@decooney Hi , thanks for the advise. I have no idea how much time they ran after the repair. They installed new resistors, Hexfred diodes, new caps in addition to MORE caps. You can see massive pairs strapped to the chassis on the inside edge. Plus all new tubes. It’s been on low for about 14 hours. Wife just left so I turned it up, still harsh but I can tell an improvement. The upgrade tubes include 2 JJ gold pin 12AU7’s and a new production Tung Sol 12AX7 in each amp. Pardon my language but JJ’s sound like shit. I have a quad of Nickel Seimens and a quad of Tekefunken G73-R’s to try. I’m going to call Brent Jesse and get a pair of quality Tekefunken 12AX7’s this week. I have zero 12AX7’s to try. I wish there was a tube library so I could try some stuff. But at $3-500 a pair for good 12AX7’s I’m kinda screwed. The other issue is my wife took all my play money for her kitchen remodel project. I still need big boy speakers. But this is a First World problem and I’m a lucky guy. So after the amps get a week or so, I’ll change all the small tubes. If these Psvanes don’t improve in the bottom end I’ll try my Schiit Loki, but I’ll probably get an octet of KT 120’s. Having been warned by Rogue every time I mentioned new tubes, I’ll probably buy an octet from Upscale.
Looking for advise regarding Rogue M180’s
Last week a friend gifted me a pair of Rogue M180’s. They were sold as 180’s and I received them from the original owner. Im guessing them to be 10-12 years old. They were used when first purchased for about 5 years sparingly. Since then they have resided on a flat dolly in a spare bedroom. The amps still have the original Phillips ECG 5751 and 5814A’s installed. The original EH KT 90’s are loose in a box with an octet of low hour Gold Lion KT-77’s . Years back when in use the owner contacted Rogue and stated they were too powerful for his room size and speaker selection. Rogue responded by recommending the GL KT77’s and suggesting that he could also lower the bias from 40ma to 30ma. I was provided the supporting emails dated September 2019. Here is my situation followed by my questions. I currently have a low power single ended system with Zu speakers. Second, the owner stated one might have a hum, but was not sure. He’s on his second complete system since and has a room full of gear he’s lost interest in and his memory is vague. Also back then he had power issues with his provider and stated they installed a new transformer on the street. So my questions are first, checking for any hum. My intent is to take a single amp and connect one JBL 4312 to it. Install the KT77’s, plug it in and listen for a hum and bias the tubes. Do I need the input open or shorted ? Or something else ? Second, the 12AX7’s being replaced by the 5751. I see there’s a mu of 70 Vs 100 with the 12AX7. Does that effect the overall output power of the amp or just change tone and distortion? FWIT I have 6-7 pairs of NOS Telefunken 12AU7’s but zero 12AX7’s. My intent is to check for hum without causing any damage. If a hum exists, I’ll ship to Rogue. In the short term if I’m successful, I’ll test drive with my existing Rogue RP-1, the JBL 4312A’s that are mint and the 26” Sound Anchor stands I have with them. And I’d like to get some Telefunkens to put in the 12AX7 positions. After that, there’s a pristine Rogue Hera that’s been inspected and re tubed by Rogue that I’ll ask to purchase before I start looking for speakers worthy of the pairing. Also I emailed Rogue for support a week ago and have not received a response. Thanks in advance for any feedback and my apologies for grammatical spaghetti, but I’m limited to an IPhone. Cheers , Mike B.
I co-admin a Rogue group on Facebook and I frequently comment: "JJ’s go right in the trash". Any of the Russian 12AX7 options are better (EH 12AX7 and 12AU7 are a bit too bright, though). Don’t pay a big-guy tube dealer $300 to $500 per pair. These days, it will be either very "questionable" NOS, or late production overstocked dregs from the 70s / 80s. Buy a couple sets of vintage "used, tests good" tubes from a smaller seller with a good track record. Example - I always liked Arizona Tube Supply. At least you’ll be getting what you paid for (used). Good vintage tubes should still last a very long time - not worth paying so much more for NOS, in my opinion. There should still be plenty of Telefunkens, Mullards and RCA black plates out there. 5751 work well in Rogue amps too. You want tighter imaging at the slight expense of some "size" and dynamics gusto? Use 5751. Upscale is an excellent choice for buying new power tubes. It’s worth their premium here - BUT you definitely don’t need the Cryo treatment or "ARC Select" / "Kevin’s Stash" premiums. I’ve tried those and they are no better than Platinum grade. Their burn-in process should filter out most of the problem tubes. I’ve bought dozens of Russian KT120 / KT88 from them over the years and NEVER had a single problem. The one EH KT90 I’ve had blow up on me (15 years ago) was supplied by Rogue! |
