Power amp for Jbl L65 Jubal

[TWR]

Hi friends, for sure I'll do some errors (English is not my language), so I'll try to be schematic.

Instruments: Jbl l65 Jubal, Sansui au 9500, Naim cd5si. No vinyl, no streaming.

Music: I'm going to divide it into three groups.

a: Pere Ubu, Captain Beefheart, Faust, This Heat, Dna, Public Image Limited, Jesus Lizard, Cop Shoot Cop, Unsane, Big Black, Sonic Youth, Royal Trux, Chrome, The Fall, Pussy Galore; Thin White Rope and so on.

b: Nick Cave, Gun Club, Mark Lanegan, Wovenhand, Velvet Underground, Giant Sand and so on.

c: Leonard Cohen, Bob Dylan , Neil Young, Townes Van Zandt and so on.

No jazz, no classical music.

Listening volume: medium or low. No party, no crashed walls.

Problem: I like my instruments, but in particular, with the first group of musicians, I think my Jubals should give me more impact. They say these speakers need to be feeded, so, with 600/700 dollars, I would like to obtain a 200w power amp. I have got this list: HK Citation 22, Adcom Gfa 555, Carver 1.0t., Sae l2400. I like the sound of my Sansui (totally restored and recapped one year ago), so I would prefer a warm or neutral power amp, not too analytical. The pre amp will come later.

Question: anybody here who listens this kind of music with Jubal (or L100, 4311, L166, L112 and so on) and a power amp belonging to the list I have compiled? Are these power amps good with vintage Jbl? Other suggestions?

Thank you!

Carlo

 

[SaturationPt]

I'll paste my response to your LH thread here for reference:

Which L65 version do you have? There are three, if there is an A or B behind the serial number you have an L65A or L65B, all different woofers. There is no capacitor in the signal path to the woofer, so that should not be a problem.

Be sure that you have the correct woofers, and that they are in good condition with the proper (foam) surround attached to the back of the cone, and in good condition. Improperly "refoamed" woofers can degrade your bass. Also, if they have been used hard it is possible that the AlNiCo magnet isn't as strong as it once was (L65 & L65A).

Are they on the floor on their original risers or up on stands? The original floor-standing configuration is how the were designed to (floor couple) develop their bass. If you put them on stands you might need to EQ some more of whatever frequency you're missing.

Is the Sansui in good condition? Failing coupling caps can diminish bass, a weak power supply can degrade transients / reserve power.

A healthy 75wpc amplifier should give you good music from those speakers at your listening levels, provided all is in good condition and you're not expecting subwoofer bass. You can very inexpensively add a quality subwoofer to your system, it might be all that you need and will save you an amplifier change, if the main speakers are "high-passed" at 60Hz or above and hand over the amplification to the subwoofer the 75WPC from your Sansui will be available for the rest of the spectrum, should be more than enough.

I can't recall all of the amplifiers I've had hooked to my L65As, but felt that they sounded as good as any of the 12" 3-way JBLs of that era regarding dynamics and bass. Most likely they were played on my MC240 (50WPC - valve amp) among others, and didn't lack in dynamics.

The most important thing IMO when looking at making a change, especially one that costs money, is measure measure measure. If you can get into that room with a calibrated mic and something like REW software you will be able to tell what you're really hearing, and where any deficiencies might be. It could be something as simple as a bass-wave cancellation / reflection (aka: "suck-out") at a critical frequency which makes them sound lethargic. More power will mean more reflection, and you're "pissing into the wind" on this fix. If you can't measure, try different speaker placement, move them a foot further into the room / from the back wall, try a different wall, be sure it's the amp before you start to change components.

 

[daveg3588]

Welcome to AK, Carlo. I have the L166 and L200t3, drive them with a MC 2200 ( 200wpc ). I went from a B&K 2140, 140 a side to the Mac, there was a large difference, more impact, openness. I have used a Citation 19 and Adcom 535, The Citation 22 would be very good, the GFA555 is also a neutral amp. The Jubals are the early model of the L65, they would benefit from being raised off the floor, the bass will tighten, and bring the mids closer the ear level, I raised the L166s about 12 inches.

Listen to SaturationPt, he is one of our gruels!

 

[markd51]

Not sure who's told you such information, or drawn such conclusions, but no L-65 Speaker, no matter the version needs 200 watts of Amplifier.

I'm confused where you say such power then state medium or low listening levels.
In fact, I'll go as far to say, pump 200 watts though those speakers and you'll be repairing blown drivers, and fried crossover networks.

