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Need advice...driving some vintage JBL's

Welcome to my first post!

Flashback - after getting out of college in '86 and securing a job and apartment, it was time for a decent sound system. At that time the absolute best sounding speakers I had ever heard were the JBL L100T. A friend had an uncle working for JBL and I managed to get pair through him for $550 shipped to my door (they listed at like $600 each at the time). I promptly took the cash I saved and put it into a Hafler DH220 amp and DH100 preamp. I then got my hands on a DBX DX5 cd player and Onkyo TA2090 tape deck at an insurance salvage sale (water damaged boxes). When all was said and done I had less than $1500 in my system and life was pretty darn good. I was very pleased with this system. So pleased in fact that I bought a second pair of JBL's at an out of business sale for $400. It was a couple of days before I could get a truck and pick them up. As luck would have it, in between that time I was broken into and lost the Haflers and what little CD collection I had at the time. Needless to say, I moved shortly thereafter.

Flash forward to the present - believe it or not the JBL's remained in storage since the summer of '87. I've been living since with a Halfler SE120/100 amp/pre, the DBX cd player and a pair of Ohm H speakers. Well I've finally moved into my OWN home, I was ready to resurrect my JBL's and start looking at a new system. In anticipation of this I pulled out a pair of the JBL's this spring. The foams were rotted. I found a refoam kit on the net and refoamed them (all four). I tested them with the present Haflers and put them in back in the box (perhaps a little uninspired).

Last weekend I pulled the JBL's out and set them up in the living room for fitting purposes - they look absolutely wonderful with the current furniture scheme - OK, 5 stars for aesthetics. A friend brought over an Adcom system he's looking to sell ($700) and loaned it to me for a test drive. So here's what I have hooked up right now:

Adcom GFA-5500 amp
Adcom GFP-565 preamp
Adcom GCD-600 cd player

I've only got enough speaker cable (monster) to hook up one pair of JBL's so far. Nothing special on the interconnects - gold plated. This could very well be the reason however I am not too impressed. I did notice that things sounded a bit better after a couple of hours once things got warmed up. The following test discs were used as a good cross section of my listening tastes:

Dave Weckl - Synergy
Cassandra Wilson - New Moon Daughter
Steve Tibbets - Yr
Chris Whitley - Hotel Vast Horizon
Wes Montgomery - Far Wes
Jeff Beck - Guitar Shop

I guess anyone familiar with these artists would understand the range I intended to explore. Forgive me for not knowing all of the audio "porn" terms, but all I can say is that the highs were just too harsh and the bass was just too muddied and lacked punch. I know for a fact that these speakers are capable of sounding much better than this.

OK, so here is my situation: I'm rather attached to the JBL's and am not convinced that they are the worst sounding speakers going for me right now. The Adcom demo was convenient but I'm not impressed and do not believe that better interconnects are going to remedy that. I'm thinking if anything it's the amp but all I've known has been Hafler products.

As a novice audiophile, I'm looking for any recommendations one might have on getting me some decent sound out of these JBL's (all four of them). Perhaps someone has some experience getting decent sound out of a similar speaker.

I'm still working on my house so unfortunately I'm going to have to settle on a budget of $2000 for a decent amp, preamp and cd player. This is just an interim system so that I may be able to enjoy my music somewhat passionately in my new home. Maybe some suggestions on equipment that may later transition well into a home theater setup until I can afford to get serious with my primary audio again.

The listening room is 16' by 24' with 9' ceilings. The specs on my JBL's are as follows:

Recommended Power Amplifier Range: 200 watts
• Nominal Impedance: 8 ohms
• Woofer: 12" aquaplas
• Midrange Driver: 5" high polymer laminate
• Tweeter: 1" pure titanium dome
• Frequency Response: 35Hz - 32kHz
• Crossover Frequency(ies): 800Hz, 4.5kHz
• Sensitivity: 91dB (1 watt/1 meter)

Looking forward to some reasonable suggestions. Thanks.
slothman
flg2001's avatar
flg2001
543 posts
 
Some considerations:

1.- Take a look at speaker placement. You may need to pull those JBL out of the wall and place them on stands to make them sound great (I love L100 Centurys). a lot of content in this room wil help you out.

