Sigh....I'm stuck

Yea, I know, I am lucky to be able to do this. The price was right at less than $100 to rebuild the pair even if they are 3' tall. Here is a pic of the right corner. The left is just as tight and the rack is 4' wide. Ft. Knox bank employed to hold sewing measuring tape in place.
 
Now that's very interesting to say the least. Yeah, if I could build something a bit smaller but on the same principal it must might fly. Hmmmmmm
 
A third choice, if you want to try one it Rel Acoustics subwoofers - very musical with no boom. Very expensive, though.

I can certainly vouch for that! I have a REL Storm III sub paired up with some Klipsch RF-7s! One of the most musical and accurate subs I've ever listened to! It is a downward firing 10inch driver in a ported cabinet. I've never heard any kind of port noise. The bass is just so friggan tight and clean, it is almost unbelievable. I sometimes wonder if it even on. It just seemed like such a natural extension of my Klipsch speakers. But, yes, it was expensive. I paid a good $2K for mine.

Also, I've heard Martin-Logan Descent subs and they seem to have a very tight and clean bass that seemed very musical.
 
you have heard this tired song before from me I guess...

Hey WW, tasted SET and want to try the real hard drugs now huh? :D

Well, I guess you already know what my opinion is here as we discussed this at length when I visited and it looks like I’m pretty much in agreement with Mikebake. Good, big woofers done right (no small feat!) will get you part the way there but I really think when you hear the dynamics and presentation of a good high efficiency, probably at least partially horn loaded system with SET’s you’ll want to go all the way, but I hear yah, 1 step at a time.

On your MTM’s – hey, you love them so why dick with em? I’m not familiar with the details of this design but I suspect a lot of development went into getting that crossover just right and it probably goes way beyond simply picking a cross point and slope which is about all you can easily do with in an active crossover. Add to that that unless you spend big money on a tube unit, you are putting solid scrape op amps between your SET and those speakers you love – personally, no thanks. There may be some real advantages to rolling off low bass to the MTM’s though (I remember how those little cones danced!) so a crossover down low to big woofers might be a good thing. Actually, I’d want to try a crossover scheme like the Dahlquist design ProAc suggested – active SS high order (18db) lowpass rolloff on the big woofers and shallower (6db) passive line-level highpass crossovers to your MTM’s – just a cap in the signal path. I’m not a subwoofer fan 95% of the time but the best bi-amp integration I ever heard (aside from Edgar’s Titan system) was Dahlquist DQ-10’s with this type of crossover and Dahlquist woofers (not “subwoofers”). This would also give you the ability to keep your system’s strength’s in tact (tube pre, SET amp to your MTM’s) while using SS where it really shines – low bass.

On woofers and cabinets - I’d rule out real horns (I mean real ones) for deep bass unless you are willing to put something the size of a large refrigerator in your room. I know people will say there are small ones that work but there is no cheating physics – to get horn loaded bass down into the 30’s you need a huge mouth (even in a corner) and a long horn path length – read BIG. Maybe I’ll find I’m wrong about this someday but I sure haven’t heard any horns smaller than a large appliance that pulls this off yet. 2 bass horns that I have heard and liked which you could build are the Edgar seismic and the Labhorn but I think when you comprehend the size of these things you will run away very fast.

My preference for woofers (if I can’t have a real horn) are large format (15”) “pro” market parts with powerful motors, light paper pulp cones, cloth surrounds, highish Fs, low Qt, high efficiency – yes, Altec, JBL, TAD type stuff. These won’t go real deep and usually have to go in large vented cabinets but you end up with a high efficiency woofer (not subwoofer) that has fast, dynamic bass that can sound like the real thing. Nice starting point too if you decide to try horns for the rest of the range. The spec sheets say you can have lower bass with smaller cones flopping around in little boxes but I gave up on listening to spec sheets - the large pro type stuff just sounds more like music to me.

All just my opinion of coarse (hey, you asked :) ).
 
Last edited:
Hey Bill, you know I always like your .02 cents. Yeah, I enjoy my MTMs Joe D'Appolito is no dummy and this MTM with the Raven ribbons is a well thought out unit. But you know this hobby as well as I do and...and...AND I WANT MORE!!! LOL What I think I am going to do to give me a "fix" until Denver in October is use this nice lil crossover that I just now snagged on the Bay http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=14977&item=3089112138&rd=1
Build me some stereo deep bass cabinets and push them with a Marantz 240 amp. Tubes on top, SS on the bottom. Should be fun for now. Once I get back from Denver and the show maybe I'll have other dreams and aspirations LOL Maybe? HA HA yeah right maybe my ass.... <snicker>
 
What you want seems similar in theory to gonefishins rig perhaps he might be able to point the way.

