Deang

Sounds to me this has already been asked at the other forum and resolved. Let's review. "Okay I need some serious clarity on all the different phase splitter tubes and which is the best to use in these amps? Is there a Sonic difference ? I now have 3 different Amps and they all spec for a different tube. 222C specs 6U8 , 299A specs 6BL8 and now LK-72 specs 6GH8. So are all these tubes interchangeable ?? Which tube is the best for the job ?? I know that everyone likes the Jan 6U8's that are available and really cheap these day's. But is it the best choice or more vintage offering's a better way to go??" The question is clear enough to me, and so are the answers. "It is quite simple, Craig. The 6U8 and the 6GH8 tubes are identical in design and purpose to each other. On the other hand the 6BL8 tubes are different, they are a lighter duty (lower voltage ratings) tube and can be replaced by the 6U8/6GH8 tube (which is a far better tube for your set. The 6BL8 tubes and the 6U8/6GH8 tubes all have the same pin out). You can't replace a 6U8 with a 6BL8 tube, but you can replace a 6BL8 tube with a 6U8/6GH8 tube. This is the only way it can work. Personally, I do think that the JAN Philips 6U8A tubes work really nice. For the buck, buy these....really quiet!!!" The differences are quite notable, but the 6U8 has much higher voltage ratings at the plates and the screen of the triode. This tube can be used as a substitute for the 6BL8. The 6BL8 can NOT be used to be as a plug-in substitute for the 6U8 without mods to your set. Use a 6U8 tube. It is a one-way street here... Yet you say to Craig, "Not once did anyone mention substituting the 6U8 tube for the 6BL8 tube in a 299." Gee, you're right...not once, but three or four times. It is apparent this situation is similiar to the 6DJ8 and 6922/7308. You can use the 6922 or 7308 in place of the 6DJ8, but you can't use the 6DJ8 when the 6922 is specified. At this point -- the score is Nosvalves 2, "Expert" Zero.

No, no, no. My Sony 9000es Combination player (DVD, SACD, & Redbook CD) crushed my old Anthem CD-1 in week long comparisons. The Anthem was about 5 years old, used the very fine Dual Burr-Brown PCM 1702P 20 bit DAC, and had a tubed output. I paid $1800 for the Anthem, and $1000 for the Sony. I attribute the primary difference to the newer DAC's and very hefty power supplies in the Sony. Things have come a long way over the last 3 to 5 years. Save your money and get the Rega, or a newer Sony -- like the 222ES or 775.

Well yeah -- you got to do the RS-7's for the proper setup. As much as I love the RB-5's, if I was going multichannel it would be the RS-7's.

Out of the box, the RF-7's are stiff, constricted, and somewhat hard sounding. Wait a couple of weeks, at which point they will bowl you over with sweet perfection.

The poor RF-7. It just can't win. When someone with great hearing listens to them -- they're too bright, and when someone half deaf listens to them -- they're too dark. But when they are heard by those of us with 'average' hearing...ah yes.

I beg, borrow, and steal data -- and then I regurgitate it. I read a lot. A lot. I implement things based on what I read -- and try really hard to be objective. It's time consuming and exhausting, but it's the only way to sort out the what's true from what's voodoo B.S. There is also a handful of people that hang out here that are freaking wizards. We got Leok who can shrink my skull down to the size of a golf ball with the math, Mdeneen - who's probably slung enough solder to hold an aircraft carrier together, and Mobile_Homeless - who can hear the electrons shaking down the wire in a resistor. We got a few others as well, like Mike82, Mallet, and Artto - who also have a wealth of experience. Behind the magic there is the math, and in between - our ears. People like Craig and myself are just benefactors, and pass along the good stuff we've learned to others. Thanks for the compliment though, but in truth - I really only understand the surface stuff. In this hobby though, even the surface stuff can drown you.

I'm not surprised one bit. Both the RC-7's I originally bought and used as monitors, as well as the RF-7's -- were very grainy and hard out of the box. It takes at least two weeks of constant listening before they relax and open up. What a shame you weren't more patient. Also, the RF-7 does not possess a benign impedence curve. It is possible that with your SET amp -- it may have been tracking the impedance curve. You probably weren't getting anything near flat response. Room acoustics may have exasperated this as well. Fixes for this -- but you visited us too late.

