Adding a sub

0 Members and 1 Guest are viewing this topic. Read 2820 times.

Carlman

Adding a sub
« on: 17 Aug 2004, 01:44 am »
I've been battling for some time with a sub... I won't go into all the details but it involves some customer service issues and other non-audio things as well.  The sub is a custom cabinet, Hypex 200w plate amp, and an Adire 10" driver.... w/ XBL2 technology!  :o  (I don't know what that means exactly, just trying to help identify the driver.)

Also, I have no experience with integrating a sub.  It has taken me about 5 months to finally get to where I like it.  It blended fairly well with a pair of Von Schweikert VR1's but I couldn't seem to get it to blend well with my Green Mountain Audio Europa's.  

I'm now trying the Usher X-718 as a demo and have found the sub to be quite a nice addition to these speakers using an 8 watt tube amp for the upper end of the frequency range.   I have the RCA connectors going from the preamp to the plate amp (Hypex 200), and then out to the 8w Minimax after being crossed over at 80Hz.

The Usher's had a bit of bass 'bloom' in the lowest octave and now they don't get to that octave... However, the sub goes much deeper, and cleaner to present the bass detail much better than I expected.  

I guess some of the stuff Doug S. suggests could possibly work! ;)  Now I just need 2!  :lol:

Seriously, I could see how a good crossover and a sub could yield excellent results w/ 1 or 2 subs.  

Anyway, I don't really have a point other than I'm just confused as to how 1 day something won't work for me and then I try it again and it does.  I've really enjoyed having the sub running tonight.  It adds a nice dimension to the music, bass details... and lets the Minimax's magic come through the top end.

If you want to relate in some way to my ramblings, please post away... I'm just a bit surprised.  I'm going to have to review what I changed...

-C

bubba966

Adding a sub
« Reply #1 on: 17 Aug 2004, 01:48 am »
Good to hear you finally got that little 10" Adire working for you. I was having a hard time figuring out why it wasn't working for you as I found that little driver to be quite impressive when I heard it in the CSS sub...

Inscrutable

  • Full Member
  • Posts: 414
    • http://home.earthlink.net/~inscrutabl/index.html
Adding a sub
« Reply #2 on: 17 Aug 2004, 09:46 am »
I, too, had never gotten satisfied with the integration of my sub(s) for music.  Perhaps I was too dumb to get it right, perhaps the room wouldn't allow it, perhaps the juice wasn't worth the squeeze as my various mains have always been strong to at least 40-50 Hz (so there wasn't enough incentive to work harder to get it right).

However, I am certain that my next setup will involve mains and amps that will provide me much greater incentive to improve the foundation.

Inscrutable

  • Full Member
  • Posts: 414
    • http://home.earthlink.net/~inscrutabl/index.html
Adding a sub
« Reply #3 on: 17 Aug 2004, 09:48 am »
Carl,
I'd be glad to bring the Behringer over sometime if you'd like to see the effect of what you're doing.

Mike Dzurko

  • Industry Participant
  • Posts: 2447
Adding a sub
« Reply #4 on: 17 Aug 2004, 12:30 pm »
Carl:

I've found that it is easy to get a sub to sound okay, but it takes patience and time to make it completely transparent. Sometimes just an 1/8" turn of the volume, or phase or crossover can make all the difference in the world.  Test instruments help tremendously as you can see what is going on instead of guessing. ETF or and inexpensive RTA like True Audio's are a fantastic help. I always end up doing the final adjustments by ear with music, but the instruments get me close far quicker than I can do by ear.

Setting up a sub(s) is a little bit like photography, easy to get a good picture, much more difficult to get a great one.

Customers call and email every day with some variation of "got the sub an hour ago and it doesn't yet sound perfect, tell me exactly how to set all the adjustments".  The problem is, that we can't tell them because their room and the rest of their equipment all comes into play. Just have to take the time to go through the steps. Sounds like you're getting to that point. Enjoy!