I totally understand what WW is saying about subs and music, I use the bottoms of my CV's as subs in HT and they work great but when I play music using them thru the AVR as subs it just sounds wrong compared to the way they sound thru my pre amp. Not bad and to most folks they would probably prefer the sound using them as subs, deeper boomier bass, but to me it sounds wrong, not as responsive, not as dynamic, not as balanced.
 
Wildwest I think you should look at these tweeters before getting some of the Raven's which I hear is a good tweeter but these have already had alot of acclaim from the DIY community. Two speakers equipped with them won 1st and 2nd place at the DIY speaker event. It's called the Aurum Cantus G2 Ribbon Tweeter and here's a link for them:

http://www.aurumcantus.com/english/g2g3/g2/g2.htm
 
Woofers. What a pain.

I wrestled with integration issues for years. When I was using low efficiency cone/box speakers, cone/box subs worked fine and still do. Now that my main speakers are high efficiency Lowthers, the cone'box subs that worked fine below LS3/5As sound all wrong. Like they're half a beat behind the music.
I tried the horn sections of my La Scalas to shore up the bottom end of the Lowthers and that kinda worked, so I knew I was on the right track. I eventually lucked into a pair of Klipschorns that had been cut down into bass bins and jumped on them. The original passive crossover was gone and a custon line level 24db xovr was included. With Klipsch K33 15" woofers inside, these integrate beautifully with the Lowthers. I roll them in starting at about 90 hz, which is where, contrary to what Lowther partisans will tell you, the Lowthers really drop off like a stone. The electronics are schizophrenic. I use a 45 SET amp for the Lowthers, with no xovr. For the subs I use the line level SS Xovr, a SS eq and a SS poweramp. Whatever works.
I will eventually clean up the crossover region in the Lowthers by tailoring the response of the SET amp to produce the rolloff that I want. I wrote a universal spreadsheet for designing high-pass factors into SET amps. You plug in cap values until the graph looks the way you want it to. I'll use this to get my crossover region right. The spreadsheet is free to anyone who wants it, just email me.
I have found that the larger the room the larger the radiating surface is needed to get smooth bass coverage. This room is 36' X 24' and needs 2 X Khorns to get the bass right. Smaller rooms have few problems with cone/box subs, but if I try one in here, the bass sounds best in the kitchen hallway and adjacent half bathroom. That's nice when you're getting a beer or offloading one, but useless at the main listening chair.
Bass is the most mysterious and frustrating aspect of music reproduction because it does not behave according to intuitive straight line rules. Attempts have been made to quantify and predict through computer simulation the behavior of a woofer in a room, but these are most relevant in idealized rooms without doorways, furniture, wives, etc.
We're left with an approach made up of hearsay, opinion, cut-fit experimentation and subjective evaluation.
My advice is to beg/borrow/steal as many bass options as you can and try them all. When it rocks, it rules. Sorry I can't be more objective, but there's no easy answer to this difficult issue. You've had some good advice from other posters in in this thread, and a number of options t opursue.
One final piece of advice is that the more experimentation you do the lower the ultimate price of the solution. It's a balance of dollars vs hours. You can go to the local audio salon tomorrow and lay down the long dollar for their best powered sub and get great performance. Three months from now if you've been diligently experimenting you'll probably be able to reproduce the same sound for a fraction of the price with a home made solution.
I don't envy you this, but you can have fun and learn a lot doing it.
Cheers
 
Dan dude...look at my avatar. See those MTMs? Now look in the middle between the woofer drivers. Whatcha see? Yup, they be Raven R1 tweeters. I already have them and have had them for a couple of years now. I am hooked on this pure transducer ribbon sound I tell ya. The Aurum is a newer introduction on the market and doesn't quite have the track record that the Ravens do. Although I too have heard good things about them.
 
I knew WW had Ravens. The problem with getting bass to go with those MTM is speed. The 2 best ways to do that is horns or isobaric. Check out a pic of Wards' HT and you can see 30 Hz horns under the ML pannels. When we (me) put on some Yes the bass had to be dialed all the way down to keep the horns in line and the MLs neded to be goosed a tad with a bit more treble.
The horns indeed kept up with the stats but tended to be overwhelming.
Possibly because my set up is different it is much easier to dial in the bass, but for the most part it is seamless, the music sounds great and the bass keeps up with the Heil AMTs which are quicker than Ravens.
I can see bass horns designed by Paul Klipsch keeping up with Lowthers, but not with Ravens.
 
Originally posted by Thatch_Ear
the Heil AMTs which are quicker than Ravens.


LOL now, now...I would say, NOT. While many of the more vintage crowd like the Heils, they really weren't built to well and the diaphrams are tougher to get. There's a fellow in the DIY forum you sent me that used to sell them. He will tell ya... :yes:

I'll put my Ravens up against your Heil's 8 days a week bubba...

:boxing: :D

By the way, shoot me a PM Thatch, I have some interesting news.
 
Back
Top Bottom