Think quality watts, not gobs of watts. You may be expecting these speakers do do things they weren't designed to do. And that is provide earth shattering bass. The bass they can provide is fine for what they are.
But if you're looking for really deep-low registers, get a powered subwoofer. It will take a lot of strain off both the speakers, and your main amp.

75-100 wpc is plenty to power them. I can understand having headroom, sure, you could hook 1000w amps to them, but get crazy with the volume dial, you will damage them. Trust that you wouldn't be the first to do such.

 

[markd51]

On the other hand, a too small amp-receiver, or any others, and you want to test how much it will give you, crank it to 9, cause clipping, and you can probably fry the speakers with as little as 10-15 watts.

 

[Mr Boochie]

Carlo, if I were in your situation --- I'd look for a good, powered subwoofer (or two).

 

[SaturationPt]

 

[SaturationPt]

Sorry, I meant to post this:

"Amp Power" is specified as 200W for the A and B, so not sure what is needed.

Also to correct, my L65As did say Jubal on the boxes and the instruction booklet. I believe that JBL called all three versions "Jubal"

 

[Mr Boochie]

FWIW, I'm running 150-watt Anthem amps for my L300 and DIY subs. Both are fine, in terms of tight bass, transients, smooth tonal response. I really don't think you need a lot more, as long as the amp has good damping and transient slew rate. A stable power supply.

 

[TWR]

First of all, thanks to everybody. Really. Then, I'm going to add some information about my system.

I own the first model of L65 series, the “real” Jubal, if I can say so. The woofers are correct and the foam is in good condition. At first I used them on the floor, then on a couple of miserable plastic Ikea stools, finally on 15 inches mdf stands, the latter with the best results. My Sansui was completely restored and recapped one year ago.

In the original brochure they write “for reproduction of the full dynamic range of contemporary recordings at high volume, a quality amplifier delivering up to 150 watts RMS per channel will provide optimum performance”. As Jeff wrote, the maximum recommended amp power for L65A and L65B models is 200 watts. I don't know if this difference of 50 watts depends on the different model of woofer used in the Jubal series or on something else.

When I wrote that with some kind of music I would like to have more impact, I didn't mean that I feel a lack of bass frequencies, but that I would like to hear this music more “unveiled” or more direct. As Dave, lots of L65 (or other vintage models) owners say that to obtain this result, even at a moderate listening volume, you need a very powerful amp. I used my Jubals also with a Krell Kav 300i (150w) and a Sansui au d11 (130w). I didn't like the character of these amplifiers, especially of the Kav, but probably (dazed and confused memory) I felt the music more present and real.

Thank you again!

Carlo

 

[Mr Boochie]

Yeah, to echo the other posters, advertised wattage is only a percentage of what is important in any amp. Headroom, transients (slew rate), power reserve, and a clean adequate power supply are all equally important. JBL woofers like good damping factor, too --- to give that tight, punchy, clean bass which JBL woofers are noted.

Your crossover may need some new caps. It should be tested. That may clean up the midrange and help with the resolution.

Good luck!

 

[TWR]

Questi sono i miei crossover. non posso giudicare...

 

[billyz]

Read the Brochure again. It says "Up to 150w" Not 150w minimum. Quality over quantity of watts. 25-50 watts of quality will sound much better than 150w of hard edgy nails on chalk board power. It also says "75 Watts ", efficiency is a little harder to decipher, but I would say around 90db + at 1w 1meter . I am running a set of JBL 4411's with a 40watt receiver and I really cannot imagine needing more power. The 4411 has similar specs to the Jubal . And they really perform best with a high quality tube amp. I used to run a set with a Harmon Kardon Citation II and they sounded fantastic. I tried high power transistor amps , Hafler DH500, Transnova, Carver, Adcom and the Citation was head and shoulders better .

 

[TWR]

Yes, up to 150w. I'm not sure (it's only a supposition) that a tube amp would be the best for my music, in special for post-hardcore, industrial and post-punk. Even if, as you can see, I didn't choose a contemporary amp, but an old, musical Sansui, not so close to the tubes after the recap, but even not so far.

 

[markd51]

First of all, thanks to everybody. Really. Then, I'm going to add some information about my system.

I own the first model of L65 series, the “real” Jubal, if I can say so. The woofers are correct and the foam is in good condition. At first I used them on the floor, then on a couple of miserable plastic Ikea stools, finally on 15 inches mdf stands, the latter with the best results. My Sansui was completely restored and recapped one year ago.

