Rega RS5 Bass or Lack Of

[Jsmith]

For some time I have felt that my speakers are a little lacking in the bottom end. I purchased an RTA application for my iPad and an external omni directional microphone trying to validate my gut feelings. Running a pink noise test through I find that I get a significant drop starting at around 200. The data looks like this:

 

Freq db

2000 46

1500 46

1000 47

500 45

400 45

300 45

200 40

100 32

75 30

50 24

45 23

30 22

25 18

 

My room is 12’ x 12’. I have bass traps in the corners behind the speakers and panels at the first reflection point and behind my listening seat.

 

While running the pink noise and RTA I tried moving the RTA up and down, forward and back. I have also tried moving the speakers closer and further form the back and side walls. All of this only made very minor adjustments. The best I could get was the RTA dead center between the two speakers and this was only a minimal improvement.

 

So my question is, is there anything more I should try or is this potentially a limitation of the speaker? Before spending money on new speakers or a pair of subs I want to try anything I can.

 

Setup:

Auraliti PK90

Rega DAC

Naim Nait XS

[mwheelerk]

Have you tried removing the bass traps and comparing the readings with and without? I would look at all variables before spending money on other speakers.

[Jsmith]

I setup the pink noise on loop and pulled the RTA. I took measurements with the corner bass traps in and out. Removing them did increase the bass but at most it was around 2dB which I believe correlates to about a 15% increase in sound.

 

Between 250 Hz and above and 125 Hz and below there is about an 11dB difference on average. I think this is around 230% louder.

 

This to me says the bass traps make a diffence but even with them removed there is still a gap in the low end starting around 200 Hz and down.

 

Other thoughts?

[mwheelerk]

You may have already done it but check the basics. Verify the speakers are properly connected in phase. If possible run your test with only one speaker connected at a time and compare results for significant differences.

[mwheelerk]

Where are these placed in the room in relationship to side and rear walls? I have read that because of the front firing port these can literally be placed against the rear wall so moving them back in the room may help. Additionally have you experimented with the side mounted bass to the inside versus the outside?

[jackfish]

A 7 inch driver in a bass-reflex loading has a hard time providing at least that "next half-octave" lower that all reviewers have asked for from this loudspeaker. The RS7 is a little better with its transmission line loading.

 

In that room a single Rythmik F12 will work wonders for your missing bass program material. Also try this Cardas Audio

[Jsmith]

I unplugged each speaker one at a time and took measurements. It did drop roughly 3dB with only one speaker.

 

I have tried to play around with speaker placement. Right now the speakers are 8.5 inches from the back wall. I have them on glides so I did try to slide them all over with the pink noise and RTA going. Really this provided very little measurable or noticeable difference.

 

I switched them out so the side woofer was firing out rather than in. This yielded roughly 1dB in their current placement and almost 2dB when moved within inches of the side wall. I could swap them out for this to get a slight increase, but I have found this has a pretty negative effect on the imaging and sound stage. Rather than the music being more centered and in front it pulls it out to the speakers and draws more attention to the speaker themselves.

 

I will play around with the Cardas golden ratio a little more as it takes some time with measurements and location.

 

Can you explain the difference between bass-relfex and transmission line?

[Jsmith]

Just as a side note, I listen to a lot of heavy metal music. I did some research and many of the bands I like (e.g. Fear Factory, Meshuggah) use down tuned guitars. I am no musician or expert but based on some research it looks like they start at A which is 110 Hz and go down from there. If this is the case, then it would seem that much of the music in what I listen to is well in the range of where my system has dropped off. And if you like heavy metal you know that it should carry weight and I feel that is what is missing.

[jackfish]

Can you explain the difference between bass-relfex and transmission line?

 

The difference between a bass reflex enclosure and transmission line (TL) enclosure is that the bass reflex uses the Helmholtz resonance, but on the other hand TL employs air column resonance at quarter wavelength, and is damped substantially with acoustic stuffing. The bass reflex enclosure seldom uses as much stuffing material for damping as a TL. While it is less efficient than a bass reflex, the transmission line can accentuate lower frequency resonance from a given driver.

 

Bass reflex - Wikipedia, the free encyclopedia

 

Loudspeaker enclosure - Wikipedia, the free encyclopedia

[mayhem13]

Unless Rega really goofed when designing the RS5 (down 22db@50hz!!!!) something is wrong with either your measurement or your integrated. If your measurements are correct, it looks like a 2nd order High pass filter slope centered at 100hz or so. If anything, a small room like yours should be reinforcing the bottom end...which isn't happening apparently. Sadly Rega doesn't post an anechoic F3 or F10 ( shame on them!) but let's see what might be happening with the Fc of the Rega's. Plug or block the ports and see what happens to the output from 100-200hz. If it goes up substantially in that range, it may be that Rega employed a very low Fc or tuning freq by design which will look like a 2nd order filter from the crossover point to the mid on down. I'd also call Rega's tech dept and ask them if or how much baffle step compensation is used in the crossover. If no BSC, that could account for losses of as much as 6db from 100-800 hz as well. If No BSC was used, the speaker was intended to be placed close to boundaries......very close actually.

 

Bottom line....your room isn't the problem if your measurements are accurate. It's either the speakers or the Naim.

[Jsmith]

I tried plugging the ports and overall the bass fell off.

 

I wanted to figure this out, so I figured before I dump money on new stereo equipment it might be worth $10 for a new iPad app. I purchased an RTA app from Studio Six where I had been using one from another company call Octave. This time I was presented with the exact opposite findings. The new app showed relatively flat with a spike in the low end.

 

So all of this may be the result of misinformation from the apps. I was hoping that with an external mic these apps would be fairly accurate and a useful tool. I think in the end they may still be a bit flawed, or maybe it is me.

 

I still wish my music had a bit more weight to it, but that might be a personal preference and not what is truly in the recording.

 

Thanks to everyone for their replies and help.

[Jsmith]

I thought I would come back and close the loop on this topic. I went to the dealer and auditioned a pair of Linn Majik 140 towers. The Linn's had more bass than the Rega's and overall sounded better. About what i would expect for close to double the price

 

Overall i was still really happy woth the sounds of the Rega's, but wanted more low end. Even the Linn's were lacking that chest thump I was looking for.

 

We put the Rega's back into the room and added a REL R-328. Suddenly the music nailed it. Lars from Mettalica's double bass had the same punch you get at a live show. NIN's computer bass had a real deep tightness. I could easily here the low detail in Enya's Watermark.

 

After a couple of weeks of listening I am very happy with my choice. It might not be as "technically" accurate some other paths I could have gone down, but it sounds exactly how i want it to.

[jackfish]

Nothing wrong with a good subwoofer well implemented.