2.- Why 4 spkrs?

3.- I understood that the spkrs were NOB, you may need to let them play for 200-300 hrs after building any serious analysis arround their sound.

4.- Maybe you should need to "turn" drivers 90 degrees if they were stored floor standing, too many years may make the spider-air suspension weak at the bottom of the drivers. (leave this just after the rest of my considerations are applied)

5.- The best mate for Century(s) is IMO a McIntosh amp, it could be an integrated model.

Hope this helps

Fernando
rar1's avatar
rar1
1,784 posts
 
Sloth:

The JBL 100 were the consumer version of the JBL 4310 studio monitor. The JBL 100s were incredibly popular speakers and good performers, complete with alnico magnets. In using vintage speakers, the question that gets raised is whether they should be paired with a vintage amplifier or not. Here is a thread from the Vintage Asylum at Audio Asylum that talks about damping factor and how it affects vintage equipment. I am not sure if this affects your situation, but it may be worth looking into.

I say all this because you may wish to consider tracking down and refurbishing a 70's era high performing receiver like a Pioneer SX1010 or a Marantz 2325.

If vintage is not the way you wish to go, two good budget integrated amps to look at are the NAD C372 or the Rotel RA 1062($700 - $800 range, new). They will provide you with lots of good clean power and they sound good with a wide range of music. If the NAD & Rotel are too dry sounding for you and you want something more elegant sounding, take a look at the Creek 5350SE ($1400, new).

For your CD player, audition the Music Hall MMF CD25 ($540, new) or the Rotel RCD 1072 ($700, new).

Regards, Rich

jimburger
104 posts
 
I recently put together a retro system together for the bedroom. I found a pair of JBL L100A's and a Yamaha CR620 receiver on Ebay. The JBL L100 is a time machine for classic rock. Really takes yout back to the 70's. It ROCKS with the modestly powered(35watt into 8 ohms) Yamaha receiver(which I got for about $100)! I use either FM or CD(an old Philips CDR 880) as sources. A little off point perhaps but combining components from the same era will produce the sound that you remembered "way back when." I have not heard the L100T but if you feel that the titanium tweeter on the L100T is a little on the hot side, you might try a tube amplifier. With the JBL L100 speakers, you don't need high power as much as quality. JBL recommended in their 70's literature only a 10 watt amplifier as a minimum. A great match would be a pair of Quicksilver monos of almost any wattage. You can find them used for $1000 and under on Audiogon. Good tube preamps like Quicksilver's own or the Melos SHA-1 can be obtained for around $500. Leaving you $500 for a CD player. Take a look at av123.com. You will see a clone of the Music Hall CD player that retails for as high as $800 for about $300.
hiend2's avatar
hiend2
437 posts
 
That Adcom 5500 is a great performer, smooth ect. Ive owned these along with many Large format JBL's L300 ect.( And Larger ).
To me it sounds as if you are going to expect alot of the system. So something dramatic is in order.
May I suggest you do some research on the Rogue 120 mono block tube amplifers. These will blow your mind. Bit pricey pry around 1200+ but worth every penny. They will make a dramatic improvment. These are fast powerful and transparent.Dont waste your time with solid state. Although there are some excellent amps.Ive been around the block owned 12,000.00 krells, Thesholds, audio research, Adcoms, crowns ,Phase linears, aragon, VTL, Hurricanes, rogue, ect.
I will never forget the sound of the 120's by rogue audio.
They have the bass power and control you want, midrange smoothness of only tubes can provide and you will be able to reach into the recording and hear stuff like never before. They hold thier value well also.
slothman OP
311 posts
 
Thanks for all of the responses guys.

Some interesting proposals here. I would have though that a good beefy solid state amp would give those 12" woofers what they're asking for. I guess maybe it's time I take a good look at tubes. What about integrated tube amps? I guess at 91db, I probably would need to be looking at something in the 6 to 8 Watt range?

I going to play around with this Adcom setup more. From what I can tell the 565 preamp is respectable - maybe the CD player is the culprit. I talked to another buddy that's got a couple of DAC's and some decent cables I can borrow. In the meantime I'm going to explore the tube thing - plenty of information in here.

Thanks again guys.
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