loud. 7 is used when the house is full.

[Sir Terrence the Terrible]

I agree 100% that as long as you calibrate everything at the same levels, whether 75dB or 85dB, you're fine.

I do have a question for you Sir T: I recently read that when a receiver is showing "0", this represents THX Reference level if all of the speakers were intially calibrated to 75dB's. Now, on my rig this would be REALLY LOUD! In fact, I sincerely doubt I could tolerate it for more than a few minutes. Is this right?

I agree, 0 reference on a THX reciever is insanely loud( I also have a THX reciever). If I listened that loud, my subs would be doing something like 117-120db, and the mains about 108-110db peak. There is no way in hell I could tolorate anything that loud.

I know that dubbing stages are calibrated at 85db, and I have to wear earplugs just to work in that environment.