Martin Logan CLSIIz - adding more bass?


I have Martin Logan CLSIIz speakers, VTL-MB 125 mono block amps (RCA inputs only)and a Sony CDS-X7ESD CDP that is connected directly to my amps. I am thinking about adding a subwoofer and was wondering if anybody has any advice? My room is quite large (open floor plan) with a high slope ceiling in one part-like a loft. I don't know the volume but dimensions are about about 20 x 30ft with the highest part of the ceiling about 18ft. My budget is around $1000-1500USD and I only buy used! Thanks!
alexl9ba7
I have a similar system and room. Your goal should be stereo subwoofers, crossed over electronically at 100 hz or less 18db/oct or more. The larger the driver the better - 12" minimum. Taking incremental steps in that direction (use a single summed woofer at first) will get you there. For example, bryston or db systems xover, adcom 555 amp and HSU 1220 or 1225 woofer will stay within your budget. There are MANY other combinations possible, for example the Vandersteen.
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i'd suggest a pair of subs crossed over @ 60-70hz, w/a min of 24db/octave slope. i'd also suggest a pair of vmps larger subs. these are *awfully* hard to find used, but even brand-new, there's nothing that approaches 'em at anywhere near the price, even used. plus, their price includes direct shipping. most dealers will discount these at least 15%. pair these w/a decent x-over from db systems or marchand (or some hi-end used x-over), & a good used solid-state amp, & yule be happy. mebbe it'll be a bit more than $1500, but not by much, and at least yule be happy w/the results. i also buy mostly used, but the vmps were a no-brainer, & i've no desire to change (except to upgrade to their most recent drivers, but it's hard to imagine they could be faster/tighter than what i already have!)
i'd suggest a pair of subs crossed over @ 60-70hz, w/a min of 24db/octave slope. i'd also suggest a pair of vmps larger subs. these are *awfully* hard to find used, but even brand-new, there's nothing that approaches 'em at anywhere near the price, even used. plus, their price includes direct shipping. most dealers will discount these at least 15%. pair these w/a decent x-over from db systems or marchand (or some hi-end used x-over), & a good used solid-state amp, & yule be happy. mebbe it'll be a bit more than $1500, but not by much, and at least yule be happy w/the results. i also buy mostly used, but the vmps were a no-brainer, & i've no desire to change (except to upgrade to their most recent drivers, but it's hard to imagine they could be faster/tighter than what i already have!)
What about the REL Stadium? Most CLS owners I've corresponded with claim this is the sub to have.
Thanks for everyone's responses...what about the crossover. Should I used an electronic one or a passive one?
ELECTRONIC IS THE WAY TO GO. However.....you really need to find one that is transparent enough to let the system benefits from bi-amping to show thru. Otherwise you end up hardening the overall sound. After a LONG search for an outboard electronic x-over for use with my Apogees, I can recommend the HSU outboard electronic x-over and at $459, it is a steal. I recommend the stock x-over point of 90 HZ, but you can set it lower with plig in chips. It has a 24 DB per octave slope for the high pass section (your CLSs) and 24 DB per octave for the low pass section or an all pass output which allows you to pass a copy of the input signal to the sub or elsewhere. You will immediately notice : more dynamics, greater output, greater transparency & ease and a larger, better defined soundstage. Not bad for a $500 tweak.
I have the same speakers and recently purchased used the kinegistic sw800, the same subs reviewed by aboslute sound with the m-ls and deemed the "super system", or something to that effect, still experimenting but they are seemless without the booming effect; my experimenting is somewhat more complex because i am using a meridian 568 processor through which i'm setting the controls; i believe there is a demo pair for sale on audiogon; steven
Hi Alex1, I tend to agree with Jab on finance and powercord. Check it out carefully with others who are familiar with the rest of your gear. Hybridizing electrostatics with a sub is always tricky and expensive. MLogan CLS11z specs read 35~22kHz which is in fact a FULL range music speaker (unless you intend a HT purpose). My own MLogan Aerius' bass is ample in a small room although it's low limit is 40Hz. What interconnects are yours? I've read that MLogan eng. development were in collaboration with Monster cables. That history is important to the end user. Monster do have some very good hi-end cables recently, maybe worth to check it out. My Aerius and amps are using mid & hi-end Monsters. I know the bass is there because the sound is 3D! Another thing to check is the amp, some tube amps have a hump in the upper bass, so giving a FALSE perception of a "suck-out" of lower bass in a "neutral" speaker. Consult other VTL owners about that. I sold my ARC VT60SE because of that phenomenon, but I'm not sure about your amp,Something you have to check. If the suggested cables work, you would have enough money left (from your budget)to buy another stack of audiophile music. Regards, Phil.
re: x-over, definitely go active. i don't think you'll touch the quality of db systems or marchand electronics at anywhere near their prices. use at least a 24db/octave slope w/electrostatics.
Hi [email protected] - Please post your progress in your checking, I'm curious for your results. Sorry our responses might have caused you much travel & again more time for research. Warm Regards.
Spend the money on larger amplifiers - you'll get far more satisfaction for the expenditure. I have the same speaker and recommend a minimun of 225 watts (I'm using the VTL 450's). Also have the REL Storm III and have been very dissatisfied with its performance with the CLS.
hello I agree with Mig007 the kenergetics 800 system was invented by Tony DiChiro specifically for his pair of his Martin Logan CLS speakers. The key is the woofer size anything bigger than 10in isn't quick enough to match the eloctrostatic panels quickness but requires about 10 woofers to accomplish enough bass output. The crossover is very transparent also. A good high current at low impedance amplifier is required a Levinson 23.5 works really well.
You might consider a pair of Entec subs as well. The LF20s were originally over $6K but might be had in your budget. Check here at Audiogon.

Alternatively, the Celestion System 6000 gave great sound with my CLS, but doesn't have the ultimate volume of the the Entecs.
I owned a pair of cls2z and i used a paridign servo 15 with great results now I use a martin logan desent sub with my oydesseys the sub is so mind blowing !