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ra.ra

AR amplifier: headphones, Delrama

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Speaker forum, yes, but we occasionally see posts regarding associated electronics, and I've just got a couple questions regarding the original AR amplifier. I've dug around a bit thru forum archives (perhaps not deep enough to answer my own question?) and I found the response below to another member's question almost ten years ago. Tom clearly dates the introduction of amplifier-receiver-tuner, but I'm curious about any original electronics products released after the tuner (1970) and before 1973, as noted in the reply.

1. Regarding the headphone issue, did AR produce a later release of the amplifier with the headphone jack and switch, as suggested by the attached pic? It sure looks factory original to me.

2. On page 2 of the original tech sheets for the AR amp, at the bottom there is mention of a NYC company called Delrama International. Who are they, and how were they involved with Acoustic Research?

Posted 01 June 2004 - 12:51 PM

>Did the AR receiver pre-date the AR amplifier, or were the
>tuner and amplifier released after the receiver? Why did AR
>include a headphone jack on the receiver, but not on the
>amp...I had to use one of those goofy Koss headphone boxes
>with my old AR amplifier!

The AR Amplifier was the first, and it was introduced in 1967, the same year the AR-3a made its debut. The AR Receiver was introduced in 1969, and the AR Tuner followed in 1970. AR originally felt that a phone jack for headphones was not necessary with the Amplifier, but the demand for it was answered in the AR Receiver. The last of the original AR electronics came in 1973.

--Tom Tyson

post-112624-0-83009600-1389993170_thumb. post-112624-0-91840800-1389993205_thumb.

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Never, ever saw an AR amplifier with a headphone jack, but that looks too good for an after-market mod - the lettering even matches that of the receiver.

There was a Delrama that acted as a distributor for some of the smaller US audio equipment manufacturers, but you'd think that AR would be way out of their league.

UNLESS AR didn't sell their amplifier abroad, and Delrama contracted for a run of amplifiers with headphone jacks!

Nice mystery.

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Interesting that the Delrama name was even recognized. I've glanced at this piece of literature several times before and never noticed that name, and now that I have, I'm sure I've never heard of it before.

I'm perplexed about the amp, too. Another pic attached : different amp with headphone jack and matching tuner.

post-112624-0-04975600-1390018932_thumb.

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1. Regarding the headphone issue, did AR produce a later release of the amplifier with the headphone jack and switch, as suggested by the attached pic? It sure looks factory original to me.

I have two examples of the AR Amplifier, both are the Universal model.

Of these two, the version with the lower serial number (A0227xx) does not have an output for headphones, whereas the later one (A0254xx) is replete with front panel spkr/phones selection switch and headphones jack.

post-101656-0-59818700-1390067358_thumb.

Another difference between the two amplifiers in question is regarding the AR logo printed on the front panel. The unit with the headphones jack has just "AR", the other one has "AR INC." (I have, however, also seen photographs of regular models with the plain "AR" logo, see here for example.) The pictures below are not mine, but are included for reference:

post-101656-0-84073900-1390083967_thumb.

One further external variation I've noticed is that some units have a more elaborate perforated enclosure for the rear heat sinks, as shown below:

post-101656-0-52559400-1390069781_thumb. post-101656-0-74972300-1390070265_thumb.

Robert_S

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2. On page 2 of the original tech sheets for the AR amp, at the bottom there is mention of a NYC company called Delrama International. Who are they, and how were they involved with Acoustic Research?

To the best of my knowledge, the official AR "Specifications and performance curves for the AR Amplifier" and "Specifications and performance curves for the AR Universal Amplifier" information sheets were identified as L-1609 and LIT 1610 respectively (this being printed on the lower left corner of the sheet showing the curves). There is no mention of Delrama on said documents.

It is possible that the Delrama branded (product announcement) tech sheets are not, per se, the sole 'original' AR literature — in that they may have been prepared specifically for (or by) Delrama, with reference to their own distributive/publicity purposes.

Robert_S

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Thank you, Robert_S, for the response. I had also noticed the two small distinctions you mention - - - the "INC" on the front panel, and more than one type of enclosures at the rear heat sink. To get really picky, I also noticed differences in the way the color coding is communicated at the RCA jacks.

Your confirmation about the existence of the headphone jack model affirms that my pics were, in fact, not some elusive unicorns; and your serial number authentication suggests that indeed this feature was most probably a late model design modification.

Also, your comments about the Delrama copy, although not fully authoritative, at least tend to suggest that this company really had no substantive business venture with AR, which is pretty much what I tend to believe until another voice states otherwise. This information, however, was found on the copy in the forum library, which is why it gave me pause to question any possible association between the two companies.

