I've been tempted to try Broadway Limited's "Rolling thunder" on the cheap--just get the receiver (about $75) to use with a non-BLI subwoofer. My question: BLI's "official" subwoofer allows the low pass frequency to be set anywhere from 50 to 250Hz. The instruction manual recommends 200Hz. My alternative subwoofer would top out the low pass frequency at about 150Hz. Would I likely miss much, if anything, without letting higher frequencies through to the subwoofer (as BLI recommends)? I assume BLI opts for a higher frequency to capture some of the higher bass/lower middle sounds that on-board speakers also don't handle well, though perhaps at the cost of introducing more detectable localization of the sound source. Anyway, I'm wondering if anyone has tried this, what the results might be, and what impact different low pass frequency cut-offs might have. Thanks very much.
I keep meaning to answer this, but find my answers are wonky. It's been too long since I was involved in effective subwoofers -- the last one I had a hand in making was an adaptation of a Bud Fried 'everything but the wood' coffee-table design with KEF139 flat-plate drivers, which was clean down to pretty low audio frequency but would start to blare if you fed it ... well, anything approaching 150Hz; I can't imagine what it would do fed a complex waveform with components up to 250Hz.
I get the impression the "Rolling Thunder" system is like the 'infrasonic' feature of the THX theatre systems (or most of your friendly neighborhood woman-hunting automobile BASS enthusiasts' rides if you're in an 'urban' area : the output is to produce the thunderous rumble, not fill in the 'lows' the tiny onboard speaker can't produce. (In that sense I'd expect '250Hz' to be market window-dressing, not a useful feature in any particularly meaningful sense, especially for people who can discriminate directionality or imaging in the 150 to 250Hz range...)
There are people here who know the answers, or at least have firsthand experience with the BLI stuff, and we'll wait for them.
I have the Rollig Thunder System, but removed it because I didn't even come close to liking the system. I wish it worked, it would be great, but for me it was far from acceptable.
In all fairness to BLI, I used my own 15" Atlantic Technology Sub-Woofer. In addtion, I put a multi-band graphic equalizer on the input. I did that as I wanted the absolute maximum of control to try and get it to work well. I never got close.
I believe there are two major issues. One is that the gap between the engine audio and the sub are too great. You end up with a bunch of missing frequencies. They sound very separated from each other, not any sort of a blend.
The other issue is sound placement. Granted, BLI's comment that the low base notes are non-directional is considered a valid statement. In practice on my 15' x 25' layout, I never got to the point of acceptablility in that regard.
The third problem I encountered is that with the receiver in the middle of the room, I lost pick up strength from the engine rather rapidly.
To be fully fair with BLI, I need to point out again that I wasn't using their package (their Sub), I was using my own. I don't know if there would have been a difference or not.
I love BLI for their other product. I have a number of BLI engines including several Big Boys. BLI is my first choice for the serious product, so my comments are not biased, only a description of my reaction to this specific product.
It would be great if you got some reaction from users of the BLI factory packaged system. It might be different.
Deane Johnson I believe there are two major issues. One is that the gap between the engine audio and the sub are too great. You end up with a bunch of missing frequencies. They sound very separated from each other, not any sort of a blend.
Thanks, that's exactly what my concern is. The subwoofer in the full BLI Rolling Thunder package supposedly goes up to 250Hz, according the documentation. So in theory it could get closer to the middle range than many other low priced subwoofers without missing [as many] frequencies. (For example, TCS claims its High Bass WOW Speaker goes down to 250Hz--the top end of the BLI subwoofer. But other on-board speakers I've seen only claim to go down to 300 to 500Hz.) Maybe this is why I haven't seen the "missing frequencies" complaint in reviews of the entire Rolling Thunder system. Or maybe those reviewers just weren't listening closely....
Thanks again.
SpringStreet, I have installed one TCS WowSound module in a Athearn steam engine. I used the TCS baffle with the output of the module sealed so it went only outside the tender where it was installed. I would presume that might be called an "infinate baffle length". When I powered it up the first time, I couldn't believe the nice bass out of the steam engine.
By contrast, the sound out of the regular Athearn and even BLI engines is terrible. So terrible to my ears that I prefer to turn it off.
I mention these things because I'm convinced both the sound module and the speaker/baffle system are beyond sounding good due to their inherent design. It defies good acoustic design. TCS has come the closest to solving the problem, IMO. When I powered that engine up for the first time I inadvertantly said Wow! The next thing that went through my mind was, now I know where they got the name for the product. I just blurted it out.
Since it wasn't BLI Paragon 3, I wasn't able try it with Rolling Thunder, but I suspect it might have been closer to being satisfactory. That would not, however, solved what I believe is a range problem for all but much smaller layouts.
