stands for the lst

[fred]

i just bought ( for €600!) a splendid pair of lst speakers with only some minor scratches, never been opened and from the original owner! all the units are fine, only the woofers need to be refoamed, but i placed, for the time being, the woofers from a pair of ar 3a-improveds (ca 1975) in them and they sound superb!!

i have a few questions about them; the serialnumbers are hl 2709 and hl 2710, one woofer has this code on it; 401-155, 4 ohms ar. the backsides look a bit different than the ones i saw on the internet, there is no circuitboard visible nearby the banana inputs.

my first question; how old are they and were they perhaps made in europe; the attached leaflet indicates the ar adress in the netherlands??

what kind of stand should they be placed on; i'd like to put them free from walls and use kef b139 woofers mounted in the floor of the listeningroom as subwoofers via nakamichi electronic crossover filters.

everytime i read story's of capacitors that are kaputt! after all those years ,but this pair (imho) sounds excellent!! ( and both speaker sound the same given a double mono signal), is it possible that everything is ok?

did i pay to much?????

and last but not least: they came without ar lst-logo's...so i need a pair of those!!

[KlausDK]

i just bought ( for €600!) a splendid pair of lst speakers with only some minor scratches, never been opened and from the original owner! all the units are fine, only the woofers need to be refoamed, but i placed, for the time being, the woofers from a pair of ar 3a-improveds (ca 1975) in them and they sound superb!!

i have a few questions about them; the serialnumbers are hl 2709 and hl 2710, one woofer has this code on it; 401-155, 4 ohms ar. the backsides look a bit different than the ones i saw on the internet, there is no circuitboard visible nearby the banana inputs.

my first question; how old are they and were they perhaps made in europe; the attached leaflet indicates the ar adress in the netherlands??

what kind of stand should they be placed on; i'd like to put them free from walls and use kef b139 woofers mounted in the floor of the listeningroom as subwoofers via nakamichi electronic crossover filters.

everytime i read story's of capacitors that are kaputt! after all those years ,but this pair (imho) sounds excellent!! ( and both speaker sound the same given a double mono signal), is it possible that everything is ok?

did i pay to much?????

and last but not least: they came without ar lst-logo's...so i need a pair of those!!

Hi Fred

Excelllent price, with all drivers original and in working condition, I would say you've got a bargain price; 600€ is less than 1000 US$.

LST's plays their best with their back close against the wall.

Regarding age, take a close look at both woofers, there is usually some kind of a time stamp. If the cross-over is not accessible from the back, I would say it indicates that your speakers are later production. Pictures would help, especially of the crossover, what caps are used?

I would recommend to replace the 6 uF for the tweeters and the 40 uF for the mid-range's, since they might have drifted and changed the x-over frequency.

I know TT has designed stands for LST's maybe he will chip in with a picture and measures.

Logo plates is obtainable at Larry/Vintage-AR, you can find him on ebay dot com.

Congratulations on the find.

Klaus

[tysontom]

Hi Fred

Excelllent price, with all drivers original and in working condition, I would say you've got a bargain price; 600€ is less than 1000 US$.

LST's plays their best with their back close against the wall.

Regarding age, take a close look at both woofers, there is usually some kind of a time stamp. If the cross-over is not accessible from the back, I would say it indicates that your speakers are later production. Pictures would help, especially of the crossover, what caps are used?

I would recommend to replace the 6 uF for the tweeters and the 40 uF for the mid-range's, since they might have drifted and changed the x-over frequency.

I know TT has designed stands for LST's maybe he will chip in with a picture and measures.

Logo plates is obtainable at Larry/Vintage-AR, you can find him on ebay dot com.

Congratulations on the find.

Klaus

Hello Klaus,

I have used two different stands for my various pairs of LSTs over the years. The first stands were designed to get the LST up off the floor but placed close to the front wall -- as well as protect the speaker. These were made from Mozanbique and Aframosia wood, which happened to be handy at the time, but could be made from any fine wood. The other stands were designed to place the speaker on a wall, which I used for several years. These stands were made from medium-density particle board, epoxied and screwed, thick and very heavy, and were designed to be fastened to a wall.

--Tom Tyson

[loudbuff]

The best stands for a pair of AR-Lst is another pair of AR-Lst! (Preferably with the drivers removed, holes plugged, and filled with fine grain sand) Looks good too!