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Delrama was an export company that represented Acoustic Research during the 1960s and perhaps into the early 1970s. Delrama was not an AR-owned company or in any way affiliated with AR. Delrama simply represented AR abroad. AR products and service-replacement parts were handled by Delrama, and the company took responsibility of shipping, selling, displaying and servicing AR products into Europe (and perhaps other areas) during much of this period. In the early 1990s, Edgar Villchur called me to say that the owner of that export company was shutting down business and had a supply of service parts left over that he wanted to dispose of, and that these parts included crossover networks for AR-3s, AR-2axs, AR-3as and so forth, as well as service parts such as drivers. Included were several AR-4 woofers that were mounted inside a plywood shipping carton screwed together for protection, AR-3 tweeters and so forth that were also in those cartons. I contacted this individual, and I found out that he also had one of around three or four original AR-3a "cutaway" display speakers (actually fabricated in Cambridge by Sumner Bennett) that had been to Europe and back a few times for audio shows and military export shows. I offered to buy most of his old inventory -- which wasn't a great deal -- and the AR-3a Cut-A-Way (picture attached). Except for one AR-3 tweeter I sold, I still have the inventory. The price was extremely reasonable, and the products were shipped to me. I had both the AR-3a Cut-A-Way and the AR-11 "Visible" speaker on display at the 1994 AR 40th Birthday Celebration in Grand Central Terminal in New York. Both speaker were fed with a 5 Hz sine-wave signal to show the woofer pumping slowly back and forth much like the demonstrations in the AR Music Room back in the late-50s and 60s. There was an AR-3

As for the phone-jack output on the AR Turntable, I don't know the details on that iteration, but I suspect it was done for the export International market during the latter part of production. It may have been available here, but I suspect it was intended for that market. I don't have any details on that unit, but I might ask my friend Sumner Bennett (he was sales manager for AR for many years) if he remembers any details on it. The fact that the Trajan-script "AR" logo did not include the "Inc," makes me think that this update came after the June, 1972, Teledyne acquisition of Acoustic Research; after that time, the "AR Inc" morphed into "AR," without the incorporated at the end. This marked the end of the "classic" period for Acoustic Research, and a year later AR moved from Cambridge to Norwood and soon the "Teledyne AR" period began.

The difference in the back panel heat-sink portion of the AR Amplifier was the result of updates to the original design. The heat sinks exposed on the rear are the newer iteration (also most with the improved biasing network for better reliability), designed for better cooling. It was felt that the perforations obstructed the convection cooling of the output devices, thus it was improved.

--Tom Tyson

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post-100160-0-68504200-1390193610_thumb.

post-100160-0-13960900-1390193692_thumb.

post-100160-0-56800300-1390193943_thumb.

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Thank you, Tom, for yet another enlightening peek into the mystery of the history. Sounds like by the time AR had developed manufacturing facilities in England and Holland (when did that occur?), there was a need for additional support (Delrama) in the customer service and parts distribution areas that AR had already well established stateside.

Those cut-a-way speakers are so cool, as well as extremely educational, for anyone with an interest to understand all of the components and some of the phenomena that constituted the design, construction and performance of these speakers. I'd never seen that AR-11 with plexiglas before.

Just so we do not confuse any followers here, in paragraph 2 of your response, I believe you meant to say "amplifier" instead of "turntable". About the phone jack, I agree it must have been a later production modification, but I can't be sure it was only intended for foreign markets. I tend to think that since the phone jack was most probably well-received on the AR Receiver, perhaps it was just another case of "parts bin engineering", where someone said, "Hey, we got these 1/4" jacks here, people like 'em, let's add one to the amplifier." And if the jack-amps were only intended for international markets, wouldn't all of them be of the 220V variety?

Your explanation of the inclusion/exclusion of the "INC" on the AR amp front panel does seem to make good sense following a corporate timeline (Cambridge to Norwood), but would it then follow that this explanation is also the rationale why the AR Receiver and AR Tuner also had no "INC" on their front panels?

Your comments about the heat sink enclosures make perfect sense, but if a little perforated metal was creating such a problem, why didn't AR engineers just increase the metal mass in the heat sink fins?

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Oops. Yes, I meant to say "Amplifier," not "Turntable." Thanks for your clarification.

As for the phone jack output and switch on the amplifier, I suspect that AR made that change on all models after a certain date, but I'm not certain of that time period. Originally, it was felt not to be needed and to keep costs low, but I think the demand for it was there all along, and some reviewers commented on the absence of it on the amplifier. Once the AR Receiver was introduced, the headphone jack feature was included, of course, so probably after that time it was decided to push on with it. Delrama probably pushed for it for the export market; many foreign listeners insisted on headphone compatibility. AR did, however, have an early "fix" for it, but it involved adding a little switch box, wiring and so forth -- after the fact.