Carlman

Adding a sub
« Reply #5 on: 17 Aug 2004, 02:49 pm »
Mike, those are some good points... and since I've done photography for many years, I can relate to that point quite easily.

The one thing I did differently in this latest attempt at sub integration was using the built-in crossover.

A couple of weeks ago, I connected directly to the preamp outputs.  I needed a lot of volume to get the sub up to the level of the rest of my system.  So, I had to turn the sub amplifier's volume to about the 2/3rd's position to even hear it at low volumes.

Now that it's in the crossed-over situation, the sub amp volume is at 1/4th or so...  However, the volume knob on the preamp is a bit higher than usual, about the 11 o'clock position vs. the normal 9-10 o'clock.  This is all fine with me... I just think it indicates a fairly high sensitivity at the sub's amp and fairly low one on my 2-channel amp(s).  -I think this issue alone was one of my biggest issues.

I DEFINITELY need to do some real room response measuring.  It's silly how I've gone about this.  However, it's been an 'as time allowed' situation.  When I have an hour to burn, I can go play a little but then it's back to work... no time to go buy or research the situation much.

So, Tim... I'll definitely take you up on the Behringer.  I need to know something about what's happening.  I'll talk to you more about that sometime soon.

Thanks,
Carl

Carlman

Adding a sub
« Reply #6 on: 18 Aug 2004, 03:11 pm »
More findings...

Last night I connected my 100w AKSA into the mix.. Same setup as the Minimax... So, Preamp to Hypex to AKSA, using crossover in the Hypex.

The bass vanished, the midrange became etched, and the highs were too hot.  I was using some home-made IC's from Hypex to AKSA so, I tried replacing those with some Audience Conductor's.  That really helped midrange and highs... and the rhythm and pace were much better... all the reasons I like Audience IC's in general.

Anyway, what happened to the bass?  It was still set to the same position as before but I figured well... maybe since the AKSA is 100 instead of 8, I have the volume down too low for the same effect.  So, I cranked the sub to 1/2 and it sounded close but I just couldn't get an integrated sound out of it... I tried all sorts of crossover points, volumes, etc... and could never get the sub and speakers to blend as well as the 8w amp.  

Removing the sub from the preamp/AKSA combo, provided beautiful sound with no major issues.  The bass bloom was there but that was always there before.  (I've experienced these Usher's to have a bit of bloom in the lowest octave.)

Adding the Mini back into the equation was seamless.  All the controls went back to where they were and the added accuracy from the Audience cables made for a truly enjoyable listening experience.  The bass bloom is gone since I'm cutting that frequency from the Ushers and there seems to be an even lower octave presented musically and balanced with the rest of the presentation.  I can't tell I'm using a sub unless I turn it off.  It's very good in this arrangement.  

Anyway, I don't understand this but I thought I'd record it here.

The next experiment will be using the Europa's in the mix.

EDIT: the preamp has a 680 ohm output resistance, the AKSA has a 47kOhm input resistance... and the EE 8w amp has a 120kOhm input resistance... and the Hypex has a 15kOhm input resistance.

doug s.

  • Full Member
  • Posts: 6572
  • makin' music
Adding a sub
« Reply #7 on: 18 Aug 2004, 08:50 pm »
a few comments here...  1st, measurements *are* crucial to get a good starting point, imo...  it will save lotsa time in fine-tuning.  i like to use an equalizer/spectrum analyzer w/pink noise generator & mic to dial in the initial sub-to-monitor relationship.  then, tune to ear.  also, you will get far better results, imo, w/a hi-quality outboard x-over, than what's included in the sub amp.

re: not getting as good results w/one amp vs another, this is also not that unusual.  some speakers will react differently w/different electronics, in different set-ups.  again, using measurement dewices will get you much closer to flat, from the start.  also, perhaps, in your case, the amps have different phase?  

