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Harvard Electronics H-1 OTL Amp

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Posted on February 12, 2016 at 11:10:08
mrflex65
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Location: N.C.
Joined: June 16, 2012



Greetings!
Came across this Harvard H-1 OTL amp on a local area Craigslist for little money.It's complete but it appears to be missing the badge that was glued in place on the brass colored trim.I understand that this particular model seems to be pretty rare.Thanks go out to Pera Peric for providing much needed info for this piece of history!

 

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RE: Harvard Electronics H-1 OTL Amp, posted on February 12, 2016 at 11:11:57
mrflex65
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Another pic....

 

RE: Harvard Electronics H-1 OTL Amp, posted on February 12, 2016 at 11:13:59
mrflex65
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One more.....

 

RE: Harvard Electronics H-1 OTL Amp, posted on February 12, 2016 at 13:16:56
Lew
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Location: Bethesda, Maryland
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 Spectacular! JF is for Julius Futterman, of course. I actually have a hand-written set of instructions for biasing my H3aa's, sent to me by Julius, and I recognize the handwriting. He was a nice guy. Whatever you do to restore the function of the amplifier, don't eradicate that note.

 

RE: Harvard Electronics H-1 OTL Amp, posted on February 13, 2016 at 05:10:19
Banat
 Congratulation ! it is really nice find ,

It is first time for me to have the chance to see pics of that ultra rare H1 OTL amp in decent resolution , thanks for upload ,
There is some opinions around that H1 is best sounding OTL amp that Julius Futterman designed ,
It looks that your amp is in decent condition having in mind how old that unit is ,
on the first look tubes appears to be in OK condition , only by judging how wide and shine tubes top getters is , anyway tubes real condition have to be checked separately from very qualified person .

Best Regards!


 

RE: Harvard Electronics H-1 OTL Amp, posted on February 13, 2016 at 06:01:59
mrflex65
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Location: N.C.
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 Trust me, i have no intentions of cleaning that bottom panel!Since you pointed it out,it just dawned on me that those are Futterman's initials!Since then,the output tubes have been changed,a few of them are still the originals,the rest are a mishmash of Raytheon's and newer logo RCA's and uses a 6AN8 driver/phase splitter tube.If i may ask,what was Futterman's association with Harvard? Did he work at/owned the company or did he just license the design to them.From what i read,Harvard went under in the early 60's.Can't find a thing on them on the net......

 

RE: Harvard Electronics H-1 OTL Amp, posted on February 13, 2016 at 06:09:51
throwback
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 Back in about 1979 Julius made me a direct-drive amp to power my STAX SRX ESL headphones. I don't know if it is one of a kind or not. JF also hand-drew the schematic for me. (You're right, Lew: he was a nice guy.) The combo is still sensational. I will never part with the amp or the schematic. Call me sentimental . . .

 

RE: Harvard Electronics H-1 OTL Amp, posted on February 13, 2016 at 06:29:36
mrflex65
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 Banat,your welcome! All the output tubes check fine,one of them has lost most if not all of the getter flash.The input fuse has blown,but doesn't appear to have been a "catastrophic" event.All the fuses look to be original to the amp as well.The person i bought this from cleans out old houses and this is what he found....

 

RE: Harvard Electronics H-1 OTL Amp, posted on February 13, 2016 at 07:21:07
AJ
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That is a really nice find.

I have the H3 Stereo model. These work really great on Quad Esl's

Harvard Electronics built these under license for Futterman.



 

RE: Harvard Electronics H-1 OTL Amp, posted on February 13, 2016 at 08:06:49
Banat
 mrflex65

I think that 12B4A power triode which looses almost all getter have to be replaced with fresh one , just to attain future stable balance of output SEPP power stage for next period of amp use ,
but there is so many other things that have to be Very Very Carefully checked and examined before that old H1 will be again in power on condition , and ready for use , it is so old ,
and check that old power cable since from your pics seems to me that it is in not so good condition at place of trough chassis input plastic receptor ,
and if is possible add some more pics , especial from under the chassis ,
and one question , did that person from which you have bought this amp have maybe one more H1 ? , since it will be cool to find another one for your stereo system use ,
anyway is great thing that you have recognized and saved very significant piece of audio amp history .