Don't get me wrong -- $5000 cables are ludicrous. Hell, I think anything over a few hundred is ludicrous, and these prices reserved for solid state, and speakers that need 200 wpc just to get the drivers to move. The nice thing about horns and tubes is you really don't have to go broke on good cables -- but there is nothing wrong with spending $100 on a set of speakers cables if they help things gel better. The Goertz comes in right about at that amount. For some reason, I found both the Cornwalls and the RF-7's to sound smoother and more relaxed with either very tightly twisted stranded 14 or 16 gauge, flat braided, or solid core. Believe it or not, I actually preferred the Radio Shack 14 gauge Megacable over the Tributaries stranded 12 gauge I compared it to (basically the same as standard Monster 12 gauge). A case where the cheaper cable won out. No jaw dropping differences here, but differences none-the-less -- that over the course of a few days made themselves readily apparent by using a couple CD's that I knew backwards and forwards (from my old spinning the turntable backwards days). The Goertz cable OTOH -- though not jaw dropping either, had me shaking my head. Good stuff. Excellent for horns, old and new alike. Now, Randy Bey didn't like them, and Kelly REALLY likes the Risch Cross Connect. So -- personal preference comes into play here. The main thing to remember is that though the cable is the interface between amp and speaker -- other things come into play that will change perception as well (room acoustics, source, etc, ...). No, you are not losing fidelity with the Monsters -- but they may not be bringing something out that another cable might -- something you might prefer over what the Monsters are giving you. With that HT receiver...The Risch Cross Connect, or the Cardas Twinlinks might be the better choices. http://forums.klipsch.com/idealbb/view.asp?topicID=31061&pageNo=1&num=&sessionID={A4D917FD-5502-47B2-A928-BC69445BCDD7} http://forums.klipsch.com/idealbb/view.asp?topicID=29914&forumID=68&catID=19&search=1&searchstring=&sessionID={D76CF918-ED00-488A-AD44-8B2B339C890F} http://forums.klipsch.com/idealbb/view.asp?topicID=29704&forumID=68&catID=19&search=1&searchstring=&sessionID={D76CF918-ED00-488A-AD44-8B2B339C890F} http://forums.klipsch.com/idealbb/view.asp?topicID=29924&forumID=68&catID=19&search=1&searchstring=&sessionID={D76CF918-ED00-488A-AD44-8B2B339C890F}

An Eico ST-70 is rare find indeed!!

You are not likely to hear much difference in cabling until you have a system with enough resolving power to allow you to hear the effects various cable types have on the sonic signature. I don't mean this as an offense -- it's just the way it is. I like the Monster 550i interconnects. A very good cable for the money, and as good as most will ever need. My personal favorite at the moment, in my RF-7 based system -- is the Cardas 300B. Speaker cable wise, it's hard to go wrong with the Goertz cable. m00n is about to learn his cable lesson when he gets his Belles and tube amp. Stevie, why don't you tell us something about your budget constraints, room, and listening habits. It's important stuff to know before anyone can give you an amp recommendation.

Go for it. All of these people are professionals -- and they are insured. Couldn't possibly be any worse than UPS dropping kicking things back and forth across the country. Mostly just forklifts and trucks -- if anyone is likely to screw up -- it will be you trying to get them off of your truck and set up in your house.

Beyond cool.

We need to hook up John. I really want to hear your Klipschorns, and I'd love to get you over here to let me plaster you with my RF-7's. Where are you at with the Scott right now?

I picked up some new stuff here lately, and thought I'd post some thoughts. I like the cookie cutter grunge bands. I dig the grinding guitars, buzzing of the Marshall and Fender amps, wicked slamming drums, and men that actually sing like men. New Godsmack -- same 'ole same 'ole. Disappointing. 2nd CD is the best -- it's all you need of this band. Queens of the Stone Age -- interesting CD. I actually like most of it, and it's one of those that has that "grow on you" quality. The mix sounds like it was done on an old Teac 4 track. Different. The name of the band was derived as a joke played on their fans -- which they knew in advance would be "homophobic rednecks". Cinder -- wanted it, but not out yet. Sure to be major kick butt stuff. Looking forward to this one. East West -- debut CD -- a must have. Feezal -- debut CD -- a must have. Chevelle -- debut CD -- a must have. Rush, Vapor Trails -- a must have. None of the above for the faint of heart, and may need more than a watt or two, to get the most out of them. ;~) Enjoy!