In the original brochure they write “for reproduction of the full dynamic range of contemporary recordings at high volume, a quality amplifier delivering up to 150 watts RMS per channel will provide optimum performance”. As Jeff wrote, the maximum recommended amp power for L65A and L65B models is 200 watts. I don't know if this difference of 50 watts depends on the different model of woofer used in the Jubal series or on something else.

When I wrote that with some kind of music I would like to have more impact, I didn't mean that I feel a lack of bass frequencies, but that I would like to hear this music more “unveiled” or more direct. As Dave, lots of L65 (or other vintage models) owners say that to obtain this result, even at a moderate listening volume, you need a very powerful amp. I used my Jubals also with a Krell Kav 300i (150w) and a Sansui au d11 (130w). I didn't like the character of these amplifiers, especially of the Kav, but probably (dazed and confused memory) I felt the music more present and real.

Thank you again!

Carlo

I cannot ever recall the Jubal Owner's Manual stating anything about a 150 watt amp? What it does say, is power handling is 75 watts continuous program. And 75 watts is a lot of power, wake the dead levels if you were to throw that much power into them. And those are high enough wattage levels that damage can possibly occur.

A real 25-30 watts is quite a lot of sound with these speakers. I powered my four Jubals with two McIntosh MC-2105 Amps for many years, in fact over 3 decades. The sound was very good.

Very smooth, clean, very good bass response. Nothing seemed to lack.

Subwoofers aren't a speaker to use if you're looking for better articulation, clarity, definition. As mentioned, a sub can provide more bass loading in a room, making the speakers seem "larger", that's where a lot of wattage gets used by an Amplifier. The Mid and Tweeter perhaps need no more than 20 watts max to strut their stuff.

If I recall, the two L-Pads on the Jubal are only 10 watt units. High frequencies are funny like that, take a blues guitarist in a small venue with a Fender Twin Reverb at 85 watts, and he cranks that amp to 5-6, trust me, everybody would be running out of the place, or would go deaf "ala Jimi Hendrix", which I once heard he was one guy you didn't want to see in an indoor setting.

Sansui made lots of good stuff over the years. As good and as refined as say McIntosh? I'd say that usually-commonly no, the Mac stuff was often still better sounding,more refined, and of course you paid for it too!

Again, like I say about a sub, they can help, but also can alter and not properly compliment the main speakers in a system. Yeah impressive maybe if you threw on a Michael Jackson Thriller CD, but remember too, is that actually how the music supposed to sound? Is then, a specific person's personal likes properly and sonically correct? Or some head banging metal head's definition of such who doesn't really understand what correct fidelity should be?

And like I say, a sub can take a bit of strain from both the main speakers and amp.

I'm still a little confused about what it is you're dissatisfied with, and ultimately trying to accomplish?
Realize that the Jubal, while a very fine speaker, is also not in the realm of say the JBL M2 Reference Monitor. Nor did/do they cost $16,000 a pair if I correctly recall the M2's price tag.

Sure, there's speakers out there, that will give you more slam, let's say some old huge pair of Cerwin Vegas, or the larger JBL Models, but the Jubal can make some nice music if upstream components are of very good quality.

Your Jubals may not be the weak link. You cannot expect the best in digital CD sound of say a $9,000 Krell CD Player with a $129 JVC job bought from Circuit City 25 years ago.

I've heard good improvements with upgrades to source components, both digital, and analog.

We might assume your Sansui or other gear you have to be in tip top shape, and plays like new. And then again, maybe it doesn't? As an old audio saying goes, "garbage in-garbage out".

 

[TWR]

 

[TWR]

This is what I found. As I told before, Mark, I think that we have always to consider the kind of music we listen when we choose our system. So a very defined amp is not my cup of tea. Just for the reason that I have lots of very bad quality recordings.

 

[markd51]

This is what I found. As I told before, Mark, I think that we have always to consider the kind of music we listen when we choose our system. So a very defined amp is not my cup of tea. Just for the reason that I have lots of very bad quality recordings.

"Whataya Want, Good Grammar, or Good Taste"? Looks like a 150 "warm watts" is your desire.

OK, I see that now what you say about the 150 watts. Trust I don't have quite that good of a photographic memory all these years later but without doubt had/have 4 of those manual booklets that came with those speakers because I bought 4 of them brand new around 1975-1976.

And I still have those 4 JBL Jubals, their factory boxes, and manuals. While they are in superb cosmetic condition and outwardly intact with nary a mark on any of them, their Crossovers, L-Pads and Speaker Binding Posts are modified-upgraded.

I had the crossovers custom made to factory specs, with much higher grade, and higher wattage rated components throughout, 10W L-Pads which got scratchy-intermittent were replaced with 100W Models, and Edison Price Solid Copper 5-Way Binding Posts.