 

RE: Harvard Electronics H-1 OTL Amp, posted on February 13, 2016 at 09:17:01
Lew
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 Harvard Electronics was Julius' company, just as Atma-sphere is Ralph's.
Why he chose that name, I do not know. Perhaps he was a Harvard graduate, but I think he may have been an immigrant to the US, which does not rule out that he may have gone to Harvard. As an adult, he was definitely a New Yorker.

 

RE: Harvard Electronics = Futterman, posted on February 13, 2016 at 09:19:00
Lew
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 I believe he founded and owned the company. Later, after Harvard Electronics formally went defunct, he continued to build the very same amplifiers under the name Futterman, but those bore no logo, at least not the ones I have ever seen.

 

RE: Harvard Electronics H-1 OTL Amp, posted on February 13, 2016 at 09:22:38
Lew
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 Perhaps a coincidence: In 1979, he made me a pair of H3aa monoblocks. When I went to his "factory" (one or two rooms on 72nd St, west of Broadway by a few hundred feet) to pick up my amplifiers, he was building an OTL headphone amplifier for someone. He was rather excited about it and showed it off to me. I have to wonder whether that was your amp, Chuck.

He made his own transformers, and the place reeked of tarry odors, probably toxic.

 

RE: Harvard Electronics H-1 OTL Amp, posted on February 13, 2016 at 12:58:49
throwback
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 LEW, wouldn't that be amazing!
I never visited JF's "factory," but I had a number of very pleasant conversations with him

 

RE: Harvard Electronics = Futterman, posted on February 13, 2016 at 13:51:05
AJ
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 Lew if you've actually met Futterman then you know better than I. My understanding from the reading I have done including the partisan book by Rosenberg I have on hand is that both Harvard Instruments and Tech Instruments were contractors to Futterman under licencse.

 

RE: Harvard Electronics = Futterman, posted on February 13, 2016 at 16:41:54
mrflex65
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Sorry guys, it's been a long day today.Here are some pic's of the bottom.
Thanks for all the info,it clears up a lot of questions about this amp.

 

RE: Harvard Electronics = Futterman, posted on February 13, 2016 at 16:44:35
mrflex65
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Location: N.C.
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Pic

 

RE: Harvard Electronics = Futterman, posted on February 13, 2016 at 16:45:05
mrflex65
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Posts: 20
Location: N.C.
Joined: June 16, 2012



Pic

 

RE: Harvard Electronics = Futterman, posted on February 13, 2016 at 16:45:51
mrflex65
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Location: N.C.
Joined: June 16, 2012



pic

 

RE: Harvard Electronics = Futterman, posted on February 13, 2016 at 16:46:27
mrflex65
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Location: N.C.
Joined: June 16, 2012



Pic

 

RE: Harvard Electronics = Futterman, posted on February 13, 2016 at 16:47:17
mrflex65
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Joined: June 16, 2012



Pic

 

RE: Harvard Electronics = Futterman, posted on February 13, 2016 at 16:47:48
mrflex65
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Joined: June 16, 2012



Pic

 

RE: Harvard Electronics = Futterman, posted on February 13, 2016 at 16:48:18
mrflex65
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Pic

 

RE: Harvard Electronics = Futterman, posted on February 13, 2016 at 16:49:29
mrflex65
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Joined: June 16, 2012



Pic

 

RE: Harvard Electronics = Futterman, posted on February 13, 2016 at 16:50:11
mrflex65
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Joined: June 16, 2012



Pic

 

RE: Harvard Electronics = Futterman, posted on February 13, 2016 at 16:51:06
mrflex65
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Joined: June 16, 2012



Pic

 

RE: Harvard Electronics = Futterman, posted on February 13, 2016 at 16:52:35
mrflex65
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Joined: June 16, 2012



Pic

 

RE: Harvard Electronics = Futterman, posted on February 13, 2016 at 16:53:41
mrflex65
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Joined: June 16, 2012



Pic

 

RE: Harvard Electronics = Futterman, posted on February 13, 2016 at 16:54:14
mrflex65
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Pic

 

RE: Harvard Electronics = Futterman, posted on February 13, 2016 at 16:59:29
mrflex65
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 Sorry about the resolution on some of the pics as i don't have the greatest camera in the world.I wonder how many Futterman made of the particular model?

 

RE: Harvard Electronics = Futterman, posted on February 13, 2016 at 17:36:55
AJ
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 Hi there,

I think I have a review of this amp in my Harvey Rosenberg booklet that he put out on OTL amplifiers.

