JBL L Series (1990s)

[BMWCCA]

I think most folks realize low frequencies are what takes the power, L7's can take ~500-600 watt bass hits without much trouble. One of the added benefits to bi-amping is that by having two amps (even if they are of modest power, say 120w each) running high and low frequencies, you don't have the same problem of a bass hit soaking up all your amp headroom and then having distortion/clipping in the high frequencies because if it.

Yes but since this is passive bi-amping—or two-amp bi-wiring as JBL calls it—you're not really separating the full frequency range as you would with an active crossover and true bi-amping. That's been the philosophical question asked here about passive two-amp bi-wiring that's never really been put to bed: Does the amp really have a lighter load just because the speakers can't produce the full range even though you're feeding full program material to both the high side and the low side of the L7's passive crossover? In fact, for this type of hookup, JBL recommends the same amp power rating for both the LF input as the MF-HF input.

It's just MHO, of course, but my impression from trying this with two Crown PS400 amps is that it really makes no difference other than that brought on by wishful thinking. It might help if the amps just weren't that powerful but I've not tried the bi-wiring with my PS200s. Now you can do real active bi-amping with the L7s but you'll need an activer crossover and you'll have to go inside the crossover to move a jumper to truly separate the crossover sections.

[Fred Sanford]

Yes but since this is passive bi-amping—or two-amp bi-wiring as JBL calls it—you're not really separating the full frequency range as you would with an active crossover and true bi-amping. That's been the philosophical question asked here about passive two-amp bi-wiring that's never really been put to bed: Does the amp really have a lighter load just because the speakers can't produce the full range even though you're feeding full program material to both the high side and the low side of the L7's passive crossover? In fact, for this type of hookup, JBL recommends the same amp power rating for both the LF input as the MF-HF input.

It's just MHO, of course, but my impression from trying this with two Crown PS400 amps is that it really makes no difference other than that brought on by wishful thinking. It might help if the amps just weren't that powerful but I've not tried the bi-wiring with my PS200s. Now you can do real active bi-amping with the L7s but you'll need an activer crossover and you'll have to go inside the crossover to move a jumper to truly separate the crossover sections.

Nothing conclusive here, but just as a point of reference:

I'm running 4333As bi-amped, currently in a sort of combo active/passive setup that may shed some light on this question. The signal from my DAC splits and hits an active x-over for the low-pass, then to a 60W amp, then to the 15" (passive does not stay in line in this configuration). The other side of the split signal heads straight to an identical 60W amp, then in to the top section of the passive crossover (which stays in line always) & on to the horns. In my head, the amp running the highs is seeing full-range signal at its input side, and amplifying full-range signal, therefore it's not running as efficiently as it should/could. Some here have said that the passive filters remaining in line reduce the load on the amp to some degree, I can't honestly say that I understand the theory behind that (that's a reflection on me, not on them). The interesting observation to me is that the high freq amps light the clip lights well before the low freq amps do - this tells me that I'm wasting amp power on the top end, and this semi-passive bi-amping doesn't really gain much for me.

Yes, I'm eventually going to upgrade my active crossover to address this, and add a second GFA 2535 to the mix, giving me ~200WPC lows and 60WPC highs, all properly filtered at the input signal side. My hesitation so far is that a simple/typical active crossover has only one freq & slope selection, and I'm not confident that with the high freq passive filters in line I can get satisfactory results without potentially fighting against those filters. Dual freq & slope crossover settings and properly calibrated analyzing tools would be the way to go.

je

[hjames]

I thought you had an Ashley active EQ available over there ...?
Or did I have too much fun in my college daze?

Nothing conclusive here, but just as a point of reference:

I'm running 4333As bi-amped, currently in a sort of combo active/passive setup ... and this semi-passive bi-amping doesn't really gain much for me.

Yes, I'm eventually going to upgrade my active crossover to address this, and add a second GFA 2535 to the mix, giving me ~200WPC lows and 60WPC highs, all properly filtered at the input signal side. My hesitation so far is that a simple/typical active crossover has only one freq & slope selection, and I'm not confident that with the high freq passive filters in line I can get satisfactory results without potentially fighting against those filters. Dual freq & slope crossover settings and properly calibrated analyzing tools would be the way to go.

je

[Fred Sanford]

I thought you had an Ashley active EQ available over there ...?
Or did I have too much fun in my college daze?

