Addicted to Fun and Learning
- Jun 9, 2019
I will tell you what I see and think with the caveat that I have a moderate understanding of the RT60 and decay curves and there are others that are far more sophisticated than I am. Working backwards:
So now that we know how your room is measuring, lets look at your speakers and what we can do with them:
- In looking at the waterfall, I am looking to see if there is any real unevenness in the decay times that could leads to the excess of energy we from about 500 hz up to about 2k hz when we look at your frequency response graphs. The if there is, it is your room causing the excess energy, not the speaker. What I see in your waterfall is a very even and consistent decay across that frequency range. The RT 60 range confirms that, showing decay times from 250-350 ms, which is a well dampened (actually slightly over dampened) room. This means the excess energy in that range is your speakers, not the room. It also means you should not add any dampening to the room, it will make it too dead.
- The Rt60 also shows you have a bit of ringing in the 120hz area (which isn't there on the waterfall) and the waterfall shows your room mode at 40hz with a long decay. It appears from it your room is relatively square. There is no reasonable room treatment that will fix this issue, we all have large modes in the bass, don't worry about it too much, this is where your room correction software is useful.
- Remember, unless there is something really off with the room, the speaker's voicing dominates the sound above the Schroeder frequency, the room below it. The Schroeder frequency in most rooms is about 200hz (it can be calculated with the room dimensions.
So looking at alternative speakers, her are my thoughts:
- We are fortunate, Stereophile has measured your Spendors so we have some good data on them: https://www.stereophile.com/content/spendor-a7-loudspeaker-measurements . I see a few things that stand out that I don't like in measuring them and would lead to them being less than optimal in your room:
- Depending on how your look at it, they either have a broad suckout from 100-600 hz or a broad plateau from 700-10,000 hz.
- Their bass is strange. Generally we will see a from a very slight to a broader bump centered at about 100hz in the stereophile measurements, see these examples:
- Your speakers don't have this bump. Rather they have a huge suckout from 150-200 hz and then a peak at 55hz. As a result their -10db point is about 30hz and at 40 hz they are only down a couple of db, which means they are going to really aggravate your room mode. They probably still aggravate it with an 80hz hp because of this weird response. Since you are using a Mini DSP, try 36db octave on them.
- Generally, when looking at an in room response, we like to see a 5-6 db overall drop from about 100hz to 10k. We have the opposite in your room, which is going to lead to a forward and thin sound, with a big fat boom at 40hz because of their strange bass response.
- Before you buy other speakers, give the following a try with your mini dsp:
- Change your high pass to 36db/oct at 80 hz.
- Add a -3db 1.0q filter at 1,200 hz.
- Add three high shelf filters, one at 215hz, one at 1000 hz, and one at 4642 hz, all -1.7db with a q of .5
- The foregoing filters should help with the broad midrange peak and add a bit of a house curve. Let us know how this sounds. It should help some, but your Spendors have inconsistent off axis response which will limit the effectiveness of using an EQ.
I know it is a lot to digest, with perhaps not the best explanations, but I hope this helps sum up what I see as the problems you are experiencing with your current speakers, how to try and correct them in the meantime, and what to look for in a replacement pair.
- Most floor standing speakers should work well in your room, especially when used with a crossover. The issue you having with your current speakers aggravating your bass mode appears to be due to their peaking close to your mode frequency. Even with a 24db octave filter at 80hz they still are putting out significant bass. Compare that to even a Revel F228be or Kef Reference 5, both of which have good strong bass, but not a peak at 50 hz and you will see that they have about 5-6 db less energy at 40 hz relative to the midrange (4 times less energy).
- I am a believer that even crossed over, your main speakers should, if possible, offer a relatively linear response to 1 octave below the crossover frequency. This means down to 40hz. This gives a more predicable transition from the mains to the subs. It also favors floor standing speakers over bookshelves.
- I would not get concerned about the BMR's extending down to 32hz. Their bass is highly dampened with a -3 db of 62hz and -10db of 35hz. Combined with your crossover, even counting room gain, and they should be at least 20db down at your room mode of 40hz. See Erin's measurements here: https://www.erinsaudiocorner.com/loudspeakers/philharmonic_bmr/
- If you look outside the Revel camp, you may be able to find better values in the UK. I would suggest checking out some KEFs, Elac and Dynaudio speakers also, all of which are engineering focused companies. Harbeth may also be a good choice as they are UK based. Also, the Wharfedale Linton Heritage come in walnut and could be a good fit.
- I would also suggest you consider the Salk Song 3 speakers. https://www.salksound.com/model.php?model=song3 Not sure what they would cost shipped to your door. I had a pair and they were very good sounding, transparent, and the tweeter sounded a bit sweeter and better than my Revels. The reason I didn't keep them was they had a very flat and dampened bass, where I like a bit of hump like the F208s have. For you, they could be a really good fit, plus you can get them made to exactly match your existing furniture.
Wow..... I hope you don't mind but I need so time to digest all this info!
I will say that you've hit the nail on the head with regards to how my Spendors interact with the room.
They are totally uncontrolled in the bass region and even my Anthem STR struggles to cope with it.
My Arcam with DIRAC before that couldn't deal with it either. It was too much for the EQ to handle and I always ended up dissatisfied with the end result.
I can't even play them "full range" without some form of EQ because the bass just dominates the room and literally vibrates the whole room.
It's ridiculous really.
They do sound good though, I will say that and I'll probably miss certain aspects of their sound signature but they really do have to go.
Would the fact that the next set of speakers will be placed in the same, not ideal location and make the new speakers sound the same with the same room issues??
I'll chew over what you've said and post again... Thank you so much for your valued input!!