BASS!....the infinite baffle thread

greetings all

i'll begin at the beginning

like many of you, bass is my religion.

not the cheap, boomy flappy stuff, but the real, deep extended business :JOEL:

genuine extended bass is just about the hardest thing for a hifi to acheive, so by the time your there all else should be perfect, no?

previously i've done the conventional and concentrated on the right source, amps and speakers, but after a while you have to start thinking 'outside the box' imho

the compromise is most evident with the speakers. there are many briliant transducers that can delight and enchant, but few that can REALLY plumb the depths and still be capable of true delicacy. i've enjoyed horns and transmission lines, but always suspected that someone truly comitted could do better....why not build the bass speaker into your house, using your entire house as the enclosure?
i began a thread on this forum, and so came my introduction to the 'cult of the infinitely baffled'.

here's what i'm up to:

in my listening room ceiling will be a nine square foot rectangular hole. above it, in the loft, will be a manifold covering the hole and open into it. all other sides are sealed, and facing each other on each long side will be two 18" drivers, four in total. this will be my infinitely baffled sub.

the IB will be the same distance from the listening position as the main speakers (alon phalanx, also open baffle), and midway between them. the sub will recieve only sub 40hz signal, probably crossing over at 36hz.

the bit that i'm currently stuck on is amplification.

the 'cult of the infinitely baffled' favour >700watts/driver, and are huge fans of the behringer europower pa amps rated at 3600 watts, but i'll be buggered if i'm having one of them in my system. however the cult also reckoned that my krell ksa 100 would be perfectly up to the job- but that's only got 100 watts.
so, being non-technical, that confused me a tad.
worse, the krell is now destined for other things so i need to get another/some more amps.

here's my question:

should i get someone to build me a solution

(chris bryant, built my power amp and is building me a pre-amp)

or should i just buy some current monster from the states?

(i'm thinking of passlabs specifically, maybe krell)

if we build something i guess we would most likely build one amp per driver, as chris favours building more lower-power amps than a single monster

my budget is about £2-2.5 grand for the bass amp(s), and i prefer s/h as i like more bang for my buck

so....

whadoyoureckon?


many thanks
gav

 

why dont you want the large Behringer?

''as much power as possible'' is a good starting point for a subwoofer IME

 

Gav,

What is your main source, vinyl or CD? In my experience the best bass is only found on vinyl so thats where l would start

Cheers Mondie

 

Get a PA power monster. Something like the Crown CTs 3000 is a bit up market from the Behringer. http://www.crownaudio.com/amp_htm/cts.htm

Separate amps per driver is good for main speakers as they can get different signals but each woofer in your MONO IB sub will be getting the same signal, so one big power amp is fine for driving all of the drivers.

You really won't hear any difference in quality from an affordable PA amp and some mega audiophile powerful amp, since it will only be working below 40Hz. In fact anything other than a highly powerful PA amp is likely to sound worse.

Any pictures?

 

Try MC2 Audio,
Amps of choice for driving huge rigs for Turbosound, Martin Audio and Funktion as well as actively driven Dynaudio, Tannoy and Quested studio monitoring.
The lightweight E series are excellent but the daddy is the MC1250 which is an extremely capable amp when driving multiple bass stacks.
The Behr...... are just toys in comparisson.

 

Is there much between the MC2 and Crown for sound quality? (using them on proper speakers)

 

I have been looking at implementing a similar system, possibly using modules from http://www.hypex.nl/

I have however been unable to find suitable drivers in Europe.
Which 18" versions are you intending to use ?

 

hi guys, many thanks for your replies

they aren't the most reliable (i've heard), and i've always seen them as a bit 'bargain basement'

but the crux of the issue is that in my (limited) hifi experience it has only been massive class A monsters that give the truly terrifying bass sound i crave, so i assumed that was what i required in a bass only amp?

i guess this approach stems from what i said in the intro, that true hifi bass is expensive and requires the best kit?

 

hello mondie,

i couldn't agree with you more

my main source is vinyl, i have a cranfield rock, excaliber arm and reson rica cartridge.

just recently bought my first cd player (yba cd1), so i'm fairly committed to vinyl

 

wotcha simon

this is the bit i need to get my head round.

i thought the class a lumps produce such lovely bass because of their audiophile design?

what i mean is, if bass was of no importance, i'd happily use a bow technologies wazoo amp, but demo'd next to an alchemist or krell it doesn't cut it in the sub-bass region, so from that i deduced it's that amount of on-tap welly that makes the big amps so big and expensive?

 

hello alphonso,

i had been planning to use these:
http://www.madisound.com/images/Aurasound18.jpg

however chris has some reservations, so everything's up for negotiation atm

 

i have to say the MC1250 looks perfect for my needs, as i prefer a non-switching amp

http://www.mc2-audio.co.uk/images/titles/mc1250.gif

i've e-mailed a price enquiry, anyone know how much they retail for?

do you think i would need more than one?

regards
gav

 

IME a definite yes, there is.
The MC2 (the range has a family character that is just plug and forget)is a far easier listen-dare I say it-more musically enjoyable, with better bass and smoother top end.
(Crown K2)The Crowns initially impress but soon start to wear you down-again just my opinion.

 

AH,I've just re read you post
4x18's you'd only need 1 MC but as others have said if just below 40hz any muscle amp should do it-just get one with good PA bass credentials.Look out for s/h MC's the T series are very good(T1500 would suit too) and can be had for £400-800 s/h depending on how lucky you are.

 

I think Tenson (and others) are right - go for the best high power studio amp you can - it's just perfect for a subwoofer.

High damping factor and plenty of power on tap... and a sub is where you really need that power.

Your american friends have the right idea IMO, I'd leave the audiophile gear for the rest of the hifi.

 

Interesting. How would the MC2 amps compare to muscle(ish) amps of the "audiophile" variety?

A thread I dug up here on audio asylum suggests well - with favourable comparisons against Chord and Nuforce for example.

The T1000 pushes out 300wpc into 8 ohms and the other specs look good too and comes in at less than £1k (new), seems like it could be a real bargain if the sound quality matches the specs.

Edit to say - this is in the context of a full range amp - not just for driving the bottom end - sorry of its a thread hi jack.

 

This is what you want dude.

http://www.labgruppen.com/plm/index.htm

Why can't domestic manufacturers be this adventurous, i.e combined amps and digital x-overs??

 

Probably a bit overkill Andy! But yes, very nice.

Forget about audiophile amps because even the 'powerful' ones are hardly powerful (300watts isn't really enough IMO). You want something with 1000watts or more. I wouldn't worry about class A or not, since it does not necessarily make a better amp. The reason the big Krell and so on sound better in the bass is mainly because of their stiff power supply.

You could try a pair of Hypex UCD700, one per pair of woofers to give 1400watts. But I'd just as soon go for the Crown I mentioned with 3000watts.

By the way, I would keep the amp in the same space as the woofers so you can have nice short speaker cable, it will keep resistance lower and give better damping factor. If you had the amp in the room below and had to run 6m plus of cable it may not be as good. Plus, you can easily get away with a switchmode PSU in the amp as any interference thrown out will be negligible when its in another room.

 

Gald you got the joke Simon...the new Lab amps are extremely sexy though.

 

but wouldn't his mean i'd have to have a 6m interconnect?
which is worse?