Audible Nectar Posted March 19, 2002 Share Posted March 19, 2002 If anyone's having difficulty with a JBL Pro order this week, their web ordering/email is down. I found out when my order for 2 of the 4638 bass cabinets did not go through on my CC, so I called JBL. They think that the orders are cached in the server, they will have a web update about this on thier website soon. If you have placed a recent order, and have had a similar problem, do not attempt to place it again (you may end up getting both filled). JBL told me to watch the website for updates. BTW, they did say that they had 290+ of the 4638 cabinets - (so I should get the order filled). ------------------ First we Rock, then we Roll! Quote Link to comment Share on other sites More sharing options...
Vavoline Posted March 21, 2002 Share Posted March 21, 2002 OK guys, I feel like I'm in over my head here, but this deal sounds too good to pass up. As far as hook-up goes, how many terminals are on the 4638s. Do you just run a pair of wires to them from the amp? I would have to aquire an amp to drive these, but do I need a mono amp or a two channel? The pre-amp I have has 2 outs. One set of stereo outs, which I use with my 2 channel amp and a set of outs for use with a pair of mono amps. What are these parts express amps many of you are using. Mono? Stereo? Please excuse my ignorance, but I want to know what I will be getting myself into before I get a 100 LB, 4 FT tall sub in my house and then have no idea how to hook it up. I was at the tent site earlier and had credit card in hand, but thought I better ask a few questions first. From what I've read on this BB, everyone seems pretty satisfied so far. How would they compliment my Cornwalls? Thank you in advance for any help you can offer, Paul Quote Link to comment Share on other sites More sharing options...
Audible Nectar Posted March 21, 2002 Author Share Posted March 21, 2002 You should be aware that the JBL 4638's are not true "subwoofers", but woofers - that is to say that the JBL's are not rated for as low output as the SVS would be. However, the initial comments indicate that the JBL in an enclosed room gives output to 25hz or so, at very high SPL - and very tight and clean, BTW. I noticed that you were looking at SVS subs in another thread. I was looking at the SVS 20-39 CS+ pair with Sampson 1000 amp for $1599 plus shipping (delivered for 1850 or so). These are tuned to 20 hz - quite low - and have gotten raves from all who own them. I decided the JBL way was more bang for the buck, without compromising quality - but maybe a few hz on the low end. The SVS is a great way to go, if you have the dollars. They will keep up with the Cornwalls just fine, and would be a great choice for sub bass in your system. With the JBL, you need one channel of amplification per bin (each bin contains 2 woofers). This is a mammoth deal - I talked to one of the JBL people the other day, and he told me that these cabinets are $1100 each at list. I ordered two! Will it keep up with the Cornwalls?? Oh yes! These woofers are 100 db efficient with 600 watts power handling capacity - enough to get 120db output, or more. The Parts Express amp is mono. You can run the preamp outs (line level) to the sub amp, then line level back to the 2 channel amp. (this way your main amp for the cornwalls only sees what the sub doesn't). There are speaker leads on the parts express sub amp that connect to the JBL - but you will need solderless connectors and additional speaker wire, since the speaker leads on the PE are short, and meant to be wired manually on the sub amp end. The JBL cabinet has one positive and negative connection. ------------------ First we Rock, then we Roll! This message has been edited by dndphishin on 03-21-2002 at 10:31 AM Quote Link to comment Share on other sites More sharing options...
Vavoline Posted March 21, 2002 Share Posted March 21, 2002 dndphishin...Thankfor the info. That doesn't sound so complicated. This is the only part I have doubts about: "The Parts Express amp is mono. You can run the preamp outs (line level) to the sub amp, then line level back to the 2 channel amp. (this way your main amp for the cornwalls only sees what the sub doesn't). " Do you have to do it this way, or is just recommended? I'm no techno-genius by any stretch of the imagination.I'm not sure I understand the " line level back to the 2 channel amp" bit. Also, will an amp be all I need to get to start thumpin or will I need an EQ? I am really starting to get excited about this deal! Where would be a good place to aquire an amp for these monster woofs.Any web sites you could recommend would be helpful. Or..JMON..I see we are neighbors ( Practically ). Where in DAllas would you suggest. The only local HiFi establishment I have ever dealt with is Hillcrest HiFi. I'm pretty sure they are going to be a tad on the expensive side for what I want. Any suggestions. Thanks Again! This message has been edited by Vavoline on 03-21-2002 at 07:20 PM Quote Link to comment Share on other sites More sharing options...