Craig -- I was just razzing you. 30 wpc is perfect for the big stuff. Wiring those pentodes in triode probably does help smooth things out a bit with those earbleeders. Something I haven't figured out yet is what happens to the distortion levels with this mod -- can you see it on a scope? Tom, "I have a Eico HF-81 driving them. It's only making about 10 watts/channel..." I thought these were 14 wpc -- or screw up your pentodes too? "With one (1) watt your Belles will make over 100dB of sound...what you need is an amp that's optimized to put out super clean power in 1-5 watt range." Here we go again. Am I talking into the wind here? Why not just run a Decware Zen? 1.5 watts of Single Ended Triode -- for peanuts no less. Run up to that watt, get your 101db -- and it will sound like Sh!t. "I measured the voltage at the speaker terminals, it was running in the 100 to 300 millivolt range. One watt is about 2.8 volts. My speakers were generating 90dB with about 1/15th of a watt..." Betcha those meters aren't telling you the whole story. Bruce Edgar used to sing this tune too, however as of late -- has been advocating the idea that big 'ole horns need at least 30 to 40 watts. "A 50 watt amp is going to be in it's sweet spot at 35 to 45 watts..." I agree 50 watts is complete overkill for Belles, but I don't understand what you are saying here with this statement. Would you mind elaborating for me? I'm being sincere -- I just don't understand the statement. "What you need is an amp that puts out super clean low distortion power at 1 to 5 watts." Are you saying that a 50 watt amp is incapable of doing this? How about a 20 watt amp? This is such a generalized statement -- it almost doesn't mean anything. How do we define "super clean", and what's cleaner -- a push-pull running pentodes at a watt in Class A, or a pentode wired for triode at a 1/4 watt in Class A? Bottom line is that you are right for the most part, and what I would really like to see Moon do -- is get himself 20 good watts of vintage, let Craig work it over -- and get into the music.

I don't think Mark would sell them to you if he knew you were going to take them out of Ultra-Linear.

butthead. Unfettered, crystalline, fully reproduced without distortion. Sounded pretty good. Auditions for Rock bands start next week.

The system as a whole takes on the sonic character of the solid state preamp. Colder, harder, sterile. However, put a tube preamp in front of a solid state amp -- and the system takes on warmth and smoothness.

