DavidDru Posted March 13, 2015 Author Report Share Posted March 13, 2015 Citation? Hell yeah. Go check out Jim McShanes web site.http://www.mcshanedesign.net/ Link to comment Share on other sites More sharing options...
owlsplace Posted March 13, 2015 Report Share Posted March 13, 2015 Smart man.I purchased an Adcom GFP565 preamp today from an AK'r on Bartertown to pair with the 5500. Man, good preamps are expensive so I am going to have to work my way up the ladder over time on them. Thought the 565 was a good starting point as it was rated as one of if not their best and one of the best under $1000 by Stereophile magazine when it came out. Alegedely has a very good phono pre section.Almost pulled the trigger on the SLC505 that was recommended earlier for a passive preamp but decided not to at the last minute and it went for $115 plus shipping. The 565 can be used in bypass anyway.Sounds like a good place to start. I've been thinking a tube preamp for some reason. Not sure I'll ever get to it though Roger,My copy of the "fusing" instructions is kind of lo-rez but it looks like they recommend FNM-8/10 for the AR-3 and AR-5. Did a Google search and those suckers are expensive ($13.33 each at Mouser). Is that what you're using?You inspired me to rummage through my parts box and I actually found a pair of FNM-8/10 fuses and BUSS 4421 fuse blocks. Also have a pair of FNM 1 1/4 fuses, which is what they recommended for the AR-3a. My speakers are sort of "Franken-3a's" so maybe I'll go with the 1 1/4 size. . . . when I get a round tuit KentCheck the auction site <$2ea. There seems to be a decent supply coming out of the woodwork these days -- Zoro for $7ish.RogerIs it a no-no to use electronic Speaker Protection rather than fuses? Here is one in kit form but I feel sure you can buy some made up if you do not want all the soldering involved.http://www.farnell.com/datasheets/1581785.pdfI looked at the Velleman speaker protection kit and didn't think the relays were up to the challenge of the Adcom amp. There is a design for a circuit on the web (AK?) that you can build using heavier relays which are expensive. At any rate, having the speakers fused means they are protected if you start swapping amps around. The Russound speaker switch I'm using has built in protection but I'm not sure what's in the box and haven't gotten curious enough to open it yet. It only works when the impedance matching function is switched in which appears to be some kind of resistive bridge circuit.Roger Link to comment Share on other sites More sharing options...
stupidhead Posted March 13, 2015 Report Share Posted March 13, 2015 By the way, here is a pic. Link to comment Share on other sites More sharing options...
owlsplace Posted March 13, 2015 Report Share Posted March 13, 2015 Very nice, that HK tube amp, wonder how many are out there? Don't need speaker fusing with that one.Roger Link to comment Share on other sites More sharing options...
DavidDru Posted March 13, 2015 Author Report Share Posted March 13, 2015 looks in great shape. The 12by7a's across the front look like nice old stock tubes. What are the KT88's? Like my ST70 that Citation has the 4ohm terminals just awaiting AR3's but at 60w/ch. Link to comment Share on other sites More sharing options...
stupidhead Posted March 13, 2015 Report Share Posted March 13, 2015 David, I am not qualified or knowledgeable enough to answer your questions. All I know is that this piece looks like a contender, and I can likely get it for a reasonable price! This would obviously be a major purchase (at least for me) and the bottom line is would it be a good choice for the 3s, or would something else of similar caliber be a better choice. Link to comment Share on other sites More sharing options...
VintageMan Posted March 13, 2015 Report Share Posted March 13, 2015 Very nice, that HK tube amp, wonder how many are out there? Don't need speaker fusing with that one.RogerWhen would you use the FNM-8/10 fuse with the AR's? Link to comment Share on other sites More sharing options...
DavidDru Posted March 13, 2015 Author Report Share Posted March 13, 2015 David, I am not qualified or knowledgeable enough to answer your questions. All I know is that this piece looks like a contender, and I can likely get it for a reasonable price! This would obviously be a major purchase (at least for me) and the bottom line is would it be a good choice for the 3s, or would something else of similar caliber be a better choice.Thats a great question. i think it could be posed over on the tube section of AK and you will get plenty of responses. I will ask it of a few who might know as well. I wouldn't doubt if someone on here has a feel as well for you. You would be stepping into another arena though and it will require investment.Those Citations are pricy but special. You will probably want to factor in a comparable tube preamp though, (a Citation I of course would be ideal) which might make the cost even a bit more of a challenge. I am not overly versed on the tech aspects of all of this stuff, but I will say it is kinda nice to have both higher powered solid state as well as the tube gear for various uses. Link to comment Share on other sites More sharing options...
JKent Posted March 13, 2015 Report Share Posted March 13, 2015 When would you use the FNM-8/10 fuse with the AR's? Link to comment Share on other sites More sharing options...
VintageMan Posted March 14, 2015 Report Share Posted March 14, 2015 Thanks for the documents.I've found the 2 types of fuses online, but which fuse-holders do I use?I see a lot of different types on eBay. Link to comment Share on other sites More sharing options...
