Help a newb with Bag End ELF equipment

[bigthemat]

Hi all,

So the TL;DR is my brother was gifted this equipment, which was then gifted to me. The original owner was a musician who used this for live audio, he passed away, and his wife gave all the stuff to my bro. I don't know much about anything with live sound, and want to see how viable of an option it would be to use this for live shows.

What I have is the ELF M-2 head/integrator (or whatever it is, again, I'm a newb with this stuff), S18E-I which I think is an 18" cab, and a D10E-I 2x10 cab. The 2x10 has some kind of adapter with a 1/4" input, and the 18 just has two screws (my guess is for old school

I've seen some older posts on here saying some use it for live, some say don't, but I'm a bit confused since the model numbers don't match, and there are specific bass amp/cabs that are different from this setup, which is I think meant to be a PA setup.

So, how usable is this for a live rig? Would it be possible to plug an amp head into the elf integrator, and then connect one or two of the cabs to the integrator, or would it require a lot more stuff to get it to work. I'd imagine the 18" would need some kind of adapter like the 2x10. Also, how reliable is an xlr out to quarter inch going to be?

Thanks!

 

[NapaSmith]

Well. Just saw this. You have an install version on the 18. For live, I'd recommend you get a bag-end replacement Speakon plate so you can plug speaker cables to it. Then you'll need an amp to power the 10" ELF and a second amp to power the top box. You could use a "regular" bass amp for the top box and get a 2nd amp for the sub. I think it will be worth the effort.

 

[Wasnex]

IMHO these will work fine for live use as long as you set up the processor properly and have reasonable expectations. These cabs should sound nice, but they will not produce high SPL at super low frequencies.

First, a bit about what ELF is and how it operates:

ELF systems use sealed drivers that are operated below resonance. Below resonance a sealed driver rolls off at a rate of 12dB per octave. The M2 uses a dual integrator to provide 12dB of boost per octave. This mirrors the cabs roll off and results in a flat frequency response to a very low range.

Cool concept but you don't get something for nothing. As you may know, you need to double the power to get 3dB of additional SPL. So, the cost of this technology is efficiency drops of quickly as the frequency goes down. For the first octave of the ELF process you need to double the power four times to keep the SPL at a constant level. Inevitably you will run out of headroom because the cabs can only take so much power. The M2 has a process called Concealment which is I believe is a sophisticated variable frequency compressor that is designed to mask this problem by limiting sub bass.

Some specifics on your ELF cabs:
Both the D10E and S18E are ELF subwoofers. Both cabs are rated for 400W RMS and 800W program. But there is a big difference in sensitivity. The S18E is rated 96dB 1W/m at 80hz and the D210E is rated 92dB 1W/1m at 80hz. If I remember correctly, I believe 80hz is where the ELF process begins. So the cabs become 12dB less efficient for each octave below 80hz. At 40hz the S18E will be 84dB 1W/1m and the D10E will be at 80dB 1W/1m.

In order to get a full range sound you will need some other type of cab to cover mids and whatever highs you want to hear. Per the spec sheet the High Pass filter can be adjusted from 50hz to 200hz.

You may want to all Bag End to see how well these cabs will pair. Also you may want to ask if SpeakOn jack plates are available. I would experiment with the cabs to make sure they meet your needs before ordering the jack plates.

I will attached the Spec Sheet for the D10E, S18E, and M2. I will also attach the ELF Guide which details the theory behind ELF and gives some hints on how to setup the M2. It's not an easy read.

 

[Downunderwonder]

Dude just wants to know how to plug it in. Next step would be how to not blow it up.

 

[Wasnex]

Dude just wants to know how to plug it in. Next step would be how to not blow it up.

You plug it in like a 2-way crossover with stereo highs and mono lows. The M2 may be configured for Mono 3-way operation as well.