You have some work to do. Looks like a selenium rectifier and all the caps need to go. Wiring and sockets need a going over as well as the resistors---- all of it!

Good luck, if the transformer is good, you should have a very nice amp on your hands.

 

RE: Harvard Electronics H-1 OTL Amp, posted on February 14, 2016 at 06:47:43
Banat



I believe that this schematic is very close to Harvard Electronics H1-OTL amp,it is extracted from oct.1956 article ,
-A Practical Commercial Output Transformerless Amplifier - by Julius Futterman .

 

Reason to believe I am incorrect..., posted on February 14, 2016 at 09:31:24
Lew
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 In this paper, translated from the German and perhaps as anecdotal as was my account, it is said that indeed Harvard Electronics and even another company on Long Island named "Tech Instruments" built the early production amplifiers at one time or another, under contract. By the time I met JF and purchased consecutively two amplifiers from him, HE was not involved. JF was making the amplifiers himself to order in the shop described earlier by me, off Broadway on 72nd St, and also described here. (You have to scroll to the English translation on p. 13.) Somewhere in my dim past, someone else gave me to believe that Harvard Electronics had been started and owned by Julius; maybe not.

 

I've read that the 12B4A is amazing, posted on February 15, 2016 at 01:26:13
Cousin Billy
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 After finding a stash of these tubes at a garage sale, and buying them, I thought I better find out what they where.

After much internet searching, very little was found. What I did find, was that anyone who build a pre amp with them, called them amazing.

If memory serves, one builder called it the 2A3's equal.

Anybody here have experience?

 

RE: I've read that the 12B4A is amazing, posted on February 15, 2016 at 11:16:48
Lew
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 I don't off hand know the specs of the 12B4, but I think it was used as a driver tube in some of the revered Marantz amplifiers, 8B and/or 9. It also may be used in early HK Citation tube amplifiers. This suggests it has a relatively low output impedance when used as a driver, which is also good for an OTL. Believe me, JF was a pragmatist. If he used the tube early on, it's because he could get them, and notice that he paralleled ten of them to get something like 10 or 30W (I forget which). Later, when because of TV the power beam tubes like 6LF6 came around, he switched to them probably because more bang (power) for the buck.

 

RE: I've read that the 12B4A is amazing, posted on February 15, 2016 at 12:47:50
AJ
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 No Marantz amp ever used the 12B4 input tubes or drivers. Marantz utilized 12ax7 and 6cg7 in the Model 2 and 6BH6 and 6CG7 in the Model 5 and 8B

12B4 is a medium mu triode which was used in tv sets for vertical deflection circuits

Tubes like the 6FW5 and 6FL6 were sweep tubes in horizontal deflection circuits for tv with significantly higher current capability


All of these were used in Futterman output circuits.

 

Thanks for the correction,.., posted on February 15, 2016 at 15:10:12
Lew
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Location: Bethesda, Maryland
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 What about the Citation 2 amplifier?
I didn't bother to look up the 12B4 and should have.

 

RE: Thanks for the correction,.., posted on February 15, 2016 at 16:04:19
AJ
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Hi there,

The Citation II uses a pentode input 12BY7, in a very wide bandwidth design.

It is a good push pull amp - not my absolute favourite. I can see why some may really like it.

Some of these amps in a vintage set up playing with the Quads prior to my listening room being built.... the Futterman is on the bottom shelf- the Citation on the top.

I plan to try the Futterman on the Beveridge panels see what happens ....

Thanks.

 

RE: Thanks for the correction,.., posted on February 15, 2016 at 16:04:44
AJ
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Posts: 532
Joined: February 24, 2001







Hi there,

The Citation II uses a pentode input 12BY7, in a very wide bandwidth design.

It is a good push pull amp - not my absolute favourite. I can see why some may really like it.

Some of these amps in a vintage set up playing with the Quads prior to my listening room being built.... the Futterman is on the bottom shelf- the Citation on the top.

I plan to try the Futterman on the Beveridge panels see what happens ....

Thanks.

 

Beveridge?, posted on February 15, 2016 at 16:40:49
Lew
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 Did you say Beveridge? I've got 2SWs in my basement as a second system. I absolutely love them. As you probably know, they're direct-driven by their own hybrid solid state input/tube output amplifiers that are built in to the base of each speaker. If you're using an external amplifier, you must have Model 3s or higher. Which ones?

