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Gary Hunt
05-01-2004, 11:02 AM
Hi Everyone,

I'm new to this forum, am in Michigan and just moved a JBL Paragon system from my mothers house to mine.

Through the years it has mainly just sat in her house and not used. I hooked it up at my house and was disappointed in the very narrow frequency response out of the system. There's no real base or clean crisp highs. Only getting mid-range.

I pulled off the back panel speaker cover and listened closely to the 15" woofers and heard a very low and slight sound. Way to soft to hear or mix well with the mid's. Tweeters must have the same problem.

Maybe this is just the way a JBL Paragon is supposed to reproduce sound.

Is there anyone of you JBL Paragon experts and lover's of this very fine speaker that can give me any advise?

I did try to adjust the two setting knobs on the cross-overs, but it made very little difference in the sound. Is this suppose to be a dramatic change when adjusting these?

Thanks in advance for any help you may be able to offer me!

Gary
[email protected]

4313B
05-01-2004, 11:33 AM
Hello,

Grand Rapids is just a hop, a skip and a jump from me...

Gary Hunt
05-01-2004, 11:45 AM
Where are you located?

Rafael
05-02-2004, 01:50 AM
Gary,

adjusting the LX 5 knob makes indeed only a little difference but is clearly audible and useful to tune the midrange/tweeter output for different locations. Turning the L-pads on the N 7000´s should make a great difference on the 075´s and they should be adjusted in the "clicked" position. A new L-Pad can be the solution if you can´t hear a change in the output of the 075´s and when the 075´s are still o.k. Check the caps in all dividing networks. The woofer´s cone should move easily when touching gentle with your fingers. In most cases the foam surroundings are stiff and the woofers need reconing. The frequency range of the paragon is not flat, don´t expect very low frequencies and silky highs. I´ve heard many paragons and the results varied from dissapointing to fascinating. It mostly depends on the rooms and proper equalisation, but you can always hear a very coherent and "live-like" sound.

Regards,

Rafael

Regis
05-03-2004, 10:48 AM
Interesting nobody has asked Gary what kind of system he hooked it up to, how it was set up and what kind of material was he listening to. If he hooked up to one of those modern "600wpc" surround-sound systems that are so prevalent now, it's guaranteed to give disappointing performance. Secondly how is this system set up? Are the tone controls and the equalizer set up flat or at mid-point? This is so that you can get an objective "ear-point". Finally, material. IMHO, this is so critical. Just how a CD is mastered and how much headroom was on it DB wise. Some musical reproductions have all the headroom of a thin penny and sound about the same along with a crappy fuzz that many recording studios like to mix in to make it sound "loud". Other musical material had a very dynamic spread on it and it's super clean with tight solid bass and good seperation. Boy, does it make a difference. Gary, check all of the above, playing a wide variety of music. A good reference point in my opinion is something like Pink Floyd's Dark Side of the Moon, either Vinyl or a well mastered CD (limited gold edition). Most rock CD's just sound like junk, even in my L-150/L-110 combination, while cleanly mastered CD's like Praful's "One Day Deep" have incredible power and sonic clarity. Check the obvious!

Oldmics
05-03-2004, 01:41 PM
Hello Gary
Welcome to the Forum.Congradulations on your Paragon acquisition.Nice to keeep such items in the family.

From your description about the sound quality there may be some technical issues needed to be inspected.Since these things are so cumbersome to move I would like to make a few suggestions addressing the usual problems with the Paragon.

First is the lack of low frequency.This is probably due to the outer edges of the speaker cone stiffing up over the years(as Rafael has mentioned).This makes the cone hard to move and restricts the low end frequency response.Now there are a coupla different ways to repair this.The speaker(s) has to be removed from the enclosure.Once the speaker is out,inspect the outer edge of the cone.If it is an original LE15A speaker the outer ring will be white in color.Inspect this for any cracks in the white area.If no cracks are found-I would suggest to salvage the original assembly.To reactivate the white outer edge (Lans-a-loy surround) try using a coating of brake fluid on the outer ring.

Yep-brake fluid!

I know it sounds nuts,but do a search on the forum and read about the revitalising effects of brake fluid when used on Lans-a-loy surrounds.A search should also produce the application procedure using brake fluid.

If the surrounds are cracked,then repairs are needed by a qualified repair shop.Either a refoaming procedure or a reconing repair.Again ,I would try to salvage as much of the original parts as possible.This helps to maintain the value of the Paragon.The closer that it is to original,the more valuable it will be at resale time. I would refoam before reconing.

The hi freq issues are a bit more complex.You might want to pull all of the componets and take them to a qualified repair center for analysis.

It appears that a leading member of our forum (Giskard) is close to you.Perhaps you could contact him and he would be willing to inspect the hi freq devices and the crossovers.

I wish you luck with you repairs.As an owner myself of two Paragons,the investment in time and money for the repairs required on your unit will be positive for your listening pleasure.