JKent Posted March 14, 2015 Report Share Posted March 14, 2015 I don't know what's available in Europe. The FNM fuses are 1-1/2" x 13/32" or 38.1mm x 10.3mm. I think these are called "midget" fuses. Here's the data sheet http://www.farnell.com/datasheets/658457.pdfSingle pole Bussmann fuse blocks 1104 are the right size. http://www.cooperindustries.com/content/dam/public/bussmann/Electrical/Resources/product-datasheets-a/Bus_Ele_DS_1104_BM_Series.pdfI have the old Buss #4421 single fuse holders.-Kent Link to comment Share on other sites More sharing options...
VintageMan Posted March 14, 2015 Report Share Posted March 14, 2015 I don't know what's available in Europe. The FNM fuses are 1-1/2" x 13/32" or 38.1mm x 10.3mm. I think these are called "midget" fuses. Here's the data sheet http://www.farnell.com/datasheets/658457.pdfSingle pole Bussmann fuse blocks 1104 are the right size. http://www.cooperindustries.com/content/dam/public/bussmann/Electrical/Resources/product-datasheets-a/Bus_Ele_DS_1104_BM_Series.pdfI have the old Buss #4421 single fuse holders.-KentLooks like I need the Bussmann BM6031SQ of BM6031PQ. Link to comment Share on other sites More sharing options...
VintageMan Posted March 16, 2015 Report Share Posted March 16, 2015 Looks like I need the Bussmann BM6031SQ of BM6031PQ.Could anyone shine his light on this?And do I buy the FNM8/10 125Volt or 250Volt?Found the answer on that last on myself Link to comment Share on other sites More sharing options...
owlsplace Posted March 16, 2015 Report Share Posted March 16, 2015 David, I am not qualified or knowledgeable enough to answer your questions. All I know is that this piece looks like a contender, and I can likely get it for a reasonable price! This would obviously be a major purchase (at least for me) and the bottom line is would it be a good choice for the 3s, or would something else of similar caliber be a better choice.May want to ask John (xmas111) over in Plymouth, MA. This is his set up with a pair of LST's off camera:Roger Link to comment Share on other sites More sharing options...
stupidhead Posted March 16, 2015 Report Share Posted March 16, 2015 That's a beauty Roger. And David here is the response from the seller when asked about specifics. "The only thing that has been upgraded on this unit,that I know of, is in the power input section of the amp. My tech is getting me a list of the components that were used. I will add he is real good and real slow. There are no modifications or circuit changes on this amp. The amp comes with 4 new matched JJ Tesla 6550. I am offering 4 RCA 6550 matched tube for another $100. In my test of these, two are real strong and two are real good." I am totally in the dark here. Link to comment Share on other sites More sharing options...
DavidDru Posted March 16, 2015 Author Report Share Posted March 16, 2015 Well, The Citation II is one of the Holy Grail level vintage tube amplifiers and if you want to go vintage, it would be a great piece. As with any of these things that are from around 1960, it all depends on how much use it got through the years, how it was stored, and how ready it might be for a rebuild. The fact that the Power Supply has already been done is a great start, as long as it was done well. That alone can be a costly fix/upgrade and is where all restorations on these look to start sp teh old components dont fail and cause additional harm. I am sure your tech will have plenty to report on this as well as what other aspects he might think you might be getting yourself into. Bad transformers is a bad thing. Many of the other components are readily available or can be upgraded/modded. In working condition these typically go for $1,000 and on up depending on how much re-building has been done. In non-working condition, they still go for that much it seems. If you are getting it for a good price, you could always go for it and then sell it off if you feel like you don't want to get into high level and high cost modifications later.For sure check out jim McShanes web site. http://www.mcshanedesign.net/ He is the HK Citation guru. Also, do a Citation II search in the tube section of Audio Karma and read thru the various posts about them to see what folks have done. I am fairly new to tubes myself but I found working on my ST70 to be pretty easy and new parts not overly expensive. Same with my tube preamp. i just replaced the volume control and have a new power supply awaiting for my preamp (one thing at a time). But, the possible upgrade and modification options are endless and you have to be careful about how far you want to go. Some of the stuff just needs to replaced that has aged out including things like selenium rectifiers, old caps, etc. As far as tubes go, when these old amps come with tested as working old tubes, the value increases. An old tube might cost $165 and a new version $35. Many feel the old are superior and covet them as of course they are dwindling in supply. Some may say it is not worth the extra $. You can see the difference between the old and new on some of the tube stores web sites. I thought the Citation II used the KT88 tube and not the 6550. Something to ask the tech and owner about I guess. I believe the Citation allows you to set bias on each socket/tube separately so the tube values are not as difficult to deal with, but it is great to have matching. On my ST70 I can only set bias in pairs so I had to have 2 pairs of matching tubes. When one $200 tube went out, the other was no longer useful unless I happen to find a match. Would be a great amp when in service. The question remains is it ready for service and how much are you willing to pay. I can not speak for you, but I will say this. If it is in working condition, the tech is comfortable with it and it can be had for less than $1,000, I personally probably wouldn't hesitate. Also remember though, you will need a nice pre to go with it. You will probably find yourself looking for the Citation I preamp sooner than later. I think a big difference between tube amps and the newer solid state stuff is that with tube amps you can find yourself fiddling around with it over time. The newer solid state stuff is pretty much plug and play.And yes, PM xmas111 to see if he can chime in on how the pairing of the 3's and the Citation works for him. Link to comment Share on other sites More sharing options...