As mentioned earlier, the AR Amplifier was introduced in 1967, right at the beginning of Teledyne's presence at AR. The AR Receiver was introduced in 1969; the AR Tuner came in 1970. These dates would be coincident with a change to the newer Trajan script "AR" without the "Inc." So, I'm thinking that the AR Amplifier soon followed the change made in the Receiver and Tuner to use only the "AR." Perhaps the headphone jack was added at the same time the silk-screen change was made; it would make sense to do it all at once.

The AR manufacturing and design facilities in Amersfoort, Holland was opened in 1969; the facility in Bedfordshire, England was opened in 1971 about the time of the introduction of the AR-LST. With these facilities, there was actually less need for export outfits like Delrama, and I'm sure that company was phased out around this time anyway. The Delrama outfit was close to the original stalwarts at AR; i.e., Edgar Villchur, Roy Allison, Abe Hoffman, Gerald Landau and so forth.

The AR-11 "Visible" speaker was made available to AR dealers in the mid-1970s as a sales tool, and quite a few were made. I'm glad I held on to mine! There are probably a dozen or more still out there, but I've never seen one show up on the internet.

--Tom Tyson

post-100160-0-41254000-1390328862_thumb.

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I bought a pair of AR11"visible" speakers separately from two local AR dealers. All drivers except woofers were good. So I patched the missing side walls and made them whole again with my AR3a woofers. They had more extended highs and sounded more transparent them my AR3a, IMO.

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Huh?

Are you saying that you obtained two of these rare AR-11 "visible" demo speakers and then replaced the purposely dissected woofs with working 3a woofers, and also patched in the transparent side panels in order to create another pair of usable hybrid speakers? OK ..... I guess. I'll admit that I've also been known to try to give old speakers a new life with refreshed parts.

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ra.ra,

Yes indeed.I used MDF to replace the Plexiglass panels and covered the surface with 1/32" walnut veneer. I was a great fan of AR at that time. Later I used 2 pairs of AR 4" woofers and 2 Dynaudio D28 tweeters to build a pair of D'Appolito MTM's and drove them with an ADCOM 555 Mk2/Luxman TP114. This was the beginning of my DIY speaker building.

Currently I am listening to this:

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Dig those super-tweeter cabinets! :lol:

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Gentlemen:

May I add a belated postscript to your discussion? I came to this thread because, like "ra ra" and others, I have been puzzled by the occasional eBay auctions I've seen for old AR amps with a headphone jack and related circuitry. The recollections and speculations of Robert_S and Mr. Tyson especially have lifted several veils, and I thank them sincerely for doing so. My own recollections, which both supplement and slightly conflict with Mr. Tyson's, are as follows.

First, some autobiographical background. I turned 22 in 1967, when the AR amp was announced. In college I had become strongly enamored of the AR turntable and AR speakers and decided that I wanted to own them once I succeeded in mending my impecunious ways. All such thoughts were put on hold when I was drafted in July 1967, and it was several months later, while I was still in training, that I read of the introduction of the amp.

As it happens, I was shipped off to Vietnam in December 1967 for the standard tour of duty of one year—i.e., if one lived so long. Virtually the only positive thing about my service there was that the associated combat pay provided me with enough money to buy a complete AR system: the turntable, the amp, and a pair of 4x speakers. I placed the order for the equipment in November 1968 and the AR sales staff, as helpful as one could ever desire, arranged for shipment to my parents' address in time for Christmas.

The point of offering all this detail is to underline the significance of the purchase for me. As I no longer possess any of these pieces and have only one or two faded Kodak snaps of the amp, my recollections obviously have little concrete support. You may or may not take my word that I have an excellent memory, but given the autobiographical import of the circumstances, I think any reader would agree that the likelihood of my getting things right is enhanced.

Now the facts are these. The AR amp I received in December 1968 was built in the first full year of production. The logo on the left did not include the "Inc.", and the heat-sink fins were exposed, not caged.*[but see addendum below.]* Of course, there was no headphone jack. I know that these descriptions seem to contradict the far more authoritative ones of Mr. Tyson, but no disrespect is meant. I am simply reporting what I experienced. Indeed, over the 21 years I possessed and used the amp, it underwent some half-dozen "repairs" at factory-authorized facilities in New York City (the sneer quotes are there because several repairs were clearly bungled). During the many hours I spent at these shops, I saw a dozen or more AR amps sitting on visible shelves. All of them lacked the "Inc." on the front, and of those whose back I could see, none had a cage.

