chops

Gosh, only 8 replies?!?! ************************************************ What a shame. He'll definately be missed, but certainly not forgotten. []

This bass is in just about new shape. I just installed brand spankin' new RotoSound 665LD round-wound strings on it. The new strings have about 10 MINUTES MAX of very light play time in them. I also have the flat-wounds that came with it. I do not have pics with the new string, but can take some if asked. This is a great sounding bass that can do just about anything you want it to. I for one can not play the darn thing. I thought I'd be able to pick up where I left off with the old upright concert bass I played back in school, but it's a totally different ball game with an electric. Plus I thought I'd be interested in playing jazz, blues and fusion, but I'm not. I'd much rather stick with playing classical with a good ole' upright bass. The strap, chrome stand and RotoSound strings are brand new! The bass is in like new shape with very very little wear on the frets. There's no scratches, dings, dents, flaking paint or marks of any kind on it, front or rear. This bass really is in MINT condition! BTW, the flat-wound strings look to be fairly new as well and are in great shape. So anyway, if anyone is interested, I'll let this bass along with the stand, strap and original strings go for $300.00 plus FREE shipping in the CONUS! I will ship ONLY to the lower 48 states. I will ONLY accept PayPal. Please feel free to check out my Feedback on eBay (user name: chopsrr).

Hey Erik, long time! Jim told me about this amp you were working over. Very nice indeed! I take it that amp powers the HD650's fine with their 350 ohm impedance? My amp that Jim was referring to is the Little Dot Micro+. Nothing special at all. It's a little battery powered portable job which is only being used as a home based unit. It does amazingly well powering my K701's. Eventhough they are 67 ohms (IIRC) and fairly efficient, they still require a bit more current than this little amp can provide to really make them shine. It's still impessive though, and the battery lasted 255+ hours before finally dieing last night. At any rate, I'm in search for a nice tube amp for my cans. There are several of them floating around, mostly from China. They get pretty good reviews and all, but they all use tubes that are almost impossible to find, unless you live in China. Go figure... [8-)] Anyway, here's a few pics of my setup just for fun. Source: Sony DVP-NS755V IC: Signal Cable Analog Two w/ Eichmann Bullets Little Dot Micro+ AKG K701

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No, no, no... Sorry, I didn't mean for it to sound that way. No, I'm not running mine open baffle. I have 5 little curious kitties that roam around, and I wouldn't want them crawling into the Cornwalls, especially with that news paper-like padding that's in there. But don't think it hasn't crossed my mind a couple of times. [] I am planning on building a pair of bi-amped OB's though, using dual 15" drivers per channel and the Altec 511B on top. That's going to be interesting! http://forums.klipsch.com/forums/thread/822497.aspx

Happy Thanksgiving!

Hi Erik, Say, if those rear panels come off like they do on my Cornwalls, why not take the backs off and see what they sound like operating as Open Baffles? Sorry, I have no usefull input for your question but I'm also on my OB kick right now as well. It's all I've been thinking about for the last month or so. [8-|]

Dana and Mike, This DOES look like an interesting twist. Are those exponential baffles pretty much open in the rear? Kind of like an OB but folded in the middle? Neither one of you would happen to have any pictures of this kind of design, would you? Those drawings are a little difficult to go by. If these are something along the lines of what I'm thinking about, I might just try these out.

No necessarily. If both drivers are rated at say 98dB @ 1w/1m, then it still doesn't matter what impedence they are. IOW, 98dB @ 1w is 98dB @ 1w. BTW, I bet those chairs are cold as hell durring the winter season! []

My Dayton's are 8 ohms.

I just want to say "Thanks DrWho"! I was going to comment on that whole 8 ohm thing, but saw that you already did, and said it better than I was going to. [] Also, I would just like to say that I back up those Dayton DVC drivers very strongly. If properly implemented, they can deliver excellent results! http://chops.tzo.com/subproject.htm

No, unfortunately, not yet. For the past couple of weeks we've had a couple guys here at the house doing some remodeling. Right now, the rooms are a mess and can't move much around plus I don't want to get in their way. However, I am running a couple of ideas through my head with a different method of mounting the drivers to the baffle. It's called "magnet mounting" where the driver is held in place by the magnet on a bracket of some sorts, and then not screwed to, but held up against the baffle and sealed with some soft foam between the driver basket and baffle. http://www.decware.com/cgi-bin/yabb/YaBB.cgi?board=diy;action=display;num=1162819072;start=30#41 http://www.linkwitzlab.com/orion-rev1.htm I'm still trying to figure the whole thing out and see if it's really worth the effort or if it's just a bunch of BS. Have any of you guys heard anything about this method? Once we get the remodeling done, I'll hop back on this project with much gusto! []

I can't. I have a limited amount of space I'm working with. If I were to do wings on the baffles, I'd start getting in the way of the projection screen. Besides, you can start getting some of that "box" sound in the midrange if the wings are big enough to effect the backwave of the drivers. I meant wings extending back from the baffle - towards the back. It would take some experimentation but a combination of that and maybe alittle less EQ might be worthwile. Shouldn't be too tiresome to mount them temporarily and play around with things. They'd increase the effective baffle size without increasing the width. Yes, I realise that, but like I said before, the wings can "box in" the sound, especially in the midrange, and that's something I don't want.

