advertisement


Loudspeakers and Bass Response

Isobarik said:
I demoed a pair of Glastonbury 2s and the bass was unbelievable ' felt it in my stomach' so purchased them. I borrowed the amp that I demoed them with a Audio Research valve amp, can't remember the model but I do remember it having quiet a lot of valves! They were totally bass light in my room, sited them in different positions all to no avail.
Click to expand...
I have Isobariks in a room about 14 x 14 with a 10 ceiling. Suspended wooden floor with a crawl space underneath. Carpeted, in fact I have a big throw on the wall behind where I sit to cut reflections. I have a friend who works for the BBC and is a total hifi buff, goes to all the shows. Builds his own speakers, amps etc. He said to me a few times and said again today that he's never heard another system with the bass impact and punch mine has, including all the hi-end stuff he's heard at Munich etc.

I don't see any reason why you shouldn't be able to achieve good bass in your room. It's big enough. It can only be a question of equipment and set up choices. I've had rooms with concrete and wooden floors, they are different and need different treatment but both can work.

You say MVV's room has a lot more space in it? Is it so packed with furniture that the speakers can't go where they need to and nothing has any hope of working?
 
Agree that it's likely the room.I had a similar problem. I did a quasi scientific test. Speakers in the kitchen really punch. This is a smaller room, closer listening position etc.
I move them into my main listening room with suspended wooden floor and it all disappears. Bass is uneven, boomy, and mids missing. Bought an amp with Dirac and it improved the sound immensely. I could finally see (and more importantly, understand) what was causing the problems.

Might be worth auditioning an amp with dirac from a dealer and see what it does for you. Not saying its a magic bullet, but you will at least get an idea of how your room behaves if nothing else!
 
Isobarik said:
Never really heard bass in my listening room mainly due to the construction of the room, wooden floor with a large cavity underneath.
Click to expand...
It is your room. Is the cavity underneath accessible? If so, pop yourself down there and you'll find that's where the bass is hiding.

I had a similarly sized room with my mum's granny flat underneath it at my old house. When I finally got around to measuring the room response with just an SPL meter and 1/3rd octave warble tones, I observed a fairly narrow dip of around 18dB centred at 80Hz. That is smack bang in the mid-bass spectrum, where weight and kick is located. Changing loudspeaker locations would make some, but not much difference. The best I could get was a -10dB dip, and that was achieved by locating the loudspeakers directly over where a steel beam was under-floor.

Short of pouring concrete to fill in the cavity, your next best bet is to strengthen the floor with additional beams to reduce flex.
 
James said:
It is your room. Is the cavity underneath accessible? If so, pop yourself down there and you'll find that's where the bass is hiding.

I had a similarly sized room with my mum's granny flat underneath it at my old house. When I finally got around to measuring the room response with just an SPL meter and 1/3rd octave warble tones, I observed a fairly narrow dip of around 18dB centred at 80Hz. That is smack bang in the mid-bass spectrum, where weight and kick is located. Changing loudspeaker locations would make some, but not much difference. The best I could get was a -10dB dip, and that was achieved by locating the loudspeakers directly over where a steel beam was under-floor.

Short of pouring concrete to fill in the cavity, your next best bet is to strengthen the floor with additional beams to reduce flex.
Click to expand...
Hi James,
Yes the cavity is accessible and I've been down a couple of times , there's about 14" of water down there, it fills the whole area! It's more like a a swimming pool!
I think I'll invest in a SPL meter to find out where the bass is disappearing.

Unfortunately the house is owned by a Housing Association so pouring down tons of concrete to fill the cavity won't be possible I'm afraid, but I would if I could. 😃.

I've tried mounting the speakers on Marble slabs and concrete slabs and it hasn't made a scrap of difference.

Used different floor spikes too.
Thank you James for you input, much appreciated.

I'll get myself a SPL meter and a wet suit too!😬
 
Last edited:
Mr Pig said:
I have Isobariks in a room about 14 x 14 with a 10 ceiling. Suspended wooden floor with a crawl space underneath. Carpeted, in fact I have a big throw on the wall behind where I sit to cut reflections. I have a friend who works for the BBC and is a total hifi buff, goes to all the shows. Builds his own speakers, amps etc. He said to me a few times and said again today that he's never heard another system with the bass impact and punch mine has, including all the hi-end stuff he's heard at Munich etc.

I don't see any reason why you shouldn't be able to achieve good bass in your room. It's big enough. It can only be a question of equipment and set up choices. I've had rooms with concrete and wooden floors, they are different and need different treatment but both can work.