No kidding.

[dynaco_dan]

The best stands for a pair of AR-Lst is another pair of AR-Lst! (Preferably with the drivers removed, holes plugged, and filled with fine grain sand) Looks good too!

No kidding.

Hi there

Funny thing is Tom"s posting yesterday had 4 nice photos at the end.

What is that saying, here today, gone tomorrow. LOL

My bros made a pair for his LST's.

The base was square, about 12" x 12".

The top was the same shape as the LST cabinet.

The height allowed the tweeters to be at about ear level when sitting in a chair.

I hope to take a photo and post it here in the future.

[fred]

Hi there

Funny thing is Tom"s posting yesterday had 4 nice photos at the end.

What is that saying, here today, gone tomorrow. LOL

My bros made a pair for his LST's.

The base was square, about 12" x 12".

The top was the same shape as the LST cabinet.

The height allowed the tweeters to be at about ear level when sitting in a chair.

I hope to take a photo and post it here in the future.

Hi dynaco dan: do you think that a dyna stereo 400 would be the right amplifier for my lst's??

[dynaco_dan]

Hi dynaco dan: do you think that a dyna stereo 400 would be the right amplifier for my lst's??

Hi there

Of the more reasonably priced old classic amps, the Stereo 400, Double Dyna 400 and the Stereo 416 would be geat choices, in that order.

Lot's and lot's of clean power for more dynamic listening sessions.

The Stereo 120 would be ok only for lower level listening.

The LST's in particular, requires a very stable amplifier with suffciient reserve power to support the very high woofer impedance as well as the demanding tweeters.

Whereas a lower powered amp will allow you to listen to music, etc, you must keep it from clipping and destroying the drivers, particulary the weaker tweeters.

The original recommended 2 amp FNM fuse is maybe a little oversized for safety today, perhaps slight downsizing them might be a great idea.

[dynaco_dan]

Hi there

Of the more reasonably priced old classic amps, the Stereo 400, Double Dyna 400 and the Stereo 416 would be geat choices, in that order.

The original recommended 2 amp FNM fuse is maybe a little oversized for safety today, perhaps slight downsizing them might be a great idea.

Hi there

While on this speaker topic, I have found that these FNM fuses now retail for $9 - $10.00 each for just one fuse.

There may be surplus stock available at a discount, check out the internet.

Great care must be used removing and installing fuses, I have found that in soldering the fuse clips to the circuit board, the heat has caused the fuse clips to break off at their base.

An adapter clip can be made from the screw type bases available as NOS units.

All one needs to do is drill out the rivet and use that clip by drilling out the soldered clip and use a small brass macnine screw and lock washer and drill a small hole through the original soldered base, do not solder.

At least this setup won't be as vulnerable to breakage.

[tysontom]

Hi dynaco dan: do you think that a dyna stereo 400 would be the right amplifier for my lst's??

I used a Dyna Stereo 400 with my LSTs for a short period, but eventually the amplifier failed. It even had the fan kit on one end of the heat sink! Granted, I was playing the speakers at high-sound levels, and this is something you probably would not do today with these speakers due to their age. One entire channel self-destructed, and I ended up selling the amp for spare parts. After that, I upgraded to a McIntosh MC2200, and it never had any problems. Eventually, I traded the 2200 for a MC2500, which I found to be the best combination. At one point I used two LSTs per channel in parallel, driven by the big Mac, and although the fans would run pretty furiously at times and the amp tripped a 15-amp A/C breaker several times, it never gave any problems. The bottom line is that the LST presents a very difficult load to many amplifiers, so big power and high stability are required of the amp.

By the way, the Dynaco ST-120 was a fine amplifier design for 8-ohm speakers, but it was never rated for 4-ohm operation, let alone capacitive-reactive, low-efficiency and low-impedance loads such as the AR-LST. Early versions of this amp could be unstable, but modifications later on improved this aspect of the design. The LST gets below 3 ohms in places, so the ST-120 should not be used with this speaker unless the output level is kept very low.

--Tom Tyson

[KlausDK]

Hi there

Of the more reasonably priced old classic amps, the Stereo 400, Double Dyna 400 and the Stereo 416 would be geat choices, in that order.

