Aadams

Page 33 of the AR9 manual on bi-amping the AR9. Your PS Audio has plenty of power. http://www.classicspeakerpages.net/library/acoustic_research/ar-9_series_1978-1981/ar-9_series_manuals/ar-9_manual/ar-9_manual_pg33.html#previous-photo

What you are showing is original. Do the corresponding drivers in each cabinet appear identical?

The supplier is Wichelt Imports. A search on "Wichelt lambswool 18 count" will give a good list of retailers who may still have stock.

Properly restored AR5s are among the cream of the crop of all speakers, including new ones of today. Photos of drivers would be helpful so we all know that we are talking about the same things. For instance your pictures show glass fiber but you mention rock wool. Are your drivers original or service replacements? The resistor and woofer burned out from too much current, perhaps someone messing with signal wire with the amp turned on would be my guess. Adams

Glad to see you have them properly working. Almost. LST Manual Placement guidelines on page 2 first paragraph. http://www.classicspeakerpages.net/library/acoustic_research/original_models_1954-1974/original_models_manuals/ar-lst_manual/

You have plenty of room unless something else has priority.

The thread below will give you some idea of which 4x you have. Look at the Johneio post. The bottom line is it will be difficult to find a non AR replacement tweeter that will crossover at 1200hz or 1400hz and fit in the hole with zero crossover changes.

I have been reading your posts wondering what could be the problem because the only AR12 inch that is easier to set up than an AR9 is a 9lsi, which will be hard to come by for an even swap and parts are dearer. Have you read the AR9 manual section on room placement? Ideally you need 3ft on either side of the outside woofers but extreme asymmetrical arrangements can be accommodated. The only real constraint is placement against a short rear wall. And speaker separation can be as close as needed for a minimum listening distance of 3ft. Adams '

This is a 48bxi from the UK brochure in which the AR 78 is the lowest LSi model number.

KLH site says it should be shipping in April of this year. The appearance is more like a 3way large advent with a low woofer crossover. The specs look good.

The short answer is, you are probably correct about the pots. The bypass idea will not improve your speakers and will make them unbearable unless your ears are specially suited for the over-prominent mid-range sound of your modified speakers. Are you the original owner? Can you supply photos with grills off?

Assuming they are in good shape, all three of the woofers have near identical performance. There is no practical difference . The square magnet woofer is the latest version of the three. Same for the mids: Assuming they are working correctly you won't hear a practical difference, they are essentially the same. My recommendation would be to make sure every driver in your reassembled LSTs operates to your satisfaction before selling any spare parts. You should replace the fuses with new ones even if the old ones appear to work. If your LSTs have Sprague Compulytic caps throughout I would leave them. If they have a mix that includes ICC wax box caps I would replace the ICCs. Adams

The Walsh driver is an almost full range omni-directional driver still used by Ohm in their more expensive speakers. The Ohm L is a decent box speaker that does not have the Walsh driver.

If they don’t have a Walsh driver there is nothing special. If they do have a Walsh then how old? They are still in business and provide repair parts, some of which are expensive.

I knew there was a good image of a large value Sprague Compulytic on the site somewhere. This is from a 2006 thread about an early LST with a 5000mf that shows the capacitor is non-polar. A 2500 is on the right.

All the speakers required to make a 4 way LST that doesn’t need a rear wall.

Occasionally the question arises as to which AR speaker sounds the best. Of course, the answer is a subjective judgement but if one reads the product literature from the classic period, a stated goal of AR was to make their speakers sound the same. The graphs above, taken from the 1975 product brochure, show the AR5, 3a, LST and LST2 will all sound the same, above 500hz, to a listener positioned, in relation to the speakers, as depicted in Fig2 . Below 500hz, they will also sound the same except at lower frequencies where woofer size and room boundaries affect bass performance. Additionally, if the Allison guidelines for 2pi placement are followed, all these models can be made to sound indistinguishable to the limits of their performance capabilities. The graphs also apply to the ADD dome systems and even to the AR9 Vertical series, though the area of uniform power response of the Verticals was intentionally narrowed. Beginning with the AR3a and ending with the AR58S, all AR speakers that used dome mid-ranges can be made to sound the same because the drivers are fundamentally the same units, only modified in appearance and sturdiness. The Main Differences: The top-of- the-line speaker of each generation made it easier to achieve deep flat bass performance in a home listening room. The LSTs could be placed against a wall, rather than in it, as required by the 3a and 11. The AR10pi had circuitry to achieve 2Pi bass output without regard to boundaries. The AR9 and AR90 yielded near automatic, very deep, flat bass if placed asymmetrically against the narrow wall of a rectangular room. The 91 and 92 had their woofers positioned higher off the floor with additional circuitry to give pretty good results when placed on the floor near a rear wall. All these speakers can be made to sound the same or practically the same above 200hz, if their placement is identical with respect to the listener as suggested in Fig2. Technically, there is no best sounding AR speaker from the roughly 15-year span in question. There are only differences in the amount of futzing around with placement, level controls and electronics required to achieve the sound that pleases you.

Yes. I saw that yesterday and elected to remain quiet because the OP did not claim ownership of the speakers pictured. This thread now has enough off topic material to make it volatile.

Kent is correct. If you still want ready made wires it will be difficult to find for those models. If you are not willing to DIY by attaching spade or ring termination to the wires then your quickest path to ready made wires are these, below. Spade to banana adapters. You can also use pin terminators or your existing bare wire ends. . I currently use them on two pair.

Show us the terminals or name the speaker model.

I took the challenge and spent some time searching. These don't look like any AR model I can find. Three items: The drivers are wrong. The woofer resembles those used in Kef speakers and the tweeter is unlike any AR driver in the library; no AR ever had wiring directly into the rear of the speaker; the vinyl covering doesn't look right. These could have perhaps once been ARs but they have been modified beyond recognition.

For estimates to rebuild drivers send a Personal message to @RoyCand /or @Chris1this1. They can restore AR3 mid drivers and tweeters that meet threshold repair criteria. Not all mid and tweeter bodies can be restored to health. If all we can know before the purchase is the grills show no sign of removal and the cabinet integrity is not impaired I would offer no more than $300 and that is betting the woofers are cloth surround, way less if the cabs have joinery problems from moisture. I guess I am just too picky. Aadams

I have purchased old Spragues from known and trusted sellers. They work fine. If you have listened to these speakers and can't hear a problem then this cap replacement is precautionary rather than remedial. You could leave the big cans in place and replace all the smaller values. Cap replacement in working speakers is rarely a big payoff excercise.

Those are original Spragues. Crossover has not been recapped.