In order to avoid destroying the drivers it would be advisable to read through and develop some understanding of the material I provided. Unfortunately, I don't believe straight forward directions for configuring the features are available, so you have to wade through try and make sense of what I believe was originally a white paper.

I didn't have any trouble setting up the top of the line ELF1 processor when I spec'ed out a Bag End system for my band in the mid 90's. But after I left the group, a guy with a doctorate in physics totally jacked the system configuration. They had to call me back in to get the subs sounding right.

I don't think you would have any trouble with it since you have a fairly extensive background in audio gear and how to set up limiters and crossovers and such. For you it would probably be fairly intuitive after you read through the spec sheets. However, for someone who is not familiar with this sort of stuff, dialing in the parameters can be very confusing. First you need to understand what the parameters do, and then you need to know why the must be adjusted, and finally you need to know how to adjust them. I believe the material I provided only covers the "what" and "why" part. So I will write a bit to try and help the OP understand the "how" part.

The system I spec'ed had the newly introduced QSC PL1.8 amps which were only 400W per channel. Since the subs I had could handle the full RMS power of the amps, I pretty much used my ears and eyes to adjust the Limiters and Concealment so they locked down just before the amps clipped. I.E. I only had to be concerned with how the system sounded by the subs could handle the full power of the amps.

With more powerful modern amps I would try a signal generator and volt meter. In other words I would look at the specs and set the controls to keep the voltage at a safe power level.

The spec sheets for the cabs do not give a minimum impedance, we only have the nominal impedance. I missed something in my earlier analysis. The D10E is 4 ohms and the S18E is 8 ohms. This means the D10E will dissipate twice as many watts at a given voltage. This means in order to compensate so each cab is limited properly, each cab needs to be on its own amplifier channel. This is because the M2 only has one channel of processing for the subs. If both cabs are run on one amplifier channel, I recommend limiting the channel to a voltage level that is safe for the D10E.

A conservative setup would be to set the controls so the amps stay at or below 400W.
For the (8 ohm) S18E, solve the following for V: (400W=V^2/8). In this case V=56.6V RMS. In other words 56.6V applied to 8 ohms results in ~400W.

For the (4 ohm) D10E, solve the following for V: (400=V^2/4). In this case V=40V RMS. In other words 40V applied to 4 ohms results in 400W.

A problem here, is the front panel attenuator on the amp must be adjusted down by ~3dB to produce the desired results. This is a recipe for disaster because someone may accidentally turn the channel all the way up. Then, if both cabs are limited to 56.6V the D10E will fed ~800W, which is probably a bit too aggressive.

Some experimenting is necessary to see how the controls behave.

 

[Downunderwonder]

You plug it in like a 2-way crossover with stereo highs and mono lows. The M2 may be configured for Mono 3-way operation as well.

In order to avoid destroying the drivers it would be advisable to read through and develop some understanding of the material I provided. Unfortunately, I don't believe straight forward directions for configuring the features are available, so you have to wade through try and make sense of what I believe was originally a white paper.

I didn't have any trouble setting up the top of the line ELF1 processor when I spec'ed out a Bag End system for my band in the mid 90's. But after I left the group, a guy with a doctorate in physics totally jacked the system configuration. They had to call me back in to get the subs sounding right.

I don't think you would have any trouble with it since you have a fairly extensive background in audio gear and how to set up limiters and crossovers and such. For you it would probably be fairly intuitive after you read through the spec sheets. However, for someone who is not familiar with this sort of stuff, dialing in the parameters can be very confusing. First you need to understand what the parameters do, and then you need to know why the must be adjusted, and finally you need to know how to adjust them. I believe the material I provided only covers the "what" and "why" part. So I will write a bit to try and help the OP understand the "how" part.

The system I spec'ed had the newly introduced QSC PL1.8 amps which were only 400W per channel. Since the subs I had could handle the full RMS power of the amps, I pretty much used my ears and eyes to adjust the Limiters and Concealment so they locked down just before the amps clipped. I.E. I only had to be concerned with how the system sounded by the subs could handle the full power of the amps.