About 40 years ago, I built a pair of transmission line woofer cabinets for KEF B139 woofers, an hommage to the IMF Monitor speaker that I loved in the 70s. (The woofer cabs were once part of a full-range system using also KEF B200 midrange and ESL tweeters, but they are long gone.) Over the years, I came close more than once to trashing the cabinets, because they were only taking up space. Then when I got the 2SWs, the KEF in TL cabs makes a perfect mate, from about 80Hz on down.

I probably listen to this system more than to my "upstairs" system, because it does not annoy my wife when she is trying to sleep, since the basement is two floors and two closed doors away from our bedroom.

 

Holy cow!!!, posted on February 15, 2016 at 16:44:23
Lew
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 I guess it was easy for you to know I was off base about the 12B4. That's a beautiful set-up, right down to the Audio Research SP3 or 3A or whatever iteration. That was the preamplifier, along with the AR Dual 50, that opened my eyes to tube amplification. OTLs came a few years later.

My friend and I used to joke that the safest way to use the Dual 50 was to keep it unplugged.

 

RE: Beveridge?, posted on February 15, 2016 at 17:10:11
AJ
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 Yes Beveridge,

I have the Model 3's. I am passively biamping right now with solid state on the woofers and believe it or not, a 18 wpc 211 SET Wyetech Labs Topaz on the line source.

I have replaced the woofers in the cabinets with Morel 10" and am using a pair of REL S2 subs as well.... It sounds pretty sweet.

Modjeski is building me a direct drive amp as we speak and I will going to the panels direct with about 2Kv and just subs- effectively a modern version of the very fine 2SW's that you have!

The 2SW's are a very special product. I know that when I'm done I will come close with a modern direct drive tube amp straight to the panels with no step up transformers.

There's nothing quite like the Beveridge experience ... especially directly driven like the 2SW and hopefully my incarnation. Modjeski has high praise for this modern direct drive design... we'll see.





 

RE: Beveridge?, posted on February 16, 2016 at 10:02:45
Lew
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 I have flirted with the idea of talking to Modjeski, and now you mention it, I don't remember what became of that conversation. I don't think he was willing to build a direct-drive amplifier de novo at that time. The OEM Beveridge amplifiers develop +/-1600v, or 3200V if you're a lumper. So, when you say 2kV, do you mean per phase or total from plus to minus?

I was lucky to find a guy on TubeDIY who also has 2SWs and is an EE. He walked me through trouble-shooting my amplifiers and from him I learned a lot about their care and feeding. I also learned the hard way that 1600V can jump a gap, into my finger tip from 3-4 inches away. The solid-state input and driver stages could probably be done better these days, but even he (my EE penpal) is loathe to do a re-design. Is Modjeski using all tubes now? Interestingly, inside each of my two amplifiers, you can see his signature in magic marker, dated 1979. Kind of like the Futterman H1 signed by JF.

I think what happened was I did not want to lose use of my speakers for the time it might have taken for RM to revamp the amplifiers. On the subject of bass response, the KEF B139 in TL does a great job of keeping up with the panels around the crossover point, but in my rather large finished basement, extreme low bass is not fully "there". I could indeed use a subwoof.

 

A question about your Model 3s, posted on February 16, 2016 at 12:37:44
Lew
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 Do you use them facing toward each other, as recommended, rather than at the listening position? Among Model 2 and 2SW owners there seems to be at least a few who prefer to aim the speaker at the listening position, rather than as recommended by Harold Beveridge. I am not one of those iconoclasts, but sometimes I feel like stereo separation is a bit too emphatic in the recommended orientation, and perhaps that is because I have my speakers a bit farther apart than is optimal for best soundstaging on all program sources. I did find that there is a limit beyond which the image fails to coalesce in the center, and it's different for different LPs. One can hardly be jumping up between records to wrestle with the distance between the speakers, so I leave mine as is. Otherwise, the front to back sense of depth is staggering.

 

RE: A question about your Model 3s, posted on February 16, 2016 at 13:31:43
AJ
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 We are hijacking this thread!

My placement is the classicly recommended positioning facing each other.

They are on the short wall about 16' apart. The length of the room is about 40'

If you PM I can send you something from Beveridge's Sales Manager regarding the proper placement of the speakers.

Thanks.

 

Fair point about "hijacking"..., posted on February 16, 2016 at 14:11:15
Lew
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 but I think the OP is happy. Anyway, I will PM.