Ashly active, yep, doing only the low-pass to the woofers @ 800Hz. When I try to use it for both highs & lows, though, I can't seem to get it to:

1] not have some overlap with the passives still in place on the high side

*or*

2] cut off the low-pass too low, leaving an audible dip in the response around the crossover point

I'm thinking I need an active that has independant crossover points & slopes for highs and lows. One cheap temp fix might be Harrison Labs F-Mod high passes in line at 500Hz before the amp for the horns.

je

[JonJeffman]

Fred, your issues are kind of in line with the questions I've always had about active biamping - while there are theoretical benefits to it, am I really going to have the knowledge and measurement tools to properly set the crossover freq, slopes, and attenuation to balance out drivers of various efficiencies, better than the fine folks at JBL did originally? Are active filters pretty user friendly and are the x-over freq & slopes easy to find for most speakers?

I found this website very informative regarding the theoretical benefits of active biamping, and kind of says that passive biamping doesn't do all that much. Guess I'll have to try it out someday when I can afford to have several amps kicking around.

http://sound.westhost.com/bi-amp.htm

[JonJeffman]

Can I hijack this thread back to the L5 for a minute? I'm quickly realizing that the 'going rate' doesn't seem to apply up here in Canada, and since they're not easily shipped I'm stuck with what I can find, but how much of a deduct do you think missing grills are worth? And are the grills purely cosmetic? I know on Paradigm's website they say the grills are part of the diffraction/wave guide design and should be left on.

Also, the seller claims these are 6 years old - aren't these much older than this? Was there only the one version of L5, no L5b or anything like that?

Any opinions, as always, are greatly appreciated.
Thanks,

[evans224]

Can I hijack this thread back to the L5 for a minute? I'm quickly realizing that the 'going rate' doesn't seem to apply up here in Canada, and since they're not easily shipped I'm stuck with what I can find, but how much of a deduct do you think missing grills are worth? And are the grills purely cosmetic? I know on Paradigm's website they say the grills are part of the diffraction/wave guide design and should be left on.

Also, the seller claims these are 6 years old - aren't these much older than this? Was there only the one version of L5, no L5b or anything like that?

Any opinions, as always, are greatly appreciated.
Thanks,

The last time the L5 was made was 1996.
The missing grills should not affect the sound. However, asthetically they make a big difference. Parts are no longer made for these, and I have very rarely seen the grills come up on eBay. I would think they would be worth around $200-250

[BMWCCA]

The L5 is unique within this series in that it uses two grilles per speaker. Of course you don't need grilles on any JBL and there's some argument as to whether or not many sound better without them. But you asked about how that affects their value and I'd have to say drastically if you ever hope to resell them. If you only want to listen to them, don't mind the look without grilles, don't ever want to sell them or don't care about how much you'll get, and don't have kids that will kick or push-in the cones, you should be okay.

I don't know where you live in Canada since you don't say but I've purchased two sets of L5s in the Boston area for $200/pair or less and Boston is a lot closer to parts of Canada than it is to me. I don't know what price you're considering but since many speakers—including JBLs—that don't perform as well as the L5s seem to sell often in the $500 to $800 range, whatever you have to spend for a good pair of L5s can easily be rationalized in oh so many ways . . . if you really want to.

[Fred Sanford]

Fred, your issues are kind of in line with the questions I've always had about active biamping - while there are theoretical benefits to it, am I really going to have the knowledge and measurement tools to properly set the crossover freq, slopes, and attenuation to balance out drivers of various efficiencies, better than the fine folks at JBL did originally? Are active filters pretty user friendly and are the x-over freq & slopes easy to find for most speakers?

I found this website very informative regarding the theoretical benefits of active biamping, and kind of says that passive biamping doesn't do all that much. Guess I'll have to try it out someday when I can afford to have several amps kicking around.

http://sound.westhost.com/bi-amp.htm

When you're replacing a passive network with an active crossover before the power amps, I think the benefits can be immediate and the setup is relatively easy*...or at least experimentation is, and the results can be gauged by your own happiness. When you're combining an active with one or more passive filters that stay in line, it gets a bit more complex. I've actually approached this in a reverse order from most people, I've been using active crossovers almost exclusively in PA applications for many years. Unfortunately, most of my testing/analysing gear belonged to previous employers, so for now I'm without...though I may be acquiring or at least borrowing some soon.

je

[*] compression driver compensation would be one exception

[Slare]

I'm getting a little bored and was thinking about trying bi-amping with my L7's. I've thought about this before but my current room is small, and running subs hasn't made it all that important to me.

However my subs are on a dedicated amp that I have to turn on each time. Since it has a fan I tend to keep it off or it turns into a dust collector. Because of this and the capabilities of the L7's, I'm running in full range mode with no subs more and more often lately. Only firing up the subs up for a real sit-down movie session.

I prefer not to use the subs for music listening. Even with my subs balanced I just prefer pure 2 channel output on the L7's.

My receiver is a Denon AVR-987. A solid unit for a receiver. 110wpc with decent ratings (not 1kHz/10% THD type).