Lot's and lot's of clean power for more dynamic listening sessions.

I would second Tom on his concerns regarding the ST-400, I do not think it has the current capacity to drive the LST's. The Double Dyna 400 and the Stereo 416 (which i sessentially the same amps) has twice the number of output transistors, and therefore a much better power handling capacity.

I use a Hafler DH-500 MOSFET amp, the Hafler XL-600 would be an even more powerful choice.

Electronic Surplus still have FNM2 fuses for 2$ each, 51 left: Surplus

BRgds Klaus

[dynaco_dan]

Electronic Surplus still have FNM2 fuses for 2$ each, 51 left: Surplus

BRgds Klaus

Hi Klaus

Thank you for posting this valuable fuse source website.

[mocmoon]

Hi,

Attached is a photo that show my LST on stands that made of solid Iron wood and solid steel. Over 150lbs per stand.

I bought these LSTs last year with help from Tom Tyson. Thank you again, Tom.

For almost a year listening to these LSTs, I've never felt satisfied with its sound, especially when compared to my AR-9. Until few days ago when I checked inside the cabinets and found some bad caps (see photo). After changing the caps. Everything is great, much better bass with clear high and mid. I urge you to check to make sure all the caps are within their tolerance. Nothing worse than a bad cap.

Viet Anh

[Mexicomike]

Re power -

I have used two different Amps with good results and totally different sound. Currently I am using a McIntosh 7270 (270WPC) which has no trouble at all driving my LSTs to any level I can stand. I also use my Moscode 600 (300WPC) which also does a nice job with them. The Moscode is more "musical" sounding if that makes any sense (tube front-end, Mosfet power end) and I fell in love with its sound back in the '80s. I'm sure many folks will claim it isn't accurate and that may be but it sure makes wonderful noise!

I use the Mc primarily because it's more convenient - instant on as opposed to a delay and the fact that the Moscode has a cooling fan that can be obtrusive at background-music levels. I suppose it may be sacrilege to use LSTs for "background" music but that is the case a lot of the time for me.

At moderate volume levels, my old AR amplifier (60WPC) does a nice job and it is the primary driver for my AR3As which, because they are in a rather small room, don't really need much power to get plenty loud.

[frankmarsi]

Re power -

I have used two different Amps with good results and totally different sound. Currently I am using a McIntosh 7270 (270WPC) which has no trouble at all driving my LSTs to any level I can stand. I also use my Moscode 600 (300WPC) which also does a nice job with them. The Moscode is more "musical" sounding if that makes any sense (tube front-end, Mosfet power end) and I fell in love with its sound back in the '80s. I'm sure many folks will claim it isn't accurate and that may be but it sure makes wonderful noise!

I use the Mc primarily because it's more convenient - instant on as opposed to a delay and the fact that the Moscode has a cooling fan that can be obtrusive at background-music levels. I suppose it may be sacrilege to use LSTs for "background" music but that is the case a lot of the time for me.

At moderate volume levels, my old AR amplifier (60WPC) does a nice job and it is the primary driver for my AR3As which, because they are in a rather small room, don't really need much power to get plenty loud.

11-14-10 10 PM EST

However, concerning low power usage/low listening levels, well I'm listening to "Erich Kunzel" on Telarc CD as I write (I have several and I'm buying more tonite, plus vinyl from the same label) and it's at low levels, and I gotta just add my old 67 wpc total Dynaco ST-120 could never deal with such levels, low or high, it's not an amp peeps prefer to speak of, and I can vouch. You might know that Telarc discs are and can be quite power demanding as AR's are, to use the old hi-fi mag. term 'Head-Room". What's the expression, good-in, good-out? On my LST's that generally means loads of watts at any given time. In my last post I mentioned Telarc's cd's even though I'm a vinyl-nut, I immensely enjoy cd quality also and I admit to them needing much power as these Telarcs demand by sheer virtue of their wonderful recording quality. Any- AR owner can really benefit from listening to the whole catalog of Telarc's high-quality and delightful recordings whether it's cd or vinyl disk. And certainly if you're a classical and or movie theme and or 'thrilling' music fan. I buy'em used and new, then scrub 'em up and relish the experience. Hey, I better go buy some of their stock sounding like I am.