@mulveling Thanks for sharing your experience. I was thinking Brent Jesse, but I will definitely check out Arizona Tube Supply. In the Rogue RP-1 I rolled everything from Mullards to high grade Telefunkens. Same with the single input tube in my Had Inspire. But these were 12AU7’s in the Rogue and a 6JD/ecc88 in the Had. But my assumption is the sound characteristics will carry over in the 12AX7’s. Please correct me if I’m wrong. Of the American tubes RCA and Phillips were pretty good. It came down to Telefunken, Seimens and Amperex in that order with Telefunken my favorite. The Seimens CCa was second with the nickle plates and the Amperex next. What I found with the Seimens and the Amperex is the treble was too forward , where as the Telefunkens were smooth across the frequency range. I’m changing walls for my stereo and will be getting a new TV. Unfortunately the TV will be on the wall behind the stereo. But my room is 19’ wide by 28’ deep so I’ll be able to put the speakers 3-4’ off the front wall. I just removed a huge 3 sided cloth covered sectional from the room and came to realize how much it dampened the room. The guy that I got the gear from offed my a free pair of unused GIK wooden diffusers. My intent is to mount the tv, change to that wall and set up the system. Then I’ll play with the diffusers and experiment with bass traps and absorbing panels. My friend also has a commercial sound analyzer that’s in a travel case with mics and stands. I don’t remember the brand and I’ve not played with it. It’s older but probably still useful. Again , thanks for your wisdom. Cheers , Mike B. |
I've got vintage and NOS tubes from all of these same people sitting in boxes my cabinets. Priors from AZ, some of Brent's very best curve-tracer triode matched triodes too. Each has its own character, and depends on the rest of the system. While they sit in boxes hoarded away, JJs stored too, I'm still running later version PSVANES the past year solid with zero issues. A tad softer and fuller sound if you like that. @buellrider97 I say let all those stock large and small tubes burn in so you get the caps, diodes, resistors all burned in [first] on cheap tubes you'll pull and replace anyhow in a few weeks. |
Well I’m on day 2 and the harshness is starting to subside. Unfortunately I could not stand the JJ 12AU7’s any longer. Although they’re the gold pin version I just couldn’t take it anymore. I had turned the mid and treble settings on the JBL’s to 1 and it still sounded harsh. So I put in 2 pairs of Siemens nickel plates in the 12AU7 slots and ordered a trace curve matched pair of smooth plate 12AX7’s from Brent Jesse. With just the Seimens in it’s already more listenable and the Telefunkens will arrive next week. I will take your advice and contact Arizona Tube regarding some additional tubes. About 5-6 years ago I was at the Barrett- Jackson car show in Scottsdale and there was a big booth selling restored vintage radios and vintage tubes. My memory is foggy, but I can’t help thinking it was the vendor you mentioned. BTW I noticed the amps are biased at 35ma. , what do you guys run ? Cheers , Mike. |
@hiend2 Hi , I agree the RCA’s would be an improvement, probably quite significant. My Tekefunkens should arrive in a few days and I’ll replace the new production Tung Sol 12AX7’s. I have the system burning in on the dining room table. I used all the cables in my leftovers box, it’s quite an ugly scene. It’s all running through an old Monster power filter and discarded unbalanced interconnects. The speakers are on the table too, it’s quite comical. I’m getting moments of nice sound depending on what’s streaming. I’ve emptied the living room and got out my big Sound Anchor stands. They were damaged by dissolving Blue Dots and I have to clean and repaint. I’ll have to get some balanced IC’s real soon. Thanks for your input. Cheers, Mike B. |
@hiend2 Hi , how’s it going? So about 5-6 days ago I put a primo pair of Tekefunkens in the 12AX7 spot. They’re NOS , but they definitely needed some time. The amps had about 100 hours on them with the new tubes plus the upgrade. They are settling in nice. The Telefunkens replaced some new production gold pin Tung Sol 5751’s that actually sounded very nice. I became very aware when I replaced them with the Telefunkens as they are bright and grainy. I’ve left the amps on most of the last 5 days and they’ve come in nicely. The problem is now the speaker glare , but they’re just temporary. I did however order a pair of nos GE 5 Star triple mica black plate 5751’s from Arizona tube supply. I’ll try them upon arrival and see what happens. I sent an email to Rogue inquiring about 12AT7 and 12AY7’s. They would only say the circuit is optimized for 12AU7’s, but they ship with 5751’s. They didn’t respond at all to my second question about tone impact with the splitter tube Vs the 2 gain tubes. Any input would be appreciated. Cheers, Mike. What am I looking for regarding Jay’s Tube Lore ? |
The 12AX7 and 12AU7 slots have different roles and operational parameters. You would sub 5751, as a near-12AX7 equivalent, into the 12AX7 slot, NOT the 12AU7 slots. A 12AX7 (or 5751) is gong to struggle like crazy in 12AU7 slots, diving those big KT120 or KT88. You'll get higher distortion for sure. You won't hurt anything by experimenting in these slots, but best to stick to tubes with lower Rp (i.e. they can push more current) in those 12AU7 slots. Hell, even 12AU7 may be underpowered for this slot, which is perhaps why some of us report good results with 12BH7 sub. Many good 12AU7 subs have already been listed here. The 12AX7 (phase inverter / splitter) slot - you can experiment a bit more here. Besides 5751, 12AT7 and 12AY7 should be OK here. I've actually used 12AY7; it can sound pretty good (GE red "industrial" label 1964). I even once accidentally put 5814 (a 12AU7 sub) into the 12AX7 slots and it sounded decidedly fatter / colored, but also pretty euphonic. Took me a day to notice my error lol. The GE triple-mica black-plates (a.k.a. TMBP) 5751 are awesome tubes. Great choice! Very sweet sounding, but with great sparkle, dynamics, and detail. Fantastic mids. There's a special variant of it only produced in 1953 and 1954 which has "silver clips" crimping the little plate "ears" that poke through the mica wafters. I think these sound even sweeter than other TM BP's - but they're rare. And hard to spot from most photos. I've even mixed one of these with a non-clips version (the pair was electrically matched) and it carried most of the "silver clips" magic without causing a notable imbalance. Tubes are generally more flexible and forgiving than you might realize at first :) |