Again, Mark reading into, and fine tuning my thoughts. Yes, I am thinking of dynamic peak capability. This is what I meant by "headroom". The music goeth where it willeth -- and I want my freaking amp to follow it all the way to the top. I want that intense peak, which only happens in a millisecond -- captured and reproduced -- not clipped off. Hi Pete, Neat article. Mark pretty much covered my thoughts on the issue, so no need to repeat it again. I did point out that Heritage is a different animal, and that low power would work great. Heck, Kelly runs Cornwalls with the Moondogs and loves it, Leo seems happy enough with them as well, pushing his RF-7's, and I was actually very pleased with the Apollos for the most part. The problem came in when I wanted to go to 95db, and all the quick, good stuff above that -- was being pinched off. How can anyone NOT hear this phenomena. Give me 10 seconds with a Metallica or Rush CD, and your volume control knob, and I'll have you in the fetal position -- and it WON'T be because I went higher than a half watt on your Klipschorns. It'll be because of the distortion related artifacts, and your 15 incher wobbling all over the place from the almost non-existent damping factor of SET. I say 101db with one watt on a 15 watt amp sounds better than 101db with one watt on a three watt amp. One comes with pain -- the other does not. "How loud can you listen to in a home environment?" I like 90-95db many times. However, this area now sounds cleaner, smoother, tighter, and more dynamic, with the Quicksilvers than it did with the Apollos. "Paul Klipsch demonstated his K-horns in a auditorium filled with people using a whopping 5 loud watts." With all due respect, it would have sounded better with 15 to 30 watts. "...The bandwidth will not suffer if quality components (OPTs, caps, etc.) are used and as long as the integrity of the build is the epitome of craftsmanship." Agreed, but this comes at a price, and often a hefty one. Not everyone can afford this. I say the quickest way to high performance with tubes, and at a level most can afford -- is moderately powered pentode push-pulls, or Beam or Pentode tubes running in Ultra-linear. And I'm here to tell you, if one listens to Rock-n-Roll or Pop music, the differences in actual sound and imaging between all of these different amps -- is anything but jaw dropping, and amounts to nothing more than a very small hill of beans -- and a bunch of hair splitting. Personally, I say one does themself more good by cleaning up a crossover -- and not cheating on the preamp. "As far as dynamics go, I've used various amplifiers (SS, tube - all types) & the dynamics of my current set-up is unsurpassed." It's all in your head. Just kidding. I believe you. There are certainly aspects of the Apollos I miss. I don't think it's in the area of dynamics though -- I think it's more in the area of microdynamics, or the overall resolving power of minute details. I feel very strongly the Quicksilvers give me most of this, without the limitations I experienced with high SPL's. Again however, we are not talking K-horns, Belles, or LaScala's here on my end. I simply HAVE to concede this point to a degree. OTOH, please don't discount my musical preferences. I'm positive I could make you rethink your position somewhat under the right circumstances. "I may add that the quality of pre-amp & of course, component system synergy is VIP." We are in total agreement here. The best thing Kelly ever did for me was getting me to rethink the preamp thing. Mark was instrumental here as well. Yeah -- got to have a killer preamp. Dare I say it might do more related to what we actually hear than the amp? Put a solid state preamp in front of a great tube amp -- what happens? SPL charts: Why do they always leave screaming wives off of these things (another reason why I need 60 watts). I had the meter out the other night, and Temple, my two year old -- thought is was like a microphone she could sing into. She noticed what was going on, and leaned into it making sounds. Now Temple is quite a card, and it didn't take her long to figure out how to peg the meter. Just to mess with her head, I moved the dial to the 110 setting. She noticed the needle stopped moving, and immediately responded by raising her voice. I made the mistake of telling her she would have to scream to see it move. Now -- we are talking the little girl "scream". You know the one. She let one out that sent the needle all the way over -- 116db. Did it hurt my ears? No. Anyone want to take a shot at guessing why not?

Yep, Yoda likes the 6SN7's in the line stage. Leo likes them as well. I'm running Edmond's (Jazzman's) Cary SLP-90, which is really a SLP-94 (I still haven't figured this one out yet), and uses four 12AU7's for the line stage and two EZ81's as rectifiers. It's difficult to evaluate as compared to the AE-3 DJH (used 6SN7's) I just sold, since I made the amp change at the same time -- but the system as a whole sounds dynamite. Remember, it's just not the tube type, but the ciruit as a whole. Also, some of these nicer Cary's remove the transformer from the main unit into a separate chassis -- which surely lowers the noise floor. Evidently, this is the case as well with the SLP-74. Getting the power transformer AWAY from the main chassis should not be trivialized -- noisy bastards that they are.

Tuner should be secondary to good sound overall. At $600, $400 is left for a good used CD player.

Somehow, Craig went from 'NOSvalves' to 'NOSvalues'. SLP-74: Looks like a more affordable version of the SLP-94 variety - as both are Class A triode, and use the 12AU7. The SLP-74 uses an epoxy circuit board instead of point-to-point wiring, and is solid state rectified versus the tube rectification used in the higher end Cary stuff. While my ears don't seem to have a problem with solid state rectification in amplifiers, I think it's important to get it in a preamp -- as it does add warmth. I tend to think point-to-point wiring is important as well, but for the life of me can't tell you why -- I think it's just 'mental'. However, a Cary is a Cary, and it's hard to imagine it not sounding great. How much is the asking price?

"...what makes one tube amp better than the other". The total package. The ciruit type, tube type, or parts used -- alone -- don't tell the whole story. It's the engineering skill of the designer who actually knows what the hell he/she is doing, and to bring everything to the table -- including their ears. So Craig, tell me -- what would you rather have? A set of Dynaco MK III's running in ultra-linear with a little bit of feedback, or a Eico, Scott, Fisher, or SET? Don't you even try to lie to me or cough up some total B.S.