EDIT. I just tried sending you an email from here. The notation says you do not accept emails. I do, so you could PM me.

 

RE: Fair point about "hijacking"..., posted on February 16, 2016 at 18:57:35
AJ
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Joined: February 24, 2001
 PM sent

 

RE: Beveridge?, posted on February 17, 2016 at 09:37:46
airheadair
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 Wow, this thread is truly amazing. AJ, can you post a bigger picture of the Futtermans?

Let me put in a word of praise for Roger Modjeski, who is now living in the Bay Area and helped me a lot with my own system: providing nice litter woofers and an excellent (Beveridge) crossover, retubing and adjusting my NYAL OTL3's (only one needed new tubes, he said), and then helping also with the somewhat defective used amp I had purchased on line for the woofers. My setup sounds amazing now. (But I'd love to hear the Beveridges at some point.) He has a very down-to-earth engineering approach, which is a breath of fresh air.


 

RE: Beveridge?, posted on February 17, 2016 at 10:09:37
AJ
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 Hi there,

I'm not sure if you are being serious LOL! .. if you look up at my first reply to the thread you'll see I posted a BIG pic of the amp and one up its skirt.

I've hand built a lot of amps and preamps but I just don't have the time any more nor the level of commitment to carry on a direct drive project to the end. So, Modjeski got the call after reading through his thoughts on Audio Circle some time ago. He makes a lot of sense to me as I have been trained in EE as well but just don't have the background experience he does in this speciality. I wasn't willing to spend the time to learn and experiment when he has done the work. I had been frustrated enough rebuilding quad esl panels in the past and while successful- it wasn't worth my time in the end.

I have tried Modjeski's crossover and subs for the Beveridge's but I did not like the imposition the crossover put on the transparency of the Beveridges. So , I went a different route with REL subs and like the results much more. The Beveridge's are incredibly revealing and it is crime to use anything but the best with them. I hear stories of some folks driving them with AV receivers after rescuing a pair... yikes.

If I go active again I have built my own crossover and it is , I believe, much more transparent.





Thanks.

 

RE: Beveridge?, posted on February 17, 2016 at 10:26:07
airheadair
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 Sorry, I didn't realize that your picture was your amp!

My Stax speakers are pretty revealing too, but maybe my ears aren't any more. Anyway i found that the midrange seemed better to me with the crossover in place than without it, perhaps because the bass was taken out of the amps/ESL.s

To clarify, what crossover are you using with the REL's?

Thanks.

 

RE: Beveridge?, posted on February 17, 2016 at 10:48:56
AJ
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 Hi,

The RELs tie to the outputs of the amp driving the Bev woofers and the RELS have their own internal crossover. It is REL "trademark" of how they hook up and the sub "sees" what the amp sees. This way, I don't have the linesources going through any active crossover. This keeps things clean.

The linesources are passively crossed over with the internal first order Beveridge crossover. I use a 150lb 211 SET amp on the line sources and I use a solid state amp on the Bev internal woofers , again passively crossed over internally. The SET obviously has some limitations but this is no ordinary SET it is a beast.

So, the system is bi-amped with the internal passive crossovers in the Bev.

The internal crossover caps and coils have been ridcuously upgraded at great expense.

It all seems to work and blend exceedingly well after alot of trial and level matching. I think the 2 subs helps even out room modes. Quite a few of my audio group have been suitably impressed on this contraption!

I used to use exclusively rebuilt Quad ESLs with all their limitations they continue to amaze.. the Beveridges sound bigger ( the Quads are small sounding) but the Quads play plenty loud for me and are really amazing if they are rebuilt.

I have the USA monitors as well - as good as they are- they are not ESLs or Beveridge's.

The Quads play really well with the Futterman- amazingly well.

 

RE: Beveridge?, posted on February 19, 2016 at 10:10:33
Lew
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 Sorry if this goes off-topic once again, but you probably know the answer to this question regarding the built-in woofer amplifier and electronic crossover circuits built onto the Bev 2SW amplifier chassis'. RM was kind enough to supply me with the amplifier schematics for a nominal fee, but I have never been able to obtain a full schematic that includes the crossover. I do understand that the built-in low pass filter part of the crossover is 18db/octave at 100Hz or thereabouts. But what is the slope of the high pass side of the crossover? On the amplifier schematic, a small value capacitor is shown to be in series with the input to the direct drive amplifier. If memory serves, the value is .022uF. This alone could constitute a passive first-order high pass filter in conjuction with the parallel resistance at the amplifier input, but is there upstream (active or passive) circuitry that adds to the slope of the hi-pass filter? My ohmmeter tells me that the upstream side of the .022uF capacitor is not directly connected to the RCA input jack, but beyond that I have never figured it out. Thanks for any info.