I gave the amp away—to a very pretty girl [sigh] with whom I worked at the Metropolitan Opera—largely because (1) I needed more inputs than the amp offered (thereby hangs a tale of the AR SRC that can wait for another day) and (2) having just then bought a new Teledyne AR A-06 amp—which seemed to me then to be an order of magnitude superior to the old amp in every respect (it still does)—I no longer felt the need to keep the amp for old times' sake. Given the prices old units now get on eBay, how I wish I had!

I thank the moderators for allowing me to offer my reminiscences.

_________

P.S. I still have the ancillary paperwork included with the original AR amp. It does not include the Delrama line at the bottom.

October 17, 2015, addendum. I located one of those old Kodak snaps I mentioned above. Though it's badly faded and shows the AR amp only from an angle, with a magnifying glass I can see a linear red smear at the right of the AR logo. In other words, I was dead wrong in writing above that the logo lacked the "Inc." (What was that I said about my memory?) At least I was right about the heat sink.

Pardon me for stopping here, but there's a plate of crow waiting on the table, and bitter experience has taught me that it tastes even worse cold than warm!

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Fascinating post, Claudel.

I wonder how many guys have very similar stories?

And I laughed when reading your account of the old factory service center in NYC.

I once contacted them about a blown AR-2ax woofer, and was assured that if I brought the speaker into the shop, they'd be able to replace the woofer while I waited.

The location was in lower Manhattan, across from the WTC construction, and parking was non-existent; so I had my then-girlfriend circle the block for about two hours while the repair shop did its thing.

I endured a lot of criticism heading south on the Turnpike, and it became clear that she was not the girl for me!

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Dear ar_pro,

Thanks for replying; your comments really struck a chord. If tomes haven't been written about the problems that come with the interaction of a passion for audio and the female of our species, they bloody well ought to have been. Of course, the question of who would read them remains unanswered.

I didn't have a car back in those days, which hardly seem more than a year or two ago. I got to that repair place via the subway; the one-way trip from the Bronx was 55 minutes, barring delays. The carrier I used to transport the amp (I still have it) consisted of a triple thickness of oversized heavyweight paper shopping bags, with masking tape reinforcing the top and securing the three handles on each side to one another. Fortunately I was well aware of the need to make the trip only on rain-free days!

Last but not least, please note that photographic evidence has forced me to edit my earlier comments in an important detail. If this experience teaches me to insist less on the incomparable excellence of my memory, it will have done me a good turn.

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Now the facts are these. The AR amp I received in December 1968 was built in the first full year of production. The logo on the left did not include the "Inc.", and the heat-sink fins were exposed, not caged.*[but see addendum below.]* Of course, there was no headphone jack. I know that these descriptions seem to contradict the far more authoritative ones of Mr. Tyson, but no disrespect is meant. I am simply reporting what I experienced. Indeed, over the 21 years I possessed and used the amp, it underwent some half-dozen "repairs" at factory-authorized facilities in New York City (the sneer quotes are there because several repairs were clearly bungled). During the many hours I spent at these shops, I saw a dozen or more AR amps sitting on visible shelves. All of them lacked the "Inc." on the front, and of those whose back I could see, none had a cage.

I thank the moderators for allowing me to offer my reminiscences.

_________

P.S. I still have the ancillary paperwork included with the original AR amp. It does not include the Delrama line at the bottom.

October 17, 2015, addendum. I located one of those old Kodak snaps I mentioned above. Though it's badly faded and shows the AR amp only from an angle, with a magnifying glass I can see a linear red smear at the right of the AR logo. In other words, I was dead wrong in writing above that the logo lacked the "Inc." (What was that I said about my memory?) At least I was right about the heat sink.

Pardon me for stopping here, but there's a plate of crow waiting on the table, and bitter experience has taught me that it tastes even worse cold than warm!

Claudel,

I just now read in detail your post from back in October and your interesting story about Vietnam and your AR Amplifier, AR Turntable and a pair of AR-4x loudspeakers. What you had was a excellent combination that was pretty much unsurpassed for a small but very accurate sound-reproducing system! To this very day there aren't many systems that size that would sound better! Overall, I don't see that we're in too much disagreement, but I think I can see some discrepancies in dates, etc.