Audible Nectar Posted March 21, 2002 Author Share Posted March 21, 2002 Vavoline - Let's re-evaluate... Do you have a 2 channel or a home theatre preamp? It sounds like you have a 2 channel. Scenario #1 You should be able to simply run the RCA's from the mono outs on your preamp (assuming that the stereo and mono outs will put out signal when they are all connected), to the RCA in on the Parts Express amp. Run both mono outs, to take up both the left and right input on the sub amp. Then connect the speaker leads from the PE amp to the JBL, and the Denon leads to the Cornwalls (that part would stay the same as it is now). I am assuming that the preamp does not have a crossover. If it does, scenario #1 works fine - you can use the preamp's crossover, and bypass the one in the PE sub amp by flipping a switch. If it does not have a crossover, you may consider another option. Scenario #1 works great in a 2 channel system if you want your Cornwalls to play as low as they can go, and you are looking for the JBL's to pick up where the Cornwalls roll off on the low end (Cornwalls are good to 40 or so hz, Jbl's would play below that). However, the JBL's are some serious woofage, so you may consider letting the JBL's handle some of that low bass, taking some load off of your Denon amp and Cornwalls. So, I present scenario #2: If you want the JBL's to handle more of the bass range, you will want to run RCA's out of the "stereo outs" on the preamp to the PE sub amp, then run RCA leads back to the Denon inputs (which plays the Cornwalls). This way, the Denon/Cornwalls only see what the sub does not (the Denon/Cornwalls are then relieved of playing the low bass, gaining a performance edge). The Parts Express amp is passing the signal to the Denon/Cornwalls without the lowest bass that the JBL's will provide. What method is best? Can't really say for sure, but for a 2 channel system, I'm inclined to go with scenario #2. You can try both, to see what yields the best results. With scenario #2 you can adjust the crossover point to see what balance gives the best performance. If you have a home theater preamp, the possibilities become more numerous, but manageable. I hope this helps - I'll check in again later. ------------------ First we Rock, then we Roll! This message has been edited by dndphishin on 03-21-2002 at 07:35 PM Quote Link to comment Share on other sites More sharing options...
Audible Nectar Posted March 21, 2002 Author Share Posted March 21, 2002 Just got the call from JBL - the 4638's are on the way I called them back today and they had me re-place the order. If you placed an order on the website within the last week, check your CC to see if the charge went through - if not, call JBL. I placed the order again through the website, and the customer service rep gave me a confirmation call, due to my trouble with the first order. Happy Happy, Joy Joy!! ------------------ First we Rock, then we Roll! Quote Link to comment Share on other sites More sharing options...
Vavoline Posted March 21, 2002 Share Posted March 21, 2002 dndphishin, Thanks for taking the time to spell it out for me. Your time and effort are MUCH appreciated! In answer to you question about my pre-amp: No, it does not have a crossover. Yes, it is 2 channel, NOT home theater. This is actually starting to sound like something I could handle thanks to your very informative yet easy to understand assistance. I will be online all night tonight ( shiftworker ), and will wait for any other responses you or anyone else may have. If it still sounds as clear cut as it does right now, I will order around midnight. YEAH!!! What about an EQ..do I need one or can I skate by without? Any web-site suggestions for tracking down an amp? Thanks again!! Paul Quote Link to comment Share on other sites More sharing options...
Audible Nectar Posted March 21, 2002 Author Share Posted March 21, 2002 Sub EQ's - you could skate by without, but I'm doing my homework on them now. I'm looking at two. Behringer Feedback Destroyer (1124 model priced at $139-$179) - here's a primer that explains the unit better than I can. link The BFD is actually an anti feedback device, but has flexible abilities as a parametric EQ. Rane PE17 ($399) - sold through SVS and elsewhere, also a parametric EQ. I'm still researching these, but both appear to be good options to control those JBL beasts by flattening the room response. ------------------ First we Rock, then we Roll! This message has been edited by dndphishin on 03-21-2002 at 09:13 PM Quote Link to comment Share on other sites More sharing options...
Vavoline Posted March 22, 2002 Share Posted March 22, 2002 dndphishin..YAAAHOOOOO...I just clicked the submit button on the JBL order form...and it felt gooood!!! Can't wait to confirm my order, then order my PE Amp. I want to thank you for all the helpful info. I'll let you know how it sounds when I get it hooked up..oh, wait..you already know how it sounds! I will be off-line for the next couple of weeks, but will post when I get back.LOL Paul Quote Link to comment Share on other sites More sharing options...
J M O N Posted March 22, 2002 Share Posted March 22, 2002 Vavoline: If you are looking for used equipment, try the following websites: www.audioshopper.com www.audiogon.com www.audioreview.com and of course, Ebay For local sources, Audio Insight and Audio Concepts will probably be even more expensive than Hillcrest, but they do carry used gear, and sometimes you can get good deals. John Fort Audio/Video is also a good place, but I'm not sure if they carry used gear. Since you have a two-channel system, it sounds like you are going to need both an amplifier as well as a crossover. The subwoofer plate amps that dndphishin is talking about should meet your needs and may very well be the most cost effective solution. Have you received your 4638's yet? Quote Link to comment Share on other sites More sharing options...
Vavoline Posted March 22, 2002 Share Posted March 22, 2002 JMON Just ordered them 10 minutes ago. About that crossover..is that something I will need in addition to the parts express amp? Quote Link to comment Share on other sites More sharing options...
Vavoline Posted March 22, 2002 Share Posted March 22, 2002 dndphishin, maybe I didn't resd your reply closley enough: "I am assuming that the preamp does not have a crossover. If it does, scenario #1 works fine - you can use the preamp's crossover, and bypass the one in the PE sub amp by flipping a switch. If it does not have a crossover, you may consider another option." My pre amp does not have a crossover. Does this mean I will need to get one or will the one on the PE Plate amp work. I hope I didn,t misunderstand!! Thanks Quote Link to comment Share on other sites More sharing options...
Audible Nectar Posted March 22, 2002 Author Share Posted March 22, 2002 Vavoline - the crossover is built into the Parts Express amp, so problem solved. ------------------ First we Rock, then we Roll! Quote Link to comment Share on other sites More sharing options...
Vavoline Posted March 22, 2002 Share Posted March 22, 2002 dndphishin, Thanks for the timely response. I was getting nervous. Man, I wish I had discovered this BB years ago. Ready to Thump, Paul Quote Link to comment Share on other sites More sharing options...
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