And here it is, the 340SE2!!!

Thank you all for the replies. I ended up pulling the trigger on the 340SE2's last night for the L/R and a horizontal oriented 340SE2 for the center with stands. I'm sure they are going to sound awesome! Looking forward to them Dave.

I'm going to make sure and follow up on the sound when I receive them. Too many times I see people go for audio advice on reddit or AVS forums and they never follow back up! With the SE2s being relatively new I couldn't find much feedback on them versus the old design from years ago, so I hope to spread some positivity towards these mini towers.

In my current setup with the CMT-340 SE2s there is a dip I measure in my in-room response between 100-200Hz. I have had this issue in multiple rooms with different speakers and I believe it is caused by floor bounce. With different stand heights and bookshelf speaker sizes the dip ends up in a slightly different location or severity but it is always there. Multiple subwoofers help to smooth out the frequency response below 80Hz but they don't do anything above that crossover point of course. I am really enjoying my current system but I can't help but feel like a little bit of mid-bass punch is missing, especially when I look at the measurements.

I have read that tower speakers do not have this issue or at least have it to a lesser extent. This is because most towers have multiple woofers handling bass and those woofers are at multiple heights. So while there are still floor-bounce nulls, they are spread out over multiple frequencies and one woofers null frequency will be filled by the others to result in a flatter frequency response. Much like multiple subwoofers but in the mid-bass region rather than sub-bass. I have also read about people using small 8" subwoofers for mid-bass from say 50Hz - 150Hz to bridge the gap between their subwoofers and monitors. The theory is that the small subs have a higher quality mid-bass than even a 6" mid-woofer but I believe the fact that the 8" sub sits on the floor is a large part of the benefit since it significantly reduces floor bounce.

Now currently I do own a couple of 8" DIY subs I could use to supplement my system but what I don't have is floor space to place them. They would have to sit on top of my 12" subs which would not be ideal for sound or appearances as far as I'm concerned. What would look great, and I wish I had ordered, is the TP-24 Pedestal stands. I like how my CMT-340s look on my current steel stands but if they were sitting on top of a pedestal full of mid-bass drivers that would look even better. So I'm thinking of possibly buying the TP-24 stands and modifying them to be mid-bass stands, although I doubt their construction would lend themselves to that without significant reinforcement. I was also considering purchasing some used CMT-340s and using them just as mid-bass stands, with an active crossover of course.

So I was wondering Dave, do these seem like bad ideas? Would the TP-24 stand be a good basis for modification into this sort of thing? Have you ever considered selling such a stand for turning these mini-towers into full floor standing towers?

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Originally Posted by TimW

In my current setup with the CMT-340 SE2s there is a dip I measure in my in-room response between 100-200Hz. I have had this issue in multiple rooms with different speakers and I believe it is caused by floor bounce. With different stand heights and bookshelf speaker sizes the dip ends up in a slightly different location or severity but it is always there. Multiple subwoofers help to smooth out the frequency response below 80Hz but they don't do anything above that crossover point of course. I am really enjoying my current system but I can't help but feel like a little bit of mid-bass punch is missing, especially when I look at the measurements.

I have read that tower speakers do not have this issue or at least have it to a lesser extent. This is because most towers have multiple woofers handling bass and those woofers are at multiple heights. So while there are still floor-bounce nulls, they are spread out over multiple frequencies and one woofers null frequency will be filled by the others to result in a flatter frequency response. Much like multiple subwoofers but in the mid-bass region rather than sub-bass. I have also read about people using small 8" subwoofers for mid-bass from say 50Hz - 150Hz to bridge the gap between their subwoofers and monitors. The theory is that the small subs have a higher quality mid-bass than even a 6" mid-woofer but I believe the fact that the 8" sub sits on the floor is a large part of the benefit since it significantly reduces floor bounce.

Now currently I do own a couple of 8" DIY subs I could use to supplement my system but what I don't have is floor space to place them. They would have to sit on top of my 12" subs which would not be ideal for sound or appearances as far as I'm concerned. What would look great, and I wish I had ordered, is the TP-24 Pedestal stands. I like how my CMT-340s look on my current steel stands but if they were sitting on top of a pedestal full of mid-bass drivers that would look even better. So I'm thinking of possibly buying the TP-24 stands and modifying them to be mid-bass stands, although I doubt their construction would lend themselves to that without significant reinforcement. I was also considering purchasing some used CMT-340s and using them just as mid-bass stands, with an active crossover of course.

So I was wondering Dave, do these seem like bad ideas? Would the TP-24 stand be a good basis for modification into this sort of thing? Have you ever considered selling such a stand for turning these mini-towers into full floor standing towers?

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I think they make a huge difference, I did experiment with a little bit of them and to fill in some clunking cat litter (about 50-60%) and got great results.. Later I mounted them on their cones and spikes.. No complaints any more.. But got lot of help from the forums here.. This is an awesome place to be..

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Originally Posted by ksr_sundar

I think they make a huge difference, I did experiment with a little bit of them and to fill in some clunking cat litter (about 50-60%) and got great results.. Later I mounted them on their cones and spikes.. No complaints any more.. But got lot of help from the forums here.. This is an awesome place to be..

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You can go to Home Depot and get clean/dry playground sand for the stands. Less expensive that cat litter.

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Originally Posted by curtis

You can go to Home Depot and get clean/dry playground sand for the stands. Less expensive that cat litter.

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Same fill percentage with sand? 50-60% ?

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Originally Posted by TimW

In my current setup with the CMT-340 SE2s there is a dip I measure in my in-room response between 100-200Hz.

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You are on the right track, try googling "flanking subs" for lots of info on smoothing response in the transition area.

I'm not sure how cat litter and sand got into this or help with floor bounce :D ....

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Originally Posted by bac2010

Same fill percentage with sand? 50-60% ?

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How did you get that fill percentage to begin with?

The sand/litter reduces the resonance of the stands (which is minimal anyways), but most of all it stabilizes making them hard to move/knock over. What kind of flooring do you have?

@rvsixer is right in implying that the stands wouldn't help with floor bounce.

I got new stands recently for my speakers. The mono price ones that look like Pangea stands. I got sand from Home Depot to fill them up. But it was slightly damp and wouldn’t poor smoothly into the stands. So I had to put the sand in the oven for a bit and bake it to get the moisture out!

Thank you! I was not sure if this was a common practice, nice to know it has a name. Even among people who adjust their system based on measurements it doesn't seem to be common. I found some of Wayne Parham's (of Pi speakers) posts about it and what I am thinking of doing he refers to as helper woofers or a 'detached 2.5 way.' Practically the same thing as flanking subs but using smaller woofer subs that can play up into the low midrange. I could use my DIY 8" subs for this (RSS210HF-4) but I can't really place them the way Wayne recommends due to floor space limitations.

Now what I am thinking of doing is taking the TP-24 stands, sealing them, installing a couple of woofers in each, and adding some stuffing. I read they are made of only 1/2" thick mdf but maybe with some simple square dowl bracing they will be stiff enough. I have a pair of Peerless HDS-835025 woofers that look like they would work well in that size sealed enclosure.

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Originally Posted by curtis

How did you get that fill percentage to begin with?

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Was repeating what ksr_sundar had used for fill percentage (in previous post). Floor is carpet and I added spikes that came with the stands. If there is no compelling need to add fill since resonance reduction is minimal then I'll wait. 340SE2's sound great as is.