i know, that when experimenting w/different speakers in my system, in one case, (swan m1.2), i actually got better results w/my diminutive modded asl wave-8 8wpc amps, crossed over at 125hz, than w/my mesa baron, my normal amp.  and, normal x-over range w/other speakers is 50-70hz...  the swans had a mid-bass bump that was ameliorated by the leaner bass of the li'l waves, & the vmps larger subs are actually more lean & tight between 50hz-125hz than were the swans...  this was actually wisible on the spectrum analyzer...  the waves are down in output in the low end, & the swans midbass was a bit elevated...  and, of course, the wave's, at only 8wpc were happy to not have to deal w/any frequencies <125hz.

doug s.

JackD

  • Full Member
  • Posts: 1433
Adding a sub
« Reply #8 on: 18 Aug 2004, 10:04 pm »
Carl

Have you tried hooking the sub up using the recommended "REL" method.  From the speaker outputs on the amp to the speaker inputs on the sub.  You can use any low gauge speaker wire, Vandersteen supplies regular old Monster.  Set the sub at the lowest crossover point and work your way up. This is what Roy recommended to me with the Europas when I tried the other two Non-Vandersteen subs with the Europas.  I got the best results with these subs, with the sub placed as close to the center of the Europas as I could get it and at the lowest x-over setting.  This also worked with the same subs and the Reynaud Trentes and the Solioquy 5.0's.  

I agree with Doug that the external crossovers like the Marchand's are better, but also more expense. I don't think you will find a better midrange and up than the Europas for anywhere near the price, and I am counting the 3x more expensive Trentes.  You just need to get the sub blended in correctly.  Talk to Roy and see what he says.

ieales

Adding a sub
« Reply #9 on: 28 Aug 2004, 08:27 pm »
Something I've never  seen discussed in mating subs to mains is the enclosure type.

For my 2p, I would first try a ported sub with ported mains and sealed with sealed mains. No sense handicapping yourself from the start with [blazingly] fast mains and [relatively] lethargic sub. OR vice versa.

Read BETWEEN the lines on any reviews and / or forum posts. An endorsement from a 110db headbanger won't be much use if you're a 80db jazzer

Test gear can be an assistance, but if you go just for the numbers, look out! More than once, I've zeroed out what the test gear told me and started over by ear. Moving the test microphone as little as 6 inches can have a HUGE effect on the numbers. Microphones have no cranial capacity to adjust to make sense of what they measure. Most ears have an incredibly sophisticated signal processor between them. If they didn't, recorded music would be unlistenable.

Make sure any sub has a continuous phase control, 0 / 180 won't cut it unless you can move the sub several FEET.

Do
      Take your time
      Make small adjustments
      Listen to many music styles
      If Happy {
           Exit Do
           }
Loop

http://www.ielogical.com/audio.html#basement

Carlman

Adding a sub
« Reply #10 on: 28 Aug 2004, 09:40 pm »
Quote from: ieales

Do
Take your time
Make small adjustments
Listen to many music styles
If Happy {
Exit Do
}
Loop

Thanks for the instructive advice.  I got caught in an endless loop so I've started selling the sub in parts.  The amp is gone... I'll be selling the rest as interest occurs.

I have come to the realization I don't like subs (I've used so far).  One day I'll hear a good setup that has impact and detailed bass and seamlessly integrates with the rest of a system.  

I got some really good sound out of that sub but running my main speakers full range without a sub has better midbass... better in that the midbass has more impact and toneful bass.... The sub had deeper bass that rendered some things technically more accurate but was not a better musical experience.  A kick drum sounds more alive to me without a sub.... plucking a bass string has a better attack and decay.. the timing I think is my issue.  I didn't have an infinite phase adjustment but I DO have feet to play with.  I wouldn't care if the sub was a coffee table.  ;)

While the sub did sound awesome in some ways, having another device to tinker with in combination with the sonic trade-offs just wasn't for me.  

-C