B460 and Velodyne sms1 combo

[opimax]

Over thanksgiving I picked up a b460 sub, relaced the 2245 and all done, right? Nope, a friend at work gave me an article written by Lorr Kramer and Greg timbers in Audio magazine on 8/83 called New lows in home-built subwoofers.

In the article it describes how to build you own b460 cabinet,8 cubic feet, an even larger 12 ft and how you can put a 2235 in the 8 ft . It also speaks of cross overs and of course mentions the BX63.

I assumed that all i needed was to hook up and go using the Xover built into my Sony 9000 receiver (7 x 200). it turns out the B460 is designed to get a 6db bump at 26hz. I am sure many already knew this but I didn't.

I think at this point It would be quickest and easiest form set up to get a Velodyne SMS-1 unit which among other feature can be set that way. At some point I would like to own a bx63 but the Velodyne is easier to obtain.

Has anybody else used this combo ?

Has anybody else used soemthing other than these 2 choices?

I am slightly concerned about draw on the amp once the boost is set in place. it is an Adcom gfa-555 2000w per channel, either 400 or 600 (can't find specs right now) bridged as how I use it. normally I would be quite comfy w/this power level but in today's music/movies I am not sure. in a loud movoe when bombs go off or the 1812 overture I don't want to fry anything w/a peak and that peak has an additional 6db

Thanks

Mark
PS is this the "proper" location for this thread? please move as appropriate

[Zilch]

The subject article is available in the LH libraray:

http://www.lansingheritage.org/html/.../1983-subs.htm

Worth mentioning is that DIY B380 is in there near the end, as well, though the port is different from the actual product.

BX63A is an easy DIY build. I consider B380 and B460 usable without one, but they need infrasonic protection if used at high SPL.

I easily modified 5235 for the 26 Hz Q=2 "bump" in 8,118 and 13,182 here:

http://audioheritage.org/vbulletin/s...ead.php?t=9901

Soime plate amps (e.g., Parts Express) come with built-in bass management EQ which can be set to provide the requisite filter....

[matsj]

Buy a Dbx Driverack and you can use it in the hole freqvency, not only in sub area.
I don´t think Sms-1 is bad ,but there is more than sub bass.

regards mats

[Mr. Widget]

I think at this point It would be quickest and easiest form set up to get a Velodyne SMS-1 unit which among other feature can be set that way. At some point I would like to own a bx63 but the Velodyne is easier to obtain.

I'd go with the Velodyne... it will allow you so much greater control over your sub... it is several generations away from the old BX63... it allows you to really maximize the woofer/room integration.


Widget

[opimax]

1st thanks for the replys. I have done a little research and think I will go w/the original plan. Normal every day use wll be the Velodyne but for extended 2 channel I will try the 63a once I can find one. I am enjoying collecting the ti line so I want the 63 for that reason alone, maybe like it once I hear it

This sub replaced a Velodyne SPL1200r and probably a second 1200r which I was going to purchase. I was surprised how well the 12 inch did compred to the 18 JBL. the 1200r has a good portion of the SMS built into it hoping tht is 1 reason why it sounds so good. If I can apply those same features to this sub even better . I think i need that 6db boost, at least so far w/just ear measurements. I might be a semi bass head I am begining to realize It is a home theater style and when I do watch movies don't need no stinkin Butt Shakers,lol. They aren't musical and music is first in my system.

The sms has an adjustable subsonic filter so that should take care of Zilch's observation, thanks for mentioning. any other quick and dirty adjustments, mods or other hints? I already have 2 adcom gfa-555 so getting a plate amp shouldn't be needed.

I have heard of DBX years ago, did they do something like electronic timing and imaging reverb ish stuff ? kind of like Hughes SRS and BBE ?

Lastly I happen to have a 2nd (origianlly in the box when purchased) 2245. back of my mind maybe a 2nd albeit home made b460? have the amp, have the speaker. Need a piece of foam, couple chunks of wood and voila 2nd 18 incher. The SMS can control multiple subs . Doubt it but it is a nice motivatioal thought to me, a goal

Mark

ps I will be looking at those threads later you linked Zilch, I will see what easy is to me on building the 63a . that would be "fun" project if I am able to do it

Mark

[Mr. Widget]

Normal every day use wll be the Velodyne but for extended 2 channel I will try the 63a once I can find one.

For critical "high fidelity" listening I wouldn't put either the Velodyne or the BX63 in the high pass signal path.


