where's my bass gone?

Hello everyone, sorry to make my first post a question - but here it is:

I have:

Meridian 588 CD
Linn Axis/Akito/Dynavector 10x MkII/Trichord Dino +
Meridian 501 Pre
Meridian 557 Power
Cyrus CLS70s bolted to the dedicated stands (sand filled!)

The sound seems really sucked out in the bass region. I don't know what has changed - if anything. It seems unlikely that it sounded like this when I auditioned the various bits of kit (I've had the system in its current form for a few years), but recently a friend came round and we were playing some Cds, when he commented "is something broken? There doesn't seem to be any bass?"

I had got used to the sound. I'm not a big bass freak, but it does seem very lean. I aslo run, via the second set of outs from the pre, an Alchemist Odin power amp driving an old pair of Wharfdale delta 30s in the kitchen. We spent some time walking between my study and the kitchen, and concluded that there was more bass in the kitchen, by a reasonable margin.

I've tried swapping the power amps, and the Alchemist definitely has a warmer balance compared to the Meridian, but it doesn't explain the big difference. Likewise the Linn TT is a bit warmer or more bassy than the Meridian CD. It seems that it must be down to the speakers - I've checked the phasing, I've tried moving them closer to the wall, but nothing seems to make that much difference.

Any suggestions?

Regards,

73C.

 

See if you can get hold of a test CD from your nearest audio store or maybe fro another user on here.

I use the Lasertrack CD which has 100 tracks of useful audio setup/test procedures. You can check phase, channel balance and all frequencies including a full frequency sweep of your speakers (individually and as a stereo pair).

Have you changed anything in the listening room at all recently?

 

Has your system always been like this or is it a new development? Has it always been in the same room?

If it has always been in the same room and place then it sounds like a room issue. Reflected waves from the walls cancelling out the bass from the speakers.

Try moving the speakers right in to the corners of the room. Let us know if that brings you some bass.

 

We moved house three years ago - in the previous place I had it in the living room, which was a long rectangle - this room is smaller and squarer. It's hard to try and remember objectively what anything used to sound like. I didn't use the system much after we fist moved (building works were going on) so there wasn't much direct comparison.

I've put the speakers into the corners and toed them in - there's definitely a bit of bass re-enforcement but it's a slightly muddy. The sound is still dominated by a rather bright treble. It seems to sound a bit like a rather high quality transistor radio.

Perhaps the test disc would help to put more objectivity into proceedings.

Thanks for the ideas.

 

Have you tried taking them off the stands. Sand sometimes sucks a lot of the bass away. What's the floor made of. Have you tried swapping them with the Wharfedales, did you get more bass then?
You need to try different speakers in the same room, the problem would appear to be there, if you still have no bass with the different speakers you almost certainly have a room issue.
There's a really good article here along with a formula to work out one ideal speaker placing try it and see how it works be warned there are some awful typo's in the article.
http://www.audiophilecandy.com/news2.asp?article=12&type=info
Let us know how you get on

 

what are the dimensions of your room and where are the speakers placed?

 

I haven't tried them off the stands - only other place to put them would be the floor. I guess I could try that.

The room is approx. 13' x 12'. The speakers are across the smaller side of the room - previously they were about 5' apart, and 18" off the wall. Now they are pushed into the corners, about 8" off either wall.

The floor is wooden (floorboards) suspended, with carpet over it.

it's a bit difficult to connect the wharfdales up in here as they only have those little clips for bell wire instead of proper binding posts, but I suppose it would be worth rigging something up to see how they sound. They were only £70, back in the '80s.

 

some stats and stuff on the cyrus here

http://www.hifichoice.co.uk/review_print.asp?ID=1098

 

I thought they were reasonably large speakers... its no surprise you have no bass when they roll-off sharply below 70Hz. You need a sub or more bass capable speakers.

 

That won't make the difference between them and the Wharfedales, I bet they roll off about there as well. You need to try some other speakers in that room that's where you'll find the answers

 

Hmm yes, got to try those Wharfedales in the other room.

I would suspect that being in the kitchen where there are lots of hard surfaces, the Wharfedales are getting lots of bass boom. So it would be more like something 'wrong' with the Wharfedale system than the Cyrus.

If this is the case and in the main room the Wharfedales sound bass light then you probably need to go to my previous comment.

Got to be empirical I think.

On the other hand if you like it, who cares?

 

I apologise if this is stating the obvious but did you check the absolute phase or the relative phase of the speakers?

If the speakers were out of phase relative to one another the bass would be diminished. Have you tried changing the phase of one speaker only?

Oh, and welcome to the forum.

Cheers
Steve

 

I read the hifi choice review with some puzzlement.

I couldn't work out whether they were saying that the bass goes to 70hz, or whether they were saying that this is what the port has been tuned to. It was ambiguous and could be taken either way I thought.

Anyway, regardless, perhaps a sub would be an easy fix. Technobear is selling his REL in the classifieds.

 

Your main issue is likely to be that the room dimensions suggest a broad and deep suckout between 70hz and 100hz. This will make the speakers sound a lot more bass light than they really are.

The speakers will appear to roll off at 100hz, whereas in most rooms with room gain, the Cyrus will have audible output to around 50hz. A loss of a whole octave of bass in effect.

Whilst experimentation with positioning will minimise this issue, try the speakers about 54cm from the rear wall, subwoofer augmentation is likely to be neccessary to counter the room's effects,

 

Yes, I think adding a sub might be the way forward. When the speakers were demoed, I got them to hook up a sub to see what extra depth was added. I seem to remember that it was a smaller REL Q series - I didn't end up buying it at the time.

The Cyrus were about the least bassy speakers I listened to during the demo, but they were also the fastest. I had intended to buy PMC FB1s, but these were really boomy. The Cyrus definitely didn't sound as bass light at the time of the demo as they do here - I can't imagine I would have bought them if they had.

When I get a minute I'll try some other speakers in this room to see what gives there.

Thanks again.

 

Did you check that you do not have your speakers wired out of phase?

 

I've tried switching one of the LF speaker connections (they are bi-wired) - this made the sound worse. How do I go about checking "absolue phase"?

 

To change the absolute phase you switch the positive and the negative terminals to both speakers. This will make little or no difference to the bass response and any differences at all will be subtle.

The best way to check the individual phase is to place the two speakers next to each other (facing you) and switch to mono. If you can't do this via the amp you can bridge the two positive terminals together with a length of wire. However, even in stereo you should hear the difference. If the speakers are out of phase the bass from one will cancel the bass from the other; if they're in phase the bass will sum. If the two speakers are next to each other there should be an easily identifiable difference as you alter the positive and negative connections to one speaker only.

You should switch the amp off before you switch the connections.

I hope this helps
Steve

 

Is everything connected proper like?