ProSoundWeb Community

Please login or register.

Login with username, password and session length
Advanced search  

Pages: [1] 2  All   Go Down

Author Topic: Subwoofer comparisons.  (Read 11961 times)

Brandon Wright

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 97
Subwoofer comparisons.
« on: May 10, 2012, 12:16:06 pm »

Hello,

I am currently in the process of putting together a proposal for the purchase of some new subwoofers for the University I work for. Currently, we have been using 4 EV Mtl-4's and I would like to replace them with Danley TH118's. However, when I went to compare the sensitivities between the two cabinets I was surprised at how the Mtl-4's stood up. Don't get me wrong they get loud and sound good for most rock stuff, but I figured they would pale in comparison to the TH118 that everyone has been speaking so highly of. Unfortunately, I have yet to hear them. The TH118's still have many other advantages that make them appealing to me, i.e. weight and portability.

Basically, I was hoping you guys could check my work on the sensitivity comparison and provide any input you have on the two. I subtracted 3db across the board on the TH118 to get to 1w/1m and added 6db to the Mtl-4 to get a half space measurement because the graphs were measured in an "anechoic environment." Seem correct to everyone?
Logged

Elliot Thompson

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 65
Re: Subwoofer comparisons.
« Reply #1 on: May 10, 2012, 03:42:58 pm »

Hi.

It appears you are overlooking something. The Electrovoice MT-4 is a 2-ohm cabinet. So it takes four eighteens housed in the manifold to bring forth those dB ratings @ 1-watt, 1 metre.

The Danley TH 118 uses one 18-inch driver.

So if you compared four Danley TH 118’s to one Electrovoice MT-4, the 1-watt, 1-metre measurements will be higher on the Danley TH 118. That is of course, if the Danley TH 118 is 8-ohm. If it is 4 ohms, you will still have approximately +3 dB more @ 1-watt, 1-metre using two Danley TH 118 versus one Electrovoice MT-4.

Best Regards,

Logged

Brandon Wright

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 97
Re: Subwoofer comparisons.
« Reply #2 on: May 11, 2012, 11:53:30 am »

Hi.

It appears you are overlooking something. The Electrovoice MT-4 is a 2-ohm cabinet. So it takes four eighteens housed in the manifold to bring forth those dB ratings @ 1-watt, 1 metre.

The Danley TH 118 uses one 18-inch driver.

So if you compared four Danley TH 118ís to one Electrovoice MT-4, the 1-watt, 1-metre measurements will be higher on the Danley TH 118. That is of course, if the Danley TH 118 is 8-ohm. If it is 4 ohms, you will still have approximately +3 dB more @ 1-watt, 1-metre using two Danley TH 118 versus one Electrovoice MT-4.

Best Regards,

Well, I was looking to compare the two cabinets directly. Yes the MT4 has more drivers and a lower impedance, but that is why it is standardized at 1w/1m. I understand that 1 watt into the Mtl-4 is less voltage than 1 watt into the TH118. Basically, I am looking to replace the 4 Mtl-4's with 4 TH118's. However, I think it may take more than four to get much of an increase in output over the Mtl-4's, which surprised me. Thoughts?
Logged

Christopher Gennette

  • Newbie
  • *
  • Offline Offline
  • Posts: 3
Re: Subwoofer comparisons.
« Reply #3 on: May 11, 2012, 12:29:42 pm »

I subtracted 3db across the board on the TH118 to get to 1w/1m and added 6db to the Mtl-4 to get a half space measurement because the graphs were measured in an "anechoic environment." Seem correct to everyone?
[/quote]

No it doesn't.  If you subtract 3db from Danley because it is a 4 ohm box, then you need to subtract 6db from the Mtl-4 because as Elliot pointed out it is a 2 ohm box.  Further the "anechoic environment" may actually favor the Mtl-4 over Danley's real world measurements which are measured at 10 meters...
Logged

Brandon Wright

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 97
Re: Subwoofer comparisons.
« Reply #4 on: May 11, 2012, 12:37:06 pm »


No it doesn't.  If you subtract 3db from Danley because it is a 4 ohm box, then you need to subtract 6db from the Mtl-4 because as Elliot pointed out it is a 2 ohm box.  Further the "anechoic environment" may actually favor the Mtl-4 over Danley's real world measurements which are measured at 10 meters...

I subtracted 3db because danley uses a 2.83v standard, I didn't think I needed to subtract from the EV measurement because it was already at a 1w/1m standard. They way they are both receiving one watt, different voltages, but one watt.
Logged

Scott Harris

  • Subwoofer forum
  • Full Member
  • *
  • Online Online
  • Posts: 248
  • Worcester, MA
    • Running Sound
Re: Subwoofer comparisons.
« Reply #5 on: May 11, 2012, 12:40:28 pm »

But don't you want at equalized voltage comparison, not wattage?
Logged

Elliot Thompson

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 65
Re: Subwoofer comparisons.
« Reply #6 on: May 11, 2012, 02:28:15 pm »

Well, I was looking to compare the two cabinets directly. Yes the MT4 has more drivers and a lower impedance, but that is why it is standardized at 1w/1m. I understand that 1 watt into the Mtl-4 is less voltage than 1 watt into the TH118. Basically, I am looking to replace the 4 Mtl-4's with 4 TH118's. However, I think it may take more than four to get much of an increase in output over the Mtl-4's, which surprised me. Thoughts?