OK, enough about me, and some of my back-history, and back to you, and what you're discussing here.

There's nothing ever wrong with great detail-definition, clarity, as long as you're not hearing fingernails on a chalk board. One nice feature I would say with your Sansui Integrated, and just about all vintage gear like yours, or PreAmps, Receivers back in the day, is that they all had tone controls. Much of the very same equipment today has zero, nothing. Unless you look to a company like McIntosh, which on a lot of their gear still provide such adjustments by the end user.

I've read of way too many people today who lack such and then go onto expensive and seemingly never ending journeys of Cable Rolling, Speaker Rolling etc etc, because they are never pleased with their sound. Because of a preamp, that lacks any such adjustments.

And again about wattage, 150 watts as JBL said, and like I say, it can be 1000 watts. That such extra power on tap is reserve and provides headroom for what they/you refer to as transients. Your Sansui should be able to provide enough.

I could hook a meager Sansui 210 Receiver to my Jubals, and they would sound nice. And I could also hook up my 600 watt Bryston Monoblock Amps to them, no problem. And in any instance, large or small, just don't get stupid with the Volume Control.

Again, and what you're wishing for is not easily determined, at least not by myself. I think what one thing you are touching upon is "warmth". You want warm sounding Solid State Gear, or Tube Gear perhaps?
Many vintage pieces of gear seem to be voiced this way, the older McIntosh, and Marantz gear come to mind. There's nothing at all wrong with vintage gear. There's countless folks who want nothing but.

As for the Jubals, keep in mind you have L-Pad controls. I always left mine flat for mids-highs. To me, their voicing always sounded best left neutral. I never have discounted what the minds at JBL produced. They knew a hell of a lot more, than I ever will.

Speaker positioning, good stands, and perhaps properly integrating a decent sub can offer benefits. Many people here will tell you about Subs, if you can detect where it is, because you got that thing cranked to the moon, that is not the proper use of a sub in a "Audio System". I'm not talking Home Theater systems.

I have a Sunfire True Sub MK-IV, I bought it new, and have teamed it with my Jubals, Mac Amps, the whole smear. Sure, that little 50lb 11" cube could shake the house apart, have anything not nailed-screwed down buzzing-rattling, just stupid crazy. Great if you're watching "Demolition Man", but not at all when listening to Classical, or really to tell the truth, any music where you expect truthful audio reproduction.

Good ole 'Fabio", ever hear of him? Yeah, the "I can't believe it's not Butter" Guy, plastered on countless fiction love novel books with his long flowing blonde hair, a huge Krell and Martin Logan Fan. Said he once had subwoofers in his glass house cranking out **** so viciously, everybody present began to get sick from the below 20hz signals, and like James Dean once said, "You're tearing me Apart!!!!" LOL

I love, and listen to all "music". And note I say Music, not (c)Rap retard ****. That ain't music! That's all mostly **** created by devil drug riddled minds, "bust a cap"and all that infantile ghetto bullshit.

You want to hear real music, basically listen to anything else!

You seem at an impasse, looking to perhaps spend some more money, but you don't know where? The "weak links", that's one guide.

 

[TWR]

Thank you, Mark. You're right: I'm at an impasse. In any case I won't sell my Sansui. I'm just curious to verify if I can obtain something different with a more powerful amp. That's it. At the moment I'm not thinking of a tube amp, as Billy suggested, but who knows? I could really love this solution.
Finally, I'm the guy who uses tone controls. You must use tone controls if you listen some kind of music.
Ah, about rap. It's not my music, but I'm not so critical. Lots of interesting things there. Then Bob Dylan loves rap and that's should be enough for giving rap a chance.

 

[SaturationPt]

I was an early adopter of the 2.1 channel stereo, bought a new M&K Volkswoofer & Sattelite system in ‘79.

A poorly integrated subwoofer is not going to give the presentation that a properly integrated one will. However, a properly integrated subwoofer? You won’t be able to tell it’s there.

I don’t recall the response limits of the Jubals, but pretty sure it starts to lose steam around 40Hz. If you want lower you will need a sub, no amount of power will make up for the lack of cabinet volume.

If it’s imaging and presentation of the midrange, you need different speakers, I felt that my Jubals were decent on bass (standing on the floor, so the floor helped the bass response) but were weak in the midrange. Power and punch weren’t a problem IMO.

I really think you’re looking at the wrong thing in wanting more power, but more power is never a bad thing, so give it a shot. ADCOM is usually good inexpensive power, not a bad suggestion from whomever posted that above.