With more powerful modern amps I would try a signal generator and volt meter. In other words I would look at the specs and set the controls to keep the voltage at a safe power level.

The spec sheets for the cabs do not give a minimum impedance, we only have the nominal impedance. I missed something in my earlier analysis. The D10E is 4 ohms and the S18E is 8 ohms. This means the D10E will dissipate twice as many watts at a given voltage. This means in order to compensate so each cab is limited properly, each cab needs to be on its own amplifier channel. This is because the M2 only has one channel of processing for the subs. If both cabs are run on one amplifier channel, I recommend limiting the channel to a voltage level that is safe for the D10E.

A conservative setup would be to set the controls so the amps stay at or below 400W.
For the (8 ohm) S18E, solve the following for V: (400W=V^2/8). In this case V=56.6V RMS. In other words 56.6V applied to 8 ohms results in ~400W.

For the (4 ohm) D10E, solve the following for V: (400=V^2/4). In this case V=40V RMS. In other words 40V applied to 4 ohms results in 400W.

A problem here, is the front panel attenuator on the amp must be adjusted down by ~3dB to produce the desired results. This is a recipe for disaster because someone may accidentally turn the channel all the way up. Then, if both cabs are limited to 56.6V the D10E will fed ~800W, which is probably a bit too aggressive.

Some experimenting is necessary to see how the controls behave.

I have only dabbled in PA tech and out of my depth to contribute. I think OP is even less experienced and going to need a lot of help to get up to speed.

 

[abarson]

Sometimes you just have to admit it's the wrong tool for the job.
Sell it to someone who knows what it's for and how to use it.

 

[Downunderwonder]

You plug it in like a 2-way crossover with stereo highs and mono lows. The M2 may be configured for Mono 3-way operation as well.

In order to avoid destroying the drivers it would be advisable to read through and develop some understanding of the material I provided. Unfortunately, I don't believe straight forward directions for configuring the features are available, so you have to wade through try and make sense of what I believe was originally a white paper.

I didn't have any trouble setting up the top of the line ELF1 processor when I spec'ed out a Bag End system for my band in the mid 90's. But after I left the group, a guy with a doctorate in physics totally jacked the system configuration. They had to call me back in to get the subs sounding right.

I don't think you would have any trouble with it since you have a fairly extensive background in audio gear and how to set up limiters and crossovers and such. For you it would probably be fairly intuitive after you read through the spec sheets. However, for someone who is not familiar with this sort of stuff, dialing in the parameters can be very confusing. First you need to understand what the parameters do, and then you need to know why the must be adjusted, and finally you need to know how to adjust them. I believe the material I provided only covers the "what" and "why" part. So I will write a bit to try and help the OP understand the "how" part.

The system I spec'ed had the newly introduced QSC PL1.8 amps which were only 400W per channel. Since the subs I had could handle the full RMS power of the amps, I pretty much used my ears and eyes to adjust the Limiters and Concealment so they locked down just before the amps clipped. I.E. I only had to be concerned with how the system sounded by the subs could handle the full power of the amps.

With more powerful modern amps I would try a signal generator and volt meter. In other words I would look at the specs and set the controls to keep the voltage at a safe power level.

The spec sheets for the cabs do not give a minimum impedance, we only have the nominal impedance. I missed something in my earlier analysis. The D10E is 4 ohms and the S18E is 8 ohms. This means the D10E will dissipate twice as many watts at a given voltage. This means in order to compensate so each cab is limited properly, each cab needs to be on its own amplifier channel. This is because the M2 only has one channel of processing for the subs. If both cabs are run on one amplifier channel, I recommend limiting the channel to a voltage level that is safe for the D10E.

A conservative setup would be to set the controls so the amps stay at or below 400W.
For the (8 ohm) S18E, solve the following for V: (400W=V^2/8). In this case V=56.6V RMS. In other words 56.6V applied to 8 ohms results in ~400W.