I can understand you are trying to make all things considered equal. However, you seem to having difficulty understanding why impedance plays a factor.

Lets look at from an amplifier’s perspective. If you feed a single Electrovoice MT-4 2000 watts (500-watt a driver) you will need an amplifier capable of deliver 2000 watts per channel @ 2 ohms.

If you feed a single Danley TH 118 2000 watts, you will require an amplifier that delivers 2000 watts per channel @ 4 ohms.

All things considered equal.

Right!

If the amplifier driving the Danley TH 118 offers 4000 watts per channel @ 2 ohms and, you decide add an additional Danley TH 118 (Totalling two) on a single channel of the amplifier, you will now have 4000 watts which is 3 dB louder than 2000 watts using two drivers (Danley TH 118, 4-ohm per cabinet) versus four drivers (Electrovoice MT-4, 2-ohm a single cabinet) getting 2000 watts.


Do you see how impedance plays a factor once the amplifier comes into play?

As you have pointed out the differential in terms of sensitivity amongst both cabinets @ 1-watt, 1-metere is very close. However, the nominal load of each cabinet differs by two. This will play a factor on the overall results once the amplifier is added to the equation. For although you are trying to make all things considered equal, the impedance between the Electrovoice MT-4 and, Danley TH 118 are not the same.

Best Regards,

Elliot.
« Last Edit: May 11, 2012, 09:09:40 pm by Elliot Thompson »
Logged

Chris Hindle

  • SR Forums
  • Hero Member
  • *
  • Offline Offline
  • Posts: 1560
  • Montreal, Quebec, Canada, Earth, Sol System,......
Re: Subwoofer comparisons.
« Reply #7 on: May 14, 2012, 01:37:19 pm »

Hi.

It appears you are overlooking something. The Electrovoice MT-4 is a 2-ohm cabinet. ......
The last one's I used were 2 x 4 ohm load to the NL-4's. I think it was paired 1&2 and 3&4.
(I remenmber, because I had to build the cables last minute to add another 8 boxes to "our" 24 box rig. Our boxes had NL-8, with the 18's paired for 4 ohm loads)
BTW, I would never call them subwoofers. They were a mighty inpressive low end box, but certainly not Subs.
Logged
Ya, Whatever. Just throw a '57 on it, and get off my stage.

Jeffrey Knorr - CobraSound.com

  • Full Member
  • ***
  • Offline Offline
  • Posts: 134
    • CobraSound.com
Re: Subwoofer comparisons.
« Reply #8 on: May 21, 2012, 11:07:58 pm »

Hi Brandon,

Comparisons on paper aren't usually worth the paper that they're printed on.  In this case you have two completely different measurement environments/methodologies at play which makes a direct comparison very difficult.

The TH118's are definitely impressive subs but MTL-4's loaded with FOUR 18" drivers should be no slouches either.  My understanding of the Tapped Horn is that it roughly doubles the performance of the driver(s) used--i.e. you get positive summation of the front and rear output from the driver(s).  The TH118 uses the Tapped Horn to help raise its efficiency, whereas the MTL4 uses more physical cones.  It shouldn't come as a surprise that the MTL4 with so many drivers and slightly higher box tuning is very efficient.

You may want to expand your comparison to additional factors as well:
-Sound quality
-Low Frequency extension
-Size/Weight
-Availability
-Cost (including amplifiers, processing, truck space, warehousing space, labor, etc.)

Where are you located?  If I were you, I would try to arrange a demo or get a serious hands on listen so that you have more that spec sheets to go on.

Jeff
Logged

Peter Morris

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1243
Re: Subwoofer comparisons.
« Reply #9 on: May 22, 2012, 09:19:59 am »

Hello,

I am currently in the process of putting together a proposal for the purchase of some new subwoofers for the University I work for. Currently, we have been using 4 EV Mtl-4's and I would like to replace them with Danley TH118's. However, when I went to compare the sensitivities between the two cabinets I was surprised at how the Mtl-4's stood up. Don't get me wrong they get loud and sound good for most rock stuff, but I figured they would pale in comparison to the TH118 that everyone has been speaking so highly of. Unfortunately, I have yet to hear them. The TH118's still have many other advantages that make them appealing to me, i.e. weight and portability.

Basically, I was hoping you guys could check my work on the sensitivity comparison and provide any input you have on the two. I subtracted 3db across the board on the TH118 to get to 1w/1m and added 6db to the Mtl-4 to get a half space measurement because the graphs were measured in an "anechoic environment." Seem correct to everyone?

Hi Brandon,

I think your math is correct, however in use the MTL donít seem to live up to that specification.  I suspect itís because the driver (DL18MT) has only about 5.5 mm of Xmax, compared to the latest crop of 18s that are about 1 dB more efficient and have about 14mm of Xmax, handle more than 3 times the power, and have much less thermal compression.

http://www.bcspeakers.com/product.php?id=162
http://www.eighteensound.com/index.aspx?mainMenu=view_product_simple&pid=298

The MTLís sound fairly ordinary and donít go that loud or low by todayís standards.  I would suggest any of the new generation of double 18s using drivers such as those above would be more than a match for an MTL4.  I have never heard the Danleys so I cannot comment,  but I believe they are using a driver with similar specs to those above.
« Last Edit: May 26, 2012, 10:26:21 pm by Peter Morris »
Logged
Pages: [1] 2  All   Go Up
 


Page created in 0.029 seconds with 21 queries.