I don;t think BLI intend the Rolling Thunder to pick up from the entire layout room, it's more designed to have the bass come on as the loco gets close to the receiver. It's not going to have the range to link to a loco anywhere in a reasonably large layout room, unless perhaps you locate it amsck in the center of the room. The ability to hand off and work more like a mesh network would be a big improvement for using it on a larger layout.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
rrinker I don;t think BLI intend the Rolling Thunder to pick up from the entire layout room, it's more designed to have the bass come on as the loco gets close to the receiver. It's not going to have the range to link to a loco anywhere in a reasonably large layout room, unless perhaps you locate it amsck in the center of the room. The ability to hand off and work more like a mesh network would be a big improvement for using it on a larger layout. --Randy
Right; the Rolling Thunder manual suggests about 15 foot range, maximum, less under non-ideal conditions. But it also suggests potential ways to deal with larger layouts:
1. Buy more receivers and subwoofers (great for them, bad for the wallet). (Page 13 in the manual).
2. Add an additional receiver and run both receivers through the same subwoofer (page 17). Not as expensive, but will it generate sound localization problems if you get too far from the single subwoofer, especially at the higher end of the subwoofer frequency range (200-250Hz)?
3. Increase locomotive transmitter power using CV 213 (page 11, includes table of settings; 8 steps from lowest to highest transmitter power; I haven't checked to see what the default setting is).
This is all from the manual (online); I don't have a RT to actually try any of this.
I did #3 when I was testing mine. It helped some.
Thought I would resurrect this post. I just purchased a BLI Receiver to go with an SD9 I purchased. I am very disappointed with the range , tried all the CV tweaks they recommend and could not get it to work consistently. It acts like the receiver has a directional antenna in it as orientation effects pick up and drop off range. Does any have any experience gettin it to work well?
I can't speak to the range issue, but I just sucessfully connected the BLI receiver to my BIC subwoofer which wasn't as simple as it sounds. The BLI subwoofer is a 4ohm system and most home audio systems are 8ohm. Not a big deal, but something to note. When I hooked the receiver straight to my subwoofer it was way too loud and sounded terrible. Apparently the only way to adjust the volume is either on each engine's decoder or on the subwoofer. Neither solution was what I wanted, but understanding the BLI receiver signal is a line signal I found a nice product from Schiit Audio called the Sys which is basically a passive A/B box with a potentiometer knob. This allows me to switch between the stereo and trains and to adjust the signal from the BLI receiver so it now sounds much better. As noted earlier in this thread, it's not fantastic, but since both the receiver (a BLI refurb) and Sys box cost me a lot less than the whole system and let's me use by existing subwoofer, it's pretty good. The layout I'm building right now isn't very large, but I am thinking of putting the receiver near the center and just using longer RCA cables as needed.
SpringStreet My question: BLI's "official" subwoofer allows the low pass frequency to be set anywhere from 50 to 250Hz. The instruction manual recommends 200Hz. My alternative subwoofer would top out the low pass frequency at about 150Hz. Would I likely miss much, if anything, without letting higher frequencies through to the subwoofer (as BLI recommends)? I assume BLI opts for a higher frequency to capture some of the higher bass/lower middle sounds that on-board speakers also don't handle well, though perhaps at the cost of introducing more detectable localization of the sound source. Anyway, I'm wondering if anyone has tried this, what the results might be, and what impact different low pass frequency cut-offs might have. Thanks very much.
My question: BLI's "official" subwoofer allows the low pass frequency to be set anywhere from 50 to 250Hz. The instruction manual recommends 200Hz. My alternative subwoofer would top out the low pass frequency at about 150Hz. Would I likely miss much, if anything, without letting higher frequencies through to the subwoofer (as BLI recommends)? I assume BLI opts for a higher frequency to capture some of the higher bass/lower middle sounds that on-board speakers also don't handle well, though perhaps at the cost of introducing more detectable localization of the sound source. Anyway, I'm wondering if anyone has tried this, what the results might be, and what impact different low pass frequency cut-offs might have. Thanks very much.
The audible difference between 150Hz and 200Hz is insignificant in my opinion. I would just run it.
Remember, low pass filters do not completely cut off the high frequencies sharply. There is a smooth gradual roll-off. Look up the "frequency response" for your subwoofer and you will see that it's perfectly capable of producing sounds well above 150Hz.
If you listened to the subs side-by-side with headphones on you might notice the difference, but unless your train layout is in a sound recording studio or concert hall, most of those frequencies will get jumbled and disrupted anyway.