Let us know how you make out,or send me a private message if futher assistance is required.

Oldmics

Gary Hunt
05-03-2004, 04:22 PM
I appreciate all of the advise, public and private. I plan on doing it right, when it comes to repair and will stick with keeping the speakers original.

I will keep this forum posted on what I find out and do to get them (woofers) working again.

Thanks Again!

Gary

Gary Hunt
05-03-2004, 04:39 PM
Regis,

You also make great points and I have tried several different recordings (CD and vinyl). I'm now convinced that the only problem I have is with low freqencies out of the woofers.

I'm using a United Audio Dual turntable w/Sure V15VxMR, McIntosh V4300 Tuner/PreAmp (100 watts stereo), McIntosh MCD7008 CD Changer and Monster Cable.

I did start out flat and adjusted from there. The highs sound nice and clean, but the changed on equalization did next to nothing for base/lows.

I plan to remove the woofers and inspect them carefully.

Thanks for your suggestions!!

Gary

Regis
05-03-2004, 04:41 PM
Nice stuff! You definitely have the premium sound equipment to drive that speaker to audio heaven once it's repaired! Just wanted to make sure and I'm glad you tested it out.

Rafael
05-04-2004, 04:05 AM
Gary:

Turning the knobs on the lx 5´s changes nothing in the woofer´s signal path, it only makes 3 different attenuating positions on the midrange and since they are wired with the N 7000´s it does the same for the 075´s. I think refoaming or reconing the LE 15´s solves the bass problem. When the surroundings are stiff, the speaker can´t go low. I had the same problems when I got my “C 44” 12 years ago- a time when really nobody could help you, even the guys at h/k knew almost nothing about this speaker. Thanks to the forum nearly every question (I´m still waiting for the energizer board numbers...) can be answed. I´m glad to see your paragon found a good place.

Regards,

Rafael

herki the cat
09-30-2009, 08:43 AM
Excellent advice from everyone responding to help restoration of this JBL classic treasure. Some items may need attention--more on that later.

Frst off, the low frequency responce of Paragon presents a wonderful important mid bass spectrum approx 100Hz to some 600Hz containing the speach fundamental frequencies and the important "Warm Heart" of the Music Bass spectrum, There is excellent response bellow 100 Hz and it is some what subtile because it is "Not !", the common Junk "Fat Boomy" HI- Fi Bass Sound.

The Paragon Superb Alnico JBL 375 Mid Range Driver, [brother of the massive Alnico JBL 2440 professional verson of JBL 375] has no competition in this industry when it comes to the superb aluminum diaphraphms with half roll suspension extremely clean in the mass break spectrum up to some 10 kHz. just like the well known Field Coil four inch WECO 594-A Driver from the BELL LABS Fletcher Classic Horn system. You can confirm this with JBL Forum Grand Father Guru Stephen Schell.

The Tweeter high frequency Divers are superb. Save these at all costs.

With respect to the restoration___

Item #1) Due to oxidation of silver contact surfaces, the level switches & volume level attenuators to the various compression drivers may need cleaning of contacts or replacement since old components some times are intermitant or not functional at all. Take care when turning up amplifier gain to prevent dangerous intermitent bursts of speaker driver power drive in these situations.

Item #2) The "United Audio" Turn table does have some rumble that may interfer with low bass speaker performance. This is a respectable TT, but you may ned a good rumble filter if if you EQ up the bass tone controll.

Item #3) all of the electronics driving this Speaker System must be of high Quality compatablity. it sounds like you have some very knowledable
hands - on people working with you already
-----------------------------------------------------------
My best regards Herki The Cat

quote=Rafael;20291]Gary:

Turning the knobs on the lx 5´s changes nothing in the woofer´s signal path, it only makes 3 different attenuating positions on the midrange and since they are wired with the N 7000´s it does the same for the 075´s. I think refoaming or reconing the LE 15´s solves the bass problem. When the surroundings are stiff, the speaker can´t go low. I had the same problems when I got my “C 44” 12 years ago- a time when really nobody could help you, even the guys at h/k knew almost nothing about this speaker. Thanks to the forum nearly every question (I´m still waiting for the energizer board numbers...) can be answed. I´m glad to see your paragon found a good place.

Regards,

Rafael[/quote]

Gary Hunt
10-17-2009, 05:38 PM
Hi Herki the Cat,

Your reply and ideas, as to how to get the sound/bass to present itself are wonderful.

I especially like the idea that the switch controller may need cleaning. I will certainly check it out. I think it should be an easy process to open it up for a little looking over.

Thanks again Herki!

Gary

sonofagun
10-18-2009, 06:14 AM
Wow - apparently this has been a long time project for you. I'm only 100 miles north of you, have been in the speaker business many years, and have heard Paragons before if you still need help. Have you thought of posting pictures?