JKent Posted March 16, 2015 Report Share Posted March 16, 2015 So inspired by this thread and John's (XMas111) dongle pictured in Post #14 here http://www.classicspeakerpages.net/IP.Board/index.php?showtopic=8255I decided to pull out the fuses, blocks and inline banana jacks that I bought but just left in my parts box (a lot of good they do there) and cobble together some fuses for my Ar-3s.Jacks are Pomona 6384-02. They come in pairs and are sold by Mouser, Digikey and others.-Kent Link to comment Share on other sites More sharing options...
ra.ra Posted March 17, 2015 Report Share Posted March 17, 2015 Very nice and simple, Kent. Snip, strip, solder + one screw. I recall that you like to use the double banana plugs, so splicing in a fuse on the dongle is a great idea.I seem to recall a recent thread here about a Heathkit amp, so I just wanted to mention that xmas111 is also very knowledgeable about Heathkit, tho' maybe most of his impressive collection might be receivers, not amps. Link to comment Share on other sites More sharing options...
owlsplace Posted March 17, 2015 Report Share Posted March 17, 2015 So inspired by this thread and John's (XMas111) dongle pictured in Post #14 here http://www.classicspeakerpages.net/IP.Board/index.php?showtopic=8255I decided to pull out the fuses, blocks and inline banana jacks that I bought but just left in my parts box (a lot of good they do there) and cobble together some fuses for my Ar-3s.Jacks are Pomona 6384-02. They come in pairs and are sold by Mouser, Digikey and others.-KentMy fuses came in today. Guess I got carried away with the fuse blocks -- Buss 6031SQ, 30A, 600V, double spade lug or screw terminal! Looks like you need a crowbar to pry the fuse out Not sure if I want to do jacks till I get my room set up properly. Using rings at the moment.Roger Link to comment Share on other sites More sharing options...
ar_pro Posted March 17, 2015 Report Share Posted March 17, 2015 Be careful, you tube mavens - those filter capacitors can hold a lethal charge!This site lists a number of safety tips:http://www.aikenamps.com/index.php/safety-tips-for-working-on-tube-amplifiers Link to comment Share on other sites More sharing options...
DavidDru Posted March 17, 2015 Author Report Share Posted March 17, 2015 Geoff,Here is another inspiring photo for ya! Link to comment Share on other sites More sharing options...
VintageMan Posted March 17, 2015 Report Share Posted March 17, 2015 Geoff,Here is another inspiring photo for ya!Nice!What that blue-lighted amp next to it?A Sansui? Link to comment Share on other sites More sharing options...
DavidDru Posted March 17, 2015 Author Report Share Posted March 17, 2015 Nice!What that blue-lighted amp next to it?A Sansui?McIntosh Link to comment Share on other sites More sharing options...
JKent Posted March 18, 2015 Report Share Posted March 18, 2015 Be careful, you tube mavens - those filter capacitors can hold a lethal charge!This site lists a number of safety tips:http://www.aikenamps.com/index.php/safety-tips-for-working-on-tube-amplifiersDefinitely good advice there. Much of it also applies to solid state gear. Using a resistor to discharge big caps is one I knew about but sometimes forget to do. And I have all the parts for a dim bulb tester but never got around to assembling it. Dumb. Now that I finally got around to making the fuse pigtails for the speakers maybe I'll build the dim bulb tester. May as well also put together an insulated resistor for shorting caps..........Kent Link to comment Share on other sites More sharing options...
DavidDru Posted March 18, 2015 Author Report Share Posted March 18, 2015 Definitely good advice there. Much of it also applies to solid state gear. Using a resistor to discharge big caps is one I knew about but sometimes forget to do. And I have all the parts for a dim bulb tester but never got around to assembling it. Dumb. Now that I finally got around to making the fuse pigtails for the speakers maybe I'll build the dim bulb tester. May as well also put together an insulated resistor for shorting caps..........KentYeah, the dim bulb tester is an easy thing to put together and a really handy piece of mind, especially with tube stuff. I run a variac in line with it for powering up anything old and particularly of tubes to make sure I don't do more harm. Of course you just don't know if someone has already tried to power up something before you got to it, especially at the thrifts. Odds are they have.Was watching an Ebay listing for an Adcom GFA555, GFP555II,GFT555 that ended today. Went for $470 total. Pretty good deal. Link to comment Share on other sites More sharing options...
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