In practice, I use a restored Dahlquist electronic crossover for a low pass filter before the solid state amplifier that drives my Transmission Line woofers. I use whatever is built in to the Bev amp chassis for high pass, and I have always had the feeling I could do better, if I knew what was going on in that circuit.

 

RE: Beveridge?, posted on February 19, 2016 at 16:21:41
AJ
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 I have not looked at this schematic in a long time. I am by no means an expert.

It is part of the motional feedback system Beveridge used by injecting Rf and feeding back net diaphragm displacement rf signal to crowbar or limit excursion on the line source.

He was a pretty amazing engineer. Both he and Peter Walker could put a lot of the modern types to shame I would think!

 

RE: Beveridge?, posted on February 19, 2016 at 22:29:05
Lew
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 Although I responded to your PM slightly differently, on second thought, the function you are describing may be happening within the input and driver stages of the direct-drive amplifier proper, after the high pass filter, in other words. There's a 7.5M resistor that feeds back from the output stage to the driver stage, with ~1600V on one end and barely 3V on the end that is attached near the driver section. Lots of filtering going on in the input section as well. I don't pretend to understand it, but I have been able to work on it a bit only because of the tutelage of another EE Bev owner I encountered on TubeDIY. Like me, you can get the original Bev amp schematic from RM.

I quite agree, HB was at the very least a major innovator in the history of audio, if not a genius, and he gets very little credit for it, mostly because his company was so short-lived and the products are rarities. I do also think RM had a lot to do with the original dd amplifier. Every single aspect of the Model 2 or 2SW system is novel, yet the system as a whole is a smashing success. HB is easily up there with Peter Walker in my book.

 

RE: Beveridge?, posted on February 19, 2016 at 23:25:27
airheadair
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 Have you asked RM your question about the slope of the high pass filter? He should know.
I believe that the high and low pass filters on the external crossover he uses (mine is labeled Beverage RM 3 Universal Crossover) is 18 DB/octave on both sides. Roger told me he thought it important to get a lot of the bass out of the ESL panels as well as a lot of the midrange out of the woofers.

 

RE: Beveridge?, posted on February 20, 2016 at 12:00:48
Lew
Audiophile

Posts: 10911
Location: Bethesda, Maryland
Joined: December 11, 2000
 No, I have not asked RM the question. When I contacted his business in order to acquire a copy of the direct-drive amplifier schematic, I never got to talk to him directly. Once or twice I emailed him but never got an email response, either. However, his company was very prompt in providing me with the schematic, once I had sent payment.

In the pamphlet that Harold Beveridge concocted to go to purchasers of the 2SW, it does say that the low pass filter slope is 18db/octave. And I have always assumed that the high pass filter would have the same complementary slope, but that is not directly stated in the pamphlet. But I also have always wondered why there is that series capacitance in front of the amplifier input, which by itself would add a passive high pass filter with first-order kinetics. On the other hand, it does not seem to me that 6db/octave would be sufficient to sufficiently attenuate the demands upon the panels in the 2SW to produce bass response. So it is most likely a net 18db/octave slope with the gain maintained by an active element in the crossover.

 

RE: Harvard Electronics = Futterman, posted on February 25, 2016 at 12:37:29
Awe-d-o-file
Dealer

Posts: 21037
Location: 50 miles west of DC
Joined: January 10, 2004
 You can put all pics in one post. After you choose the file hit preview instead of post and keep adding photos.

ET
ET

"If at first you don't succeed, keep on sucking till you do suck seed" - Curly Howard 1936

 

RE: Thanks for the correction,.., posted on February 26, 2016 at 11:18:33
6bq5
Audiophile

Posts: 4387
Location: SF Bay
Joined: August 16, 2001
 which beveridges?
Happy Listening

 

RE: Thanks for the correction,.., posted on February 27, 2016 at 01:54:26
AJ
Audiophile

Posts: 532
Joined: February 24, 2001
 I have the Model 3's- thanks

 

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