I have three different methods in mind using either one of two standalone amplifiers I have. I don't have room to use both amps.

1.) NHT B-20 subwoofer amplifier. This is an odd peice of equipment but offers 250x2rms at 8ohms with a built-in active high pass pre-out. It's meant to be used in a studio setup that has a seperate top end amplifier or powered monitors. So I could use it to drive the bottom of the L7's (low pass crossover is defeatable), and send the 110Hz (highest setting available) hp into the Denon, which would then power the top of the L7's. This would be the truest bi-amp setup as I'd have some active crossover keeping everything under 110Hz out of the top end receiver amplifiers. I think this would be best.

2.) Kenwood M2A Basic - a pretty solid ~250wpc amp rather good headroom and low impedance drive compatibility. Use this to run the L7 bottom, Denon runs the top, but there is no active crossover working.

3.) Kenwood M2A Basic - Just run it full range to the coupled L7's and skip the Denon amp alltogether.

Any thoughts? I've attached the B-20 amplifier manual if anyone is interested. They pop up on ebay from time to time and are a rather spectacular bargain for what you get, if you need such an item.

I have odd equipment as I'm a bargain hunter. The M2A basic was a craigslist find at <$50, the NHT unit was an ebay grab for ~$150 that I eventually intended to use as a DIY basement sub amplifier...

[JBLAddict]

Yes but since this is passive bi-amping—or two-amp bi-wiring as JBL calls it—you're not really separating the full frequency range as you would with an active crossover and true bi-amping. That's been the philosophical question asked here about passive two-amp bi-wiring that's never really been put to bed: Does the amp really have a lighter load just because the speakers can't produce the full range even though you're feeding full program material to both the high side and the low side of the L7's passive crossover? In fact, for this type of hookup, JBL recommends the same amp power rating for both the LF input as the MF-HF input.

It's just MHO, of course, but my impression from trying this with two Crown PS400 amps is that it really makes no difference other than that brought on by wishful thinking. It might help if the amps just weren't that powerful but I've not tried the bi-wiring with my PS200s. Now you can do real active bi-amping with the L7s but you'll need an activer crossover and you'll have to go inside the crossover to move a jumper to truly separate the crossover sections.

after touching on my experience upgrading my L7 source from a 75WPC HK-AVR, to a 230WPC Soundcraftsmen, to 2x230WPC Soundcraftsmen in the Consumer Amp section up until yesterday, I though it more appropriate to continue that discussion in the L series speaker thread where other L7 owners might find it. This last post from August turns out to be seamless lead in.

Having now had 3 days to test out the "two amp biwire" as it's called in the L7 Supplement, I can attest to what others have said in this thread about the improvement, per the Supplement recommendation:

"In fact, since the crossover point for the L7's HF/LF connections is 150Hz, using amplifiers of the same power for both woofer and midbass/midrange/treble connections is recommended"

Without overstating, I'm finding a very noticeable difference in MF/HF output and detail. Initially, I thought it overly bright, but then realized the seemingly recessed mid-range character of the L7 (which I was never happy with) just wasn't being fully being brought to life, and what I thought was an overemphasis on LF may just have been a power imbalance. Vocals, snare drum shots, and cymbals are much more pronounced and more back toward the forward character I was accustomed to for decades on my L100, the bottom end has dropped a few dB (noticeably and a good thing), all in what seems a much better balanced output across the freq. range. When hearing the Everest2 I was taken back by the presence of LF coming from 2-15" without being overwhelming (as I considered the L7 to be prior to the two amp bi-wire).

[Titanium Dome]

Great insight and thanks for posting it here.

There's a lot of improvement to be had from this relatively easy procedure.

[Regis]

....Without overstating, I'm finding a very noticeable difference in MF/HF output and detail. Initially, I thought it overly bright, but then realized the seemingly recessed mid-range character of the L7 (which I was never happy with) just wasn't being fully being brought to life, ......

Just got done listening to the L7's and I agree about this recessed Midrange characteristic. The 4315's and many of the other JBL's have a much more pronounced and forward midrange than the L7's demonstrate and I like the solution. Just have to double up on the amps, though I'm going to have to make them XLR capable. Oddly enough, the L5's don't have this problem.

[Regis]

Another 8 hour round trip yesterday to San Diego to pick up two pairs of the L series. Initially, it was just the L7's, but then a near mint pair of L5's came up too in the same area and I just had to have them too.

I first, must thank Sir Ti Dome for his concise documentation of his impressions of these way-underrated JBL speakers. They neither have the panache of the vintage 70's JBL's, nor the absolute newest technology of the Performance Series, Synthesis, Array, etc, etc. So their kind of stuck in the middle and that's a good thing bargain wise, as I picked up both pair for very cheap, even by recent L7 prices. The poor economy sure helps the buyer on just about anything these days.