I would like to add that I only use AR's because I really consider music as one of my most beloved aspects of life itself!

FM

P.S. (what else?), I've tried and continue to do so; many variations with fans on amps, from DC quiet low volume ones to what I use presently those good ones, (forgot their name) built for the 'pro-world I always buy low-noise/db. with the highest 'CFM's' for which I have looked far and wide. I generally use obviously; low noise/moderate volume fans (4.75 inches) used for high power levels and even have had smaller low noise DC versions 'strapped' (2 1/2 inchers) to them which I used for lower amp output when the amp is simply at idle with-out any signal. For me it's always been a complete system concern, power, pre-amps, cables, cartridges and cartridge leads, vinyl cleanliness, turntable accessories the usual 9 yards. I guess I'm a real 'hobby-ist', even though my efforts these last few years have been minimal. I know there are many others who will shame me in their efforts and level of energy. I do it all on a meager budget and my systems don't cost anywhere near what one sees in TAS or the St-Phile mags of course, just vintage stuff from the 'Golden-Age', however if one were to equate dollar levels from then to now , the component prices would prove interesting if nothing else. Nonetheless my systems can and astonish most with absolute musical enjoyment as they do for me even if they're not super hi-end.

FM

P.S. 2 (what-da?) In terms of amps sounding different from one another, big schools of thought there fur-sure! As some may know of, I'm a dyed in the wool Phase Linear guy, watts vs. dollars and after a number of months now I can say that my two 'over-rebuilt' Series Two PL-700 seem to have a ever so slightly less 'fat' bass than my PL-400's 'un-touched' ones do, of course the bigger amps handle higher peaks and so forth with a slightly more satisfying ease and of course it's not only about power ratings watt for watt, there's resolution, etc. etc. When I went from a Dynaco ST-35 to an ST-120 the differences in over-all 'big-ness' of sound were most gratifying, the 120 seemed faster, but again, you know tubes vs. S.S., another can of worms there. When I switched to a PL-400 in '74, I never looked back even though I appreciated each amp for what they were, I will never return to low power except for the novelty of doing so with maybe a pair of 4ax's. In cars, I like a big ole' V-8 compared to any high-tech V-6, lets call a spade a spade. Just a little non-related trivia here; most peeps don't know that Buick came out with the first aluminum V-6 in '61 or so, for their compact Special platform, long before anyone. It didn't receive much public acceptance with all those big 8's running around at the time and Buick put it on the back shelf after dismal sales figures. Range-Rover offered to buy the patents/blue-prints and back then even took some 'dies' and with 'mods' has pretty much used it ever since. Go figure? Gee, that's kinda like Levinson with the LST/Amati, the Carver replicating C.J. and others tonality/sound quality- challenge/experiment with a mag. thing, vintage PL's almost looking like early '60s Marantz stuff and M.L. Palette stuff and the like kinda looking like early PL. I guess there might not be anything new under the sun, what about us guys who cling to our stuff? Life is good for us about that, no?

Long LIve Vintage AR's!

[Mexicomike]

PL 400 was my first "big" amp. THen had several Carvers - including his 4000 pre amp with the auto-correlator, etc. But when I auditioned the Moscode in our house for a week in the mid-80's, that was my first real "aha" moment with an amplifier. So I've had it ever since - had a few "upgrades" to it performed by George Kaye, who originally designed it for New York Audio Labs. I bought the Mc stuff in the early 90s because I always wanted Mc stuff! The amp is great but the preamp , a C34V, has a channel go out periodically. I sent it back to Mc and they fixed it for free but it's done that 4 times since then. Turns out it's just one of the connectors between two circuit boards. Have to open up the preamp and clean/remake that connection. Old point-to-point soldered hard wiring doesn't have that problem...

Had a Conrad Johnson tube pre and and hated it. I thought it was very harsh and glaring sound wise. I literally could not listen to it for extended periods. I GAVE it to a friend a few years ago.

Re power. I found that with my LSTs with the Mc stuff playing typical rock/pop, and the volume in the room at a moderate level - too loud for normal conversation but not LOUD level, the Mc's power needles are mostly showing not more than 3 WPCs! However, on the Telarc 1812 LP, with the amp showing average power levels of around 10WPC, the cannon shots will engage the automatic clipping circuits on the amp, at 270WPC...