For the (4 ohm) D10E, solve the following for V: (400=V^2/4). In this case V=40V RMS. In other words 40V applied to 4 ohms results in 400W.

A problem here, is the front panel attenuator on the amp must be adjusted down by ~3dB to produce the desired results. This is a recipe for disaster because someone may accidentally turn the channel all the way up. Then, if both cabs are limited to 56.6V the D10E will fed ~800W, which is probably a bit too aggressive.

Some experimenting is necessary to see how the controls behave.

I don't have a PhD in physics either but a couple of thoughts.

One 'crossover' unit and one of each cab suggests it was used as a biamp bass rig or mono PA. You would have to open it up to check for sure or do detective work on what comes out of the outputs.

Running it from a single amp is a non starter. Need a stereo power amp and a bass preamp.

Also a healthy appetite for RTFMing.

For the socially distant gigs you might be able to find these days it could be quite a nice sounding PA system.

I don't disagree with Agedhorse. It is a big lump of rig not much optimal for rocking out bass guitar and it's not even all there. The specs are overgrown home theatre.

However, free gear is free gear and I am all about getting stuff to work. If you follow the manual instructions you won't blow it up. I'd be interested in how loud of a drummer it can keep with!

 

[Wasnex]

I don't have a PhD in physics either but a couple of thoughts.

One 'crossover' unit and one of each cab suggests it was used as a biamp bass rig or mono PA. You would have to open it up to check for sure or do detective work on what comes out of the outputs.

Running it from a single amp is a non starter. Need a stereo power amp and a bass preamp.

Also a healthy appetite for RTFMing.

For the socially distant gigs you might be able to find these days it could be quite a nice sounding PA system.

I don't disagree with Agedhorse. It is a big lump of rig not much optimal for rocking out bass guitar and it's not even all there. The specs are overgrown home theatre.

However, free gear is free gear and I am all about getting stuff to work. If you follow the manual instructions you won't blow it up. I'd be interested in how loud of a drummer it can keep with!

Both cabs are ELF subwoofers. If the D10E was used as a mid range box, it was not used as designed. Since these are install boxes, I suspect they were originally taken from an install...perhaps a restaurant or swanky bar where volume requirements were relatively low. I believe the ELF MI/PA boxes were the same except different jack panels and different coverings.

These boxes will sound good with bass at fairly low levels. But due to the way ELF works they will not sound the same when you start cranking up the volume. The Concealment circuit pushes up the lower limit of the ELF processing as the volume is pushed. So if you push the system hard enough you get to the point where it sounds like there are no deep lows. There is no nasty distortion like clipping or voice coils bottoming out, the sound just thins out progressively as the SPL goes up.

I would be a lot more optimistic if the OP had a pair of the S18Es. I think there are better choices, but a pair of suitably powered and processed S18E is usable and sounds decent at moderate volume levels. They won't create the sensation of huge fat lows most people would expect from reading the ELF guide though. I think most people would be extremely disappointed.

Still if the OP has a power amp and an inquisitive nature, it would be fun to experiment. Otherwise, consider selling.


The system I spec'ed had four special order S18Cs that were half as deep. The decrease in cabinet volume dropped the sensitivity rating a bit. Each sub was powered by one channel of a QSC PL1.4.

The smaller subs were chosen because the system was designed to put our 5-piece rock band in this type of plane (C21).

When we flew, we only carried two of the subs, but normally the jobs were to entertain small groups of high level military officers and other dignitaries, so relatively low volume was expected. We used a TrapKat for drums and everyone shared a single stereo IEM mix. No instrument amps. We were packed in the plane with our gear like sardines. We did receive beverage and meal service though .

For non-flying gigs we used all four subs, and the system worked really well, even outdoors. Because the system was so small, compact, and easy to setup it was well liked, and it stayed in service for almost 15 years.