Went home at lunch today to hear them, as I didn't get to demo them when I purchased them.

First, the L5's. My main system is being stored far away, so I had little choice for what was driving them today. An old, but OK sized Yamaha Home Theatre receiver, with the CD's played through a vintage RCA dvd player of el-cheapo quality. THe wiring is that tiddly tiny black wires you'd find on a shelf system. But something is better than nothing when you want to try them out.

As the CD started to play, I had to admit that I was somewhat surprised at how good the L5's sounded. The bass is really solid. No, it doesn't go to really low frequencies, but what's there can easily be felt in the gut and the chair and is tight and clean. The crossover and the speakers make for a seamless transition across all the drivers. There is a nice coherence and evenness across all of them. The sound is nicely detailed without being overly bright or forward. They are a really nice sounding pair of speakers and I could easily live with just these alone. You could almost live without a subwoofer supplement with these as they are that good. The 8" woofer does a surprising job of kicking out more-than-adequate bass.

Now the L7's. These are great speakers, but the recessed midrange is definitely there. I was thinking, maybe, no midbass hump as was popular on so many 70's JBLs, but I think as JBLAddict and Ti Dome note, something can be done about this. The sound was pretty good, nicely detailed and if you fix the midrange recess, they'd be a solid performer. The bass has some serious power to it. The lows go really low, with good dynamic range across the lower frequencies. No lack of power there, that's for sure. With an amp (or amps) with some huevos, a decent CD player and real wiring, I'd bet that the L7 would solidly kick some behind. They sounded as good with smooth jazz as they did with other material, like Techno or Industrial music. The placement wasn't optimal, but it wasnt' bad either.

I am glad to have both pair. I like them a lot and look forward to hooking them up to a real system soon.

[JBLAddict]

Regis, always a pleasure to have a new L-series owner join in this discussion.

Since the L7 in particular has so much that can be done WRT power, placement, wiring, there's much that can be discussed, compared, and experimented.

Right off the bat, yes, the L5 is pretty amazing all around. There's almost nothing you can say bad about it, just does everything about as perfectly as something of it's size and configuration could do. As I mentioned in other threads, the current LS80 which goes for 5K a pair and I had a chance to hear, is IMO embarrassed by the humble old Circuit City L5. Talk about a dead lifeless mid-range, listen to an LS80

The L7, is as BMW has accurately stated however, the true grown up in this family, bringing so much more muscle and a soundstage that is absolutely incredible. The narrow time aligned baffle provides this, while still maintaining the deep bass that comes from the elongated cabinet containing a 300mm woofer. It's not necessary to have them 3ft from the corners, but it allows the unique design to reach it's max potential.

Now onto that mid-range characteristic, no matter what you do, it will not have the same forward character of a studio or near field monitor, it's simply not designed that way. The recessed mid was something I noticed IMMEDIATELY when I auditioned them and "the owner" switched over to his XPL200 and PT800, compounded by my coming off 30yrs of almost nothing but L100A listening. Powering them properly (and adjusting my ears to accuracy) has helped. Also the designer Chris Hagen clarified that the speaker is near 4ohm impedence from 150-300Hz and 3-5kHz, so if underpowered these freq. ranges are starved. As I progressed from 75WPC, to 240WPC to 2x240WPC, the mid just got better and better--properly setup, it's accurate and uncolored, and a good blend with the rest of the system. On well recorded vocal material, they can blow you away.

Now ALL that being said, I still think the mid is the weakest part of this speaker and there are times that I simply miss the really forward, revealing mid of my L100. On certain material the voices were right there with me. Unfortunately, on too much material, that forward character is the speaker's worst enemy. While the L7 overall is amazing, they never achieve that "breathy" or "scratchy" vocal trait (which I personally like), rather aspire more toward "smooth", and if that's the design intent the really excel.

The last comment I'll make, is even though I have mine 3ft from the corners, I think my 13X16' living room is too small for them. The back of the room opens up to the kitchen and when I stand back there they are much more open and articulate, the L5 doesn't quite have this problem but at the same time doesn't have the LF impact or magical soundstage of the L7. However.....I ordered about $400 worth of absorption panels on Monday from the source TiD recommended, so we'll see what improvement that makes.:dont-know After buying a new AVR, two amps, and room treatments, I think my L7 upgrade road will come to a close, and the next step, if any, will be new speakers

Once you have a chance to hook them up to a bit more power (and do not keep the binding straps on, use home made jumper wires or two sets of wires if you have to), pls post your impressions, especially on that mid-range area.