The AR Amplifier was definitely introduced at the New York High Fidelity Music Show in October of 1967, but it is true what you say that the first full year of production was 1968. If you got your amp in December, 1968, it was well into production with many thousands of units having been produced, and your unit was by no means an early version. I'm pretty confident that first production commenced about that time of its introduction in 1967, as the amplifier had been pretty carefully sorted out and tested for several months leading up to its introduction. There may have been some delay, but not much. AR was eager to get it into the hands of dealers worldwide.

The first AR Amps definitely had the closed-in perforated screen that covered the heat sinks, and the amp had adjustable bias and several other things that were changed later on. The first AR amps did, of course, have the "Inc" printed on the front panel beside the "AR" inscription. This changed to "AR" at some point after the amp went into production because there was no more "AR, Inc." after 1967. It was simply "AR" and then "Teledyne AR." AR was sold to aerospace company Teledyne, Inc., in June of 1967. I suspect that when the stock of "AR Inc." plates ran out, all new ones were printed with simply "AR," but this may have been well into 1968.

Early AR Amplifiers had a tendency to overheat (although some soldiered on indefinitely while the back of the case would get so hot you could not touch it), and many went into failure mode and would blow out the output fuses, etc. Those who foolishly over-rode the protection fuses would find huge dc-offset in the output, which would fry any woofer's voice coil and "freeze" the woofer in place. That's another story, but it was not uncommon, and this failure happened to two of my early amps driving my AR-3 loudspeakers. AR took care of everything, of course, and I suffered no damage to the 3s.

To improve the heat-sink heat dissipation, the screen cage was pulled back away from the heat sinks to allow better air flow, and this helped the amp run a bit cooler (though AR Amps always dissipated a lot of heat once running along). This happened sometime in 1968, but I'm unsure of exactly when it occurred. I've attached some images that may clarify this situation. Note, too, that unless you bought your AR equipment in Europe of Asia (not the US commissary), you would not have come in contact with Delrama, Inc., the AR exporters of equipment prior to AR's UK and Holland plants.

post-100160-0-99868100-1448686832_thumb.

This is an original "file" photograph taken of the Amplifier before it was officially introduced in 1967. Photo was consigned to me.

post-100160-0-22985100-1448686858_thumb.

This shows a close-up of a rather battered early version (#131) AR Amplifier made around November, 1967.

post-100160-0-00628300-1448686973_thumb.

Shows the "AR Inc" on the front panel. This was used until well into 1968 or perhaps 1969, but probably after stock was depleted of old units.

Thanks,

—Tom Tyson

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post-116698-0-55352500-1449081834_thumb.post-116698-0-19420600-1449082046_thumb.post-116698-0-02713500-1449082128_thumb.post-116698-0-47616700-1449082204_thumb. My father bought this AR Amplifier , perhaps in 1969 , it's a 220 V version made for European sales and it' s still in use . Mine hasn 't headphone jacks, and has the AR inc. logo. A good amp, warm and good sounding, and very dynamic ! Best wishes, Adriano

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I wish I still had my AR amp. It was an early one without the headphone jack. It quit working long ago and I never got it repaired. Not sure what happened to it. It sat around for a long while and likely got trashed when I moved one time. Sad, I always liked it for it's utilitarian simplicity.

der

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On 11/28/2015 at 0:10 AM, tysontom said:

Claudel,

I just now read in detail your post from back in October ….

Thanks,

—Tom Tyson

 

Dear Tom (if I may),

I now regret that I stopped following this thread before I saw your wonderful comments of 19 months ago. Not only are they a pleasure to read, but they answer several long-lingering questions—and several others that dropped unnoticed by the wayside in half a century of living. What it says about folks like us who dwell on the technology of yesteryear I leave to more "practical" (often = romance-free) men to decide!

With much gratitude,

Tom McCarthy

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Had the AR turntable in high school, wanted the amplifier too, but it was beyond reach back then.  Renewed interest, found a nice one a couple years ago, had a case made for it.  Plywood a bit too thick, but looks fine, IMO.  Enjoy spinning records on the weekends.  Driving a pair of AR-91s.

IMG_20171109_111149.jpg

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Beautiful.

That's the best-looking amplifier faceplate I've seen since these were new!

Nice job on the reproduction sleeve, too; it really captures the look of the original walnut enclosure.

 

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I owned one without the headphone jack. At the time I did listen quite a bit to headphones since we had a new baby. I had to add a stand alone headphone jack/speaker switch to do so. Many years later one channel went out on the amp and I pitched it. I've been kicking myself every since for doing so. Cosmetically, it was pristine with the wood enclosure. Love to have it back.

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No headphone jack in this one, but last night I was reading an outdated New Yorker magazine and spotted this AR amplifier in a laudatory review of the work of avant-garde performance artist, Charlotte Moorman.

moorman 1.jpg

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