The Bag End system was eventually replace by four JBL VRX928 and a pair of VRX915S subs. I am confident a pair of VRX915S will play louder than the four S18s. The JBL system would not fit in a C21, but that mission stopped many years ago.

 

[winston]

I did sound on a large ELF/INFRA PA system for a couple of years. As others have noted, these components will only work properly as part of a well-designed system, meaning enough drivers to balance out the low sensitivity, ample power and suitable mid/high cabinets. I had a chance to compare to other actual pro-audio (Meyer, Adamson, Martin & Turbosound) as well as pro-sumer JBL, EV, Genz-Benz rigs and nothing comes close to the tight, deep punchy bass from an ELF/INFRA system. Any sound person would rightfully want to kill you if you used one in a bass rig, unless you're playing at least big theaters, if not arenas/stadiums.

 

[Wasnex]

Any sound person would rightfully want to kill you if you used one in a bass rig, unless you're playing at least big theaters, if not arenas/stadiums.

I'll offer a couple of comments to contrast this opinion. First, I don't think the gear the OP has would really be sufficient for a loud stadium type gig. It would be of limited use in a relatively low volume situation.

Second, IMHO ELF is not about hyping the low end. If you want hyped lows, there are much better tools because ELF cabs becomes prohibitively inefficient extremely fast.

From the S18E spec sheet:

Maximum Calculated Continuous Acoustic Output:
Half Space @ 1 Meter
10 Hz - 89 dBSPL
20 Hz - 101 dBSPL
40 Hz - 113 dBSPL
80 Hz - 124 dBSPL​

Note the max SPL at 10hz is significantly lower than the sensitivity rating of most musical instrument speakers. The Max SPL at 20hz is in the ball park of the sensitivity rating of many highly rated bass speakers. For those who don't know, the sensitivity rating is typically the SPL a speaker makes with 1 watt when measured at a distance of 1 meter.

ELF's main claim to fame, IMHO, is it extends the response to very low frequencies. But as the spec sheet shows, there is a huge cost in efficiency at the lowest frequencies, so you really need a lot of boxes if you want usable SPL down to the 8hz cutoff claimed by the ELF-1 processor.

There is nothing to say you have to set up the processor to run all the way down to it's lower limit. It's been very long time, but I think I setup the ELF-1 I used with the four S18 compacts to cutoff at 40hz. That seemed to provide a good compromise for the type of music we were playing. The system sounded nice and balanced and the Concealment rarely kicked in in a manner that was obtrusive.

The Nominal cut off for the M2 is 18hz, but you can swap out resistors and move the ELF cutoff up to 70hz. There are plenty of bass cabs with strong response below 70hz. So a bassist could use ELF cabs without causing any more problems than say a couple Greenboy 12/6/1s.

Whether a bassist should use ELF cabs is another story. Overall I think the negatives outweigh the positives when you do a cost/performance work up. I still think ELF was the right call for the system I mentioned earlier, but I had very unusual design requirements.

 

[Downunderwonder]

It comes down to what OP wants out of them and what other gear is available for free already to make use of them, vs if he has any appetite to throw good money at free gear just to make a relatively small noise and have to carry a boatload of gear to do it.

 

[Downunderwonder]

My understanding is the cabs are the bottom end of an overgrown home hifi system that won't thrill too many with oomph before the limiting kicks in/ or if the liimiting is incorrectly set will just blow them up. He is missing amps and preamp.

Specs are noted in the thread. It might make a super hifi bass rig with the right setup and mid high cab, just not LOUD.

 

[J.Wolf]

Very cool legacy rig. Without the knowledge and equipment to resource it properly, results may not be optimal. If you are looking for a great sounding easy to use bass rig, the move might be to flip it, and buy something more conventionally plug-n-play. This is like the vintage Alfa Romeo of bass rigs: super cool, super finicky, will shine when all the boxes are properly checked, and will probably be a headache if not.

This rig is also known by soundmen as: THE INFURIATOR. lol