You say MVV's room has a lot more space in it? Is it so packed with furniture that the speakers can't go where they need to and nothing has any hope of working?
Click to expand...
I'm pretty sure it's not my equipment Colin!
Sony TA-F700ES
Linn LP12
Young M2TECH DAC
Revox B77
Sony ES Minidisc
Dunlap Clarke Dreadnaught 500 power amp ' well respected by Mr Pass'
Naim 42.5
I sometimes use my Naim 42.5 along with this:


I sometimes use a Dunlap Clarke Dreadnaught Power amp now and again to keep it in working order ' the one shown on my avatar '

So I don't think it's my equipment. The cavity under my floor is filled with 14" to 16" of water, more like a swimming pool:cool:.

My room is not heavily furnished, just a normal living room.
I even went to just my hifi, a settee and bugger else to see if I could improve the bass response to no avail. Thank you for your advise though much appreciated.
 
Last edited:
Isobarik said:
Unfortunately the house is owned by a Housing Association so pouring down tons of concrete to fill the cavity won't be possible I'm afraid, but I would if I could.
Click to expand...
What is the surface under the water? If it is solid rock, the other option is to install posts between the floor beams and the ground in the cavity space to reduce or eliminate the floor flex. Do it one post at a time to see if it does enough to tune the dip out. As you don't appear to own the house, it is an easily reversible mod if the posts are held in place just by the weight of the floor, with a precisely cut length.

If the submerged surface is marsh, then all bets are off!
 
darrenyeats said:
No I mean to integrate sub(s) properly usually needs delay control, usually on the mains, and the only practical way to do this is with DSP.
Click to expand...
That's my experience, I ran dual subs the whole time I had the Lyngdorf amp with DSP. I found that I was unable to integrate them to my satisfaction without DSP even using the PEQ on the SVS subs, but then again I am a technophobe who is unable to use REW.
 
music fiend said:
If it's a high level connection and the subs are very close to the main speakers, I can't think of any reason for needing delay control.
Click to expand...

That's where i ended up, subs are outside the mains and a little bit closer to the listener, more or less in the corners which i thought shouldn't work but does.

Initially i was thinking about film use but they integrate so well that i use them all the time. 95% of the setup was placing and setting then RoomPerfect completed the job.

It's a very lossy room with glass and a suspended floor.
 
James said:
What is the surface under the water? If it is solid rock, the other option is to install posts between the floor beams and the ground in the cavity space to reduce or eliminate the floor flex. Do it one post at a time to see if it does enough to tune the dip out. As you don't appear to own the house, it is an easily reversible mod if the posts are held in place just by the weight of the floor, with a precisely cut length.

If the submerged surface is marsh, then all bets are off!
Click to expand...
It' just builders rubble from when the house was built
It's quiet nice though when I hear the waves crashing into rocks underneath! :) especially when I listen to Debussy's La Mer. :D.

I'll take your advice James and get myself a SPL meter to see what's going on.
 
Last edited:
I've had similar, moving from a series of houses with solid concrete floors (one '70s flat and two '40s/50s houses) to our current and forever home, which has a wooden suspended floor. Previous favourite speakers that I bought with me when we moved, were KEF Reference Three-Two worked supprisingly well in the old room despite being smaller. The new room had no end of problems, tried a mix of spikes, soundcare Superspikes and some Auralex Gramma pads, the latter helping quite a lot but still had a severe bass boom which caused parts of the floor and door to audibly vibrate. There is a ~350mm deep cavity under the floor, might be room to do some work on the joists/floorboards in the future but far more important work to be done on the house first!

Found the Yamaha NS1000M worked a lot better, and liked being up against the rear wall as a pretty good compromise. However baby arrived and system was relegated to background music so such large speakers are no longer required.


System by Robert Seymour, on Flickr


System by Robert Seymour, on Flickr


System by Robert Seymour, on Flickr
 
Hoopsontoast said:
I've had similar, moving from a series of houses with solid concrete floors (one '70s flat and two '40s/50s houses) to our current and forever home, which has a wooden suspended floor. Previous favourite speakers that I bought with me when we moved, were KEF Reference Three-Two worked supprisingly well in the old room despite being smaller. The new room had no end of problems, tried a mix of spikes, soundcare Superspikes and some Auralex Gramma pads, the latter helping quite a lot but still had a severe bass boom which caused parts of the floor and door to audibly vibrate. There is a ~350mm deep cavity under the floor, might be room to do some work on the joists/floorboards in the future but far more important work to be done on the house first!

Found the Yamaha NS1000M worked a lot better, and liked being up against the rear wall as a pretty good compromise. However baby arrived and system was relegated to background music so such large speakers are no longer required.


System by Robert Seymour, on Flickr


System by Robert Seymour, on Flickr


System by Robert Seymour, on Flickr
Click to expand...
I might try a pair of stand mounts instead of floor standers, something like a pair of ES 14's
Thank you for your input! Much appreciated.
 
Coming to think about it, I did once achieve bass,that was with a pair of ProAc 125's with a back firing port, perhaps the port was accentuating the bass frequencies?

You were right Ponty, I should have given them more time!
 
You must log in or register to reply here.


advertisement


Back
Top