Depth i Low Pass Filter Question

[Brad225]

I just purchased 2 Depth i's to probably replace my Vandersteen 2w's & M5 High Pass Filters.

The first thing that surprised me is their small size compared to me Vandersteens. Both have 3 8" drivers but the configuration of the drivers in the Depth allow for it to be much more compact. Second thing is that is one wimpy looking power cord. Not to say it is not the proper size or won't do the job adequately but it looks like I should be running a lamp or calculator with it.

The build quality of the subs is very good. Everything fits together well and the black finish with grain exposed looks great.

While reading the manual it seemed strange that ML suggests for its subs a starting point for the Low Pass Filter is 70% of the full range mains being used. Wouldn't that leave a big void in the frequency range and make blending the 2 speakers a problem?
Do you run your sub with RCA cable from your preamp or speaker cable from your poweramp?

Any thoughts on this would be appreciated.

I will probably have more questions for those of you that use one or more ML subs as I put them to work with my CLSIIz's.

Thanks

 

[Jungle Jack]

Hello,
Congrats on your acquisition of dual Depth i's. I certainly see your point about the recommended initial crossover point. I suppose you can try the recommended settings with test sweeps and go from there. I would highly recommend giving them a call as ML's Customer Service is outstanding. Also, I would do a search here on your subs as there are many posts discussing optimization. Especially with CLS IIz's.

I use a single Depth in a 5.1 Martin Logan System. Currently, I only have it configured in multichannel. However, it can be configured simultaneously for 2 channel and HT.
Cheers,
ML

 

[roberto]

I just purchased 2 Depth i's to probably replace my Vandersteen 2w's & M5 High Pass Filters.

The first thing that surprised me is their small size compared to me Vandersteens. Both have 3 8" drivers but the configuration of the drivers in the Depth allow for it to be much more compact. Second thing is that is one wimpy looking power cord. Not to say it is not the proper size or won't do the job adequately but it looks like I should be running a lamp or calculator with it.

The build quality of the subs is very good. Everything fits together well and the black finish with grain exposed looks great.

While reading the manual it seemed strange that ML suggests for its subs a starting point for the Low Pass Filter is 70% of the full range mains being used. Wouldn't that leave a big void in the frequency range and make blending the 2 speakers a problem?
Do you run your sub with RCA cable from your preamp or speaker cable from your poweramp?

Any thoughts on this would be appreciated.

I will probably have more questions for those of you that use one or more ML subs as I put them to work with my CLSIIz's.

Thanks

Hola...I am going to be nailled here, because I do love the bass that I have in my CLSIIZ, What I am doing, is without any filter them, and playing the music that you love most, just increase the level of the sub in a such way that you say..."there"...just tinny level at the bottom super low notes is needed in my room. Too much bass spoils my truly 3D that I have. It depends a lot of the type of music you like...happy listening,
Roberto.

 

[Brad225]

I finally had time to call ML today and spoke with Scotty one of the engineers. I explained the question I had about the set up suggestion in the manual that I have included below.
-----------------
(from ML Depth i manual)
As a general rule the Low Pass Filter should be set at the option approximately equal to (or below) 70% of your main speaker’s lowest frequency response.
Example: The Martin Logan Vista’s lowest frequency response is 43Hz. 70% of 43Hz equals 30.1, so you should set the Depth i’s low pass filter to 30Hz.
Remember, this is a general rule. We advise that once you
try the recommended setting using the formula above, you
should try the surrounding settings to see which sounds best.
------------------
He said that you should set the Low Pass Filter to 70% of the low frequency of your main speakers so there would be no gap in the frequency spectrum but an overlap.
So based on that, my CLS's it would be crossed over at 30% above the 35Hz of their lowest frequency. That would be a crossover point of about 42.8Hz if I figured it right.

Am I miss reading the manual with regards to my thinking they have said to set up their subs with a gap in the coverage of speakers.

 

[Jeff Zaret]

Brad,
I have my Depth set at 45 and I would for most things it is just fine. Remember you do not want to be able to localize the sub. In other words, you do not want to be able be able pick out the sub only that the bass frequencies are there.

Jeff

 

[Craig]

I finally had time to call ML today and spoke with Scotty one of the engineers. I explained the question I had about the set up suggestion in the manual that I have included below.
-----------------
(from ML Depth i manual)
As a general rule the Low Pass Filter should be set at the option approximately equal to (or below) 70% of your main speaker’s lowest frequency response.
Example: The Martin Logan Vista’s lowest frequency response is 43Hz. 70% of 43Hz equals 30.1, so you should set the Depth i’s low pass filter to 30Hz.
Remember, this is a general rule. We advise that once you
try the recommended setting using the formula above, you
should try the surrounding settings to see which sounds best.
------------------
He said that you should set the Low Pass Filter to 70% of the low frequency of your main speakers so there would be no gap in the frequency spectrum but an overlap.
So based on that, my CLS's it would be crossed over at 30% above the 35Hz of their lowest frequency. That would be a crossover point of about 42.8Hz if I figured it right.

Am I miss reading the manual with regards to my thinking they have said to set up their subs with a gap in the coverage of speakers.

According to their instructions it would leave a void. I suspect that most main speakers actually play a little lower in frequency than the published specs would indicate. I did some ad-hoc testing with Radio Shack meter and was suprised to hear and see the speakers playing bass at lower freqs than advertised. Also, my Descent I sounds fine with the low pass crossover set at 35-45Hz. The CLX setting on this sub is at 30Hz and we know the CLX isn't rated that low.

Could it be that a frequency void between the sub and mains is only on paper but doesn't really exist in practice?

I would take Roberto's advice and "Trust your ears".

 

[SteveInNC]

Keep in mind that the filter is not likely to roll off suddenly like a cliff. It will slope down towards the higher frequencies, just as the mains bass drivers roll off towards the lower fequencies. These two curves will overlap, resulting in a moderate bridging/reinforcing effect through that range.