Widget

[opimax]

Widget,

Sincerly appreciate the input but I find I am lacking bass with out a sub. in another thread I explained that a little. I don't find the 250 a bassy speaker. could be the input(bass management in the receiver), most likely the room, maybe some stiff surrounds...

I have heard many times KISS , keep it simple including the signal path but even crossed as low as 50 or 40 it makes a large difference with out the sub (to me)

I have played w/the bass management on 2 different receivers w/the same results.

I think when I put the 250 back together I could switch positions w/the 120 and see if the results change

Mark

[Mr. Widget]

No, I wasn't suggesting to that you disconnect the sub for high fidelity... simply that you not run the high pass section of your signal through the crossover... anyway, it would appear your instincts were correct. Giskard just informed me that the BX63 uses a passive circuit for the high pass section so it would likely be fine used "as is" in a high fidelity system.


Widget

[Don Mascali]

I have used B380 clones that I built in 1984 using info from that Audio article. With enough power they are impressive and a single B460 probably is capable of higher output.

I have found through many placements, that with boundry reinforcement the bump filter really isn't needed. If you live in the size room most of us real people live in room gain will do the job quite well. Using a typical H/T receiver you can use the sub output to drive that Adcom and most have an equalizer to trim things up a bit.

I live in Haymarket and would love to discuss this and JBL in general with you. I will Send a PM with my number to use if you wish.

Good listening,

Don M

[opimax]

I will call you today as soon as I get a chance, damn job gets in the way of quality music ,lol

Mark

[soundboy]

I have had for many years two seperate systems with 2245H/BX63A's....and I wouldn't do anything else. One has 600 watts driving it, the other "only" 200 watts.....I am a long time live sound/musician/speaker nut....and I never even clip the 200 watt amp....it shakes my whole house with tight, deep, clean bass. The BX63A's are set at 80 and 90 hz, and the power supplies, high pass/low pass have all been modified with black gate and claritycaps...incredible improvement top and bottom...I can crank Level 42, and Mark Kings bass rattles the picture frames in my bathroom at the other end of the house. My amps are modified Adcoms, and they do just fine. I shouldn't be going on about it, because I would love another BX63, and I may be bidding against you for the next one!...just my two cents....there isn't a 12" on the planet that can move the air the 2245H can, with as low distortion....and ported correctly, I will always choose vented over a low Q (or ANY Q) sealed box....too dry, unrealistic to my ears, and I don't like boomy colored bass, I just like real kick and bass sounds at reasonable levels.....and, oh yeah, they sound great for dvd's as well...scary how low and powerful they are....

[mrbluster]

I agree with the limitations concerning the transparency of the BX63s' high pass. Was wondering If you could provide more details on what you did to improve yours.

[Zilch]

http://manuals.harman.com/JBL/HOM/Te...BX63A%20ts.pdf

[soundboy]

As I mentioned in my first post, I replaced the output coupling caps with claritycaps...origonally they have a polyprope with a small polystyrene bypass....not bad, but not uncolored....I am not sure if the Mundorf silver oils wouldnt be even better, though my experience with the beautiful sounding claritycaps has been excellent. Just slightly warmer than a straight bypass, and little loss of fine detail...they sound great Upgrading the low filter was a huge improvement, especially changing out the electrolytic blocking caps with 5uf or so polyprope. I used some old 5uf 450v siderealkaps I had from the parts bin...earlier version of the new auricaps (one of the same designers, anyway)....the high pass is only as colored as the caps you use...and you have to use a cap, right? A lot of guys use crossovers with ICs, caps, rf filters, low filters, etc...so this is a decent option, I think.

[opimax]

I have installed the SMS inbetween the Adcom and b460. WhenI auto eq the setup the only changes made to the curve is a 1.5 db boost at 50hz. When I did this at my brother's place using a Mirage sub the curve was all over the place w/ a 6db boost (max) at 20 to -11.5 at 40 and raised again up to 200. major diference between the 2 setups. His sub was 125 on ebay while I paid close to 1500 for amp and sub. Still I am very impressed at how little the eq was modded for my set up .


I have a question on the connection of the SMS. step 4 under step bystep installation talks about connecting the SMS EQ output to inputs on the amp. I don't follow the "need" for this part. I guess it suppose to go on the tape monitor and have some input to the all the time or does it go to a standard unused input and used only when setting up the SMS ?

Mark