Gentlemen, again thank you for spoon feeding me. About 2 days after the amps came back, I pulled the 4 JJ 12AU7’s and threw in a quad of Seimens nickel plates. I have a quad of Tekefunken G-73 R’s yet to try. Unfortunately my RCA’s and Mullards , I’ve only 1 pair of each. I’m looking forward to trying the GE 5751’s when they arrive this week. I spent an hour reading Joes Tube Lore regarding 12AX7’s , very interesting. I have a couple caveats in my initial tube rolling. First the equipment lacks a proper set up as it’s all on the dining room table. Second I’m trying to like a pair of speakers that aren’t that good. But I’m getting some run in time and can get a partial idea of the SQ I’m striving for. I’m definitely being guided by the experience being shared. I’m coming to the conclusion that I want a larger speaker that’s “ MUSICAL “, that I can crank up and listen to while sometimes moving around. Being extremely price driven , I’m interested in the Tannoy’s , Fyne, MoFi 888, Cornwall IV’s ( not a fan of horns ), Tekton Moab. Unfortunately I’ve never heard any of these. Upscale Audio is about 3-4 hour drive from me. After I get this gear in a proper set up , and some balanced cables , I’ll schedule an appointment to audition some speakers. Also any recommendations for some balanced IC’s that a poor guy can afford, I’m all ears. I’m thinking a 1 meter pair for DAC to pre, and 2 meters from pre to amps. Please keep it coming! Regards, Mike B. |
That’s my leaning too - I love Tannoy DC’s for their mix of coherence, refinement, and detail. Haven’t heard Fynes; they can be viewed as a continuation of Tannoy, but losing of some of the old-world / traditional features of Tannoy Prestige along the way (alnico magnets, textile surrounds). There’s a WIDE range of sounds you’ll get from various Tannoy models (and probably Fynes too). If you want a BIG sound then that is (perhaps obviously) best manifested by the models with a 15" DC driver. The 12" DC can get close. But when you step down to a 10" DC, it’s a different beast - they sound GREAT in midrange, but they’re not gonna sound "big". With smaller DC drivers you’re either going to want to supplement with subs OR at least look for models that add a dedicated woofer to the main DC driver (as Fyne does with 702, 703, 704 lines like Tannoy used to do with Definition DC10, DC8 before them - and further back, D700 etc). There’s been much talk about the closure of Tannoy’s Scotland factory, and move to Music Tribe’s Chinese factory, since Behringer’s acquisition. Yes, even all Prestige drivers are now made in China! However, being curious, I finally bought a pair of loose Kensington GR drivers made in China - and plugged them into a definitely made-in-UK Kensington GR black edition. Frankly, I think these Chinese drivers sound better than UK - maybe not a fair comparison if the "black edition" drivers were tweaked differently. But the Chinese do sound better. And if you ignore sticker labels (and gold vs. silver metal colors), they look to be of exactly the same quality build - you would not be able to tell which is which!. |
@hiend2 ,Thank you for recommending the GE 5751’s, they’ve only 2 days , but it certainly knocked off the rough edges, without sacrificing the overall sound. @mulveling , Thank you for staying in this thread with your detailed input, I greatly appreciate your helpfulness. To everyone here , I’m at a point where I can’t go any further until I do a proper setup. Unfortunately we are signing contracts for a major kitchen remodel. This includes ripping out the cabinet soffits in the kitchen and bar, rerouting multiple outlets , water lines and overhead lighting. It will be raining powdered insulation ( whatever that grey crap is ). I’ll probably box it all up ( both systems ) until completion as to avoid airborne contamination of my gear, TT, speakers and records. I’ll be cooking in the laundry room, and eating in the garage with our two standard poodles. Upon completion, if I don’t have a heart attack, I’ll do to a proper setup. I still need cables and speakers. There’s no use trying more tubes till then. FWIT I had conversation with Terry London regarding some cables and he highly recommended a pair of Tekton Moab’s. As I said before I’ll hit Upscale Audio for an audition, and might go to Utah if I can’t audition somewhere. He has taken a lot of crap on this site for what he liked in the past. I’m guessing it will either be 15” drivers , or maybe the Tektons. I have ZU’s that I’ve yet to try and was told my them they would work fairly well, but I want to go BIG ( unfortunately on a budget ). I really pains me to spend $100K on a kitchen upgrade and once again the stereo gets put off. But if Mama’s not happy, nobody is. Cheers to all, give me about 8 weeks and I’ll reach out. |