I don't exactly know how to answer that, Mike. I've never tried them that way. I'm assuming they would make "some" bass if you're standing far enough away from the walls and holding it. Let's just say a low distortion driver is going to make absolutely no sound whatsoever...and there is effectively no difference between holding the driver in the air with your hand and putting the driver on a small open baffle. Huh?!?! What are you getting at?

I can't. I have a limited amount of space I'm working with. If I were to do wings on the baffles, I'd start getting in the way of the projection screen. Besides, you can start getting some of that "box" sound in the midrange if the wings are big enough to effect the backwave of the drivers.

I don't exactly know how to answer that, Mike. I've never tried them that way. I'm assuming they would make "some" bass if you're standing far enough away from the walls and holding it.

Hmmmmnnnnnn ....... it had never occurred to me that LInkwitz didn't know what he was doing ..[:^)] Nooo... I didn't say he didn't know what he was doing. The reason he chooses to use those drivers instead of the ones more desirable for OB is to make the entire loudspeaker look more pleasing and have a better WAF and to take up a lot less floor space. And in doing so, his designs need a lot more equalization and amplifier power to get decent output. And while there's 12+dB of boost in the bass region along with 5 times the needed power, the drivers need to be able to handle all of that with higher power handling and much higher Xmax. I'm just going "by the book" and sticking with the original design criteria because 1) I don't have to worry about any WAF, 2) I have the room to go with full-sized baffles to get decent output with a lot less EQ'ing and amp power, and 3) The drivers I use are less expensive and the overall design is much simpler. It's just a little harder for me to find decent drivers with a high enough Qts and low enough frequency response and Fs to get the same amount of bass while keeping costs down. And just an FYI, IF you stick by the "rules" of open baffles, everything the Peerless drivers are is exactly what NOT to look for in a driver more suited for OB's. Anywho... []

Mike, What kind of tube tester are you using? What all does it measure? garymd, What would cause a fuse to blow in the VRD other than a dead short? [*-)]

He's so busy listening to his new Xtreme that he hasn't even updated his sig yet! LOL []

Once I build them and see what they can do buy themselves, then I'll know where I have to boost. I honestly can't guess where I'll have to start. When I had those drivers in the H-frame subs, I used the EQ to ONLY cut from 63Hz up to 125Hz a little as they seemed to put out a little too much around that range. As far as from 60Hz down, they needed NO help at all, no EQ, no tone controls, no loudness, nothing. The Xmax is 6mm. I'm not going to be concerned with that. It will be plenty. Don't ask me why or how, but these drivers just simply do not move in OB's. However, there are other people that say the same of the drivers they use as well. I honestly think the ones that need a large Xmax are the ones that have no right being on OB's like the Peerless drivers that Mr Linkwitz likes using. They are small drivers (12"), have a low Qts in the 20's I believe, and are inefficient, somewhere around the 87- 89dB 1w/1m mark. Of course those drivers need a lot of Xmax because they need crap-loads of bass boost and power to get anything usable out of them below 100Hz.

Well since the "alternative designs" thread is getting a little jumbled (lol), I have decided to start a new thread. Just wanted to show everyone what my plans are. I may just get started on this little project within a week or so, maybe sooner. BTW, this is my first time ever using AutoCAD. The last CAD program I ever used was Generic CAD in DOS when I was about 13. I'm now 31! And yes, I realise that I forgot a couple of bolt heads on the bottom angle brace and center back brace. hehe I'm going to start this project off by using the Pyle Pro PPA15 drivers. Why? Well, because I have them and I know they performed superbly in my last dipole project. Also, I want to see how everything's going to sound first off before I go out shelling $$$ for new drivers. I will also be building these out of 0.75" MDF. Being that these baffles are going to be considerably smaller than the H-frames I built before, I am expecting to use some EQ'ing on the bottom end due to the earlier bass roll-off. The only thing that really concerns me with this is that I have never run those PPA15 drivers past 100Hz, so I have no idea how they're going to sound up around 600hz. I guess I'll find out soon enough though. At any rate, I'm looking forward to starting this project soon. I just need to find a room to stuff these Cornwalls into so I can get the OB's up and running in my music room. Anyway, let me know what you guys/gals think...

What kind of bass bins are you building, sealed, ported, horn?

Well I'de sure be interested walking through your house. But like you say, most people don't think or care about such things. "I don't know a damn thing about dipoles." Well how in the heck am I supposed to ask you for your advice if you don't know anything about them?!?! You better start reading up on them or something! LOL

Well like I've said before, I've had dipoles in this room, and even ran them up to 500Hz with amazingly good results. But because they were the H-frame design, I was getting a not-so desirable midrange out of them, as I would have expected anyway. I designed them as subwoofers, not fullrangers. However, with a very narrow baffle, this should be a non-issue, and the low end can be beefed up a little with my EQ. And sorry for hi-jacking the thread. Although, the title does say "alternative designs", and this surely is an alternative design to say the least. [] Shawn, thanks for your input!

They don't interact the same way as a typical "box" speaker does. They DON'T excite the room modes like a box speaker does. The side walls and floor only act as an extension of the baffles to lower the bass roll-off of the baffle, but they do NOT reinforce the bass already present in the music.