I like tone controls. With Heritage -- they are nice to have.

The Sonic Frontiers 'Taste of Tubes' book is great. Here's some other stuff. http://ken-gilbert.com/techstuff/vtf.html http://www.turneraudio.com.au/htmlwebpgs02/designphilosophy.htm http://www.pentalaboratories.com/audio_help6.asp Bottom line: It's not any one thing in an amp that makes it sound good -- it really has more to do with the designers knowledge base and skill-set -- and their ability to balance everything out for the "best" sound. GENERALLY speaking: SET amps, or directly heated triodes (and pure Class A) will give you the highest level of transparency, but at the expense of some bandwidth and headroom. However, they offer the most forgiving form of clipping. They are great amps for high sensitivity speakers like the Belle -- as long you don't plan to drive them hard. After that -- it's push-pull, with more flavors than Baskin Robbins. A push-pull amp CAN use directly heated triodes like the 2A3, but like SET, can get expensive. The only affordable one I can think of is the "Joplin" kit from www.diycable.com . Along with the push-pull bit, you have the various tube types, whether beam tubes like the KT-88, KT-66, KT-90, etc, or pentode types like the EL-34 and EL-84. To make matters more confusing, you can also wire a pentode tube to run as if it's a triode tube -- or make a 'new' tube by running any of the tubes above in ultra-linear. Lastly, there is the 'Class' of the amp - A, B, C, D, T, AB1 AB2, and AB. I like everything I've heard so far -- and it's best not to compare so much, but to take each one on it's own merit. What's 'best' is simply what brings a smile to your face. If I had Belles or Klipschorns, and was on a limited budget -- I would buy a Scott 299B, and some nice NOS tubes. The Scott is a straight up push-pull amp using the EL-84 pentode. Ain't nothing wrong with that. I worry a lot about the headroom factor. Many here, most of whom I respect quite a bit -- will say you just don't need more than a few watts for the big Heritage stuff. Maybe true most of the time -- but some good Rock music can suck the power out of these amps right quick. I'm sorry, but clipping is clipping no matter how graceful -- and I want my amp to get it done. I think the big stuff should be run with at least 15 watts if you plan on having a headbanging session from time to time. Trust me, once you hear those horn loaded 15 inchers -- you're going to want some good control. You know, if it's really just about the first watt -- we would all be using Zen's. But what happens with the Zen? Well, there's nothing beyond that first watt. Those here who have tried them -- sent them back. Don't tell me it's just about the first watt. So now, some of you have 3.5 watts -- and you're still saying it's about the first watt! No -- it's about sufficient headroom. It's always about that -- and always will be. Listening tastes and preferences will dictate how much headroom one needs. I'm running the Quicksilver M-60's right now. 60 watts of EL-34 push-pull in ultra-linear, Class AB, with 12 db of negative feedback. I was upstairs with my son last night working on his Pinewood Derby car. I've spent the last week really getting serious about speaker placement and room acoustics, but have been too busy to really sit down and try some things. I had David Gilmour's first solo effort going on the 9000es, and I really don't have any idea what got into me -- but decided just to walk over and turn the Cary's volume control over some. I'll just say I have no problem trading a miniscule amount of transpareny for what I experienced last night. Was I using the whole 60 watts? No. But I sure as hell wasn't going into clipping either. The advantage of this particular design is that with my RF-7's, 99% of the time, I'm never out of Class A -- and when I go into that other 1% -- I'm never going into clipping -- ever. I have teeth rattling bass and a treble that's glass smooth. Of couse, this is with my RF-7's, which have completely different crossovers than stock. Heritage is not Reference however. Those big horns don't need 60 watts by any stretch of the imagination. I do think they need more than four though. Four watts of Class A SET is probably great, but I would only recommend very low power if you are primarily going to use these for late night vegging sessions, or occasional jamming around 90db. If you plan on doing ANY intense listening -- bump the power up. The more power you have, the more CLEAN power you have. Also, the more power you have, the longer the amp will stay in Class A at those low to moderate listening levels. Something like the Scott gives you a solid watt of Class A. It's enough.