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Post by pedrocols on Nov 11, 2021 10:41:31 GMT -5
My favorite 12au7 is the Baldwin. I have tried GE, RCA and Raytheon. I have a pair of these but haven't tried them yet. They are actually RCA Cleartops. These are the ones I currently use with my VTA-M125 monos. Baldwin by Raytheon Long Black Plate O Getter.
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Post by DavidR on Nov 11, 2021 14:12:26 GMT -5
I have a pair of these but haven't tried them yet. They are actually RCA Cleartops. <button disabled="" class="c-attachment-insert--linked o-btn--sm">Attachment Deleted</button>
These are the ones I currently use with my VTA-M125 monos. Baldwin by Raytheon Long Black Plate O Getter. <button disabled="" class="c-attachment-insert--linked o-btn--sm">Attachment Deleted</button> Raytheon made very GOOD tubes and the organ companies would pick the best of the best. I'm currently looking for a pair of Raytheon 6SN7GTB tubes.
Did you buy those from eBay seller DesireMe (Michelle) ? She has good tubes and is great to work with. I ask because she always has a ruler beside the tubes.
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Post by pedrocols on Nov 11, 2021 19:03:32 GMT -5
These are the ones I currently use with my VTA-M125 monos. Baldwin by Raytheon Long Black Plate O Getter. <button disabled="" class="c-attachment-insert--linked o-btn--sm">Attachment Deleted</button> Raytheon made very GOOD tubes and the organ companies would pick the best of the best. I'm currently looking for a pair of Raytheon 6SN7GTB tubes. Did you buy those from eBay seller DesireMe (Michelle) ? She has good tubes and is great to work with. I ask because she always has a ruler beside the tubes.
Yes.
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Post by DavidR on Nov 12, 2021 0:21:08 GMT -5
I believe you are out in western MA. Ever deal with Viva Tubes in Easthampton ?
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Post by pedrocols on Nov 12, 2021 9:15:37 GMT -5
I believe you are out in western MA. Ever deal with Viva Tubes in Easthampton ? Yes I live in western MA but haven't dealt with them. I live 40 minutes away from Bob Latino so I had the chance to listen to the amps at his home before I bought mine. I picked up my amps at his home so I did not have to pay for shipping. Bob is a great guy!
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Post by LuisV on Nov 12, 2021 9:19:05 GMT -5
Although not an amp, below are my tube rolling experience and thoughts thus far with various 6SN7 tubes in my Schiit Freya plus. I haven't found a tube that I didn't particularly like; however, some sounded more refined and or "color" the sound better than others... I'll do my best to describe what I heard. Before taking the plunge, I combed through various Freya tube rolling forum posts as I wanted to become more acquainted with the 6SN7 offerings and gain experience from other owners. Most owners indicated that the right pair of tubes have the most impact to the overall "sound" quality; therefore, quad sets aren't required; matched pairs are recommended though. After reading various posts and messaging a couple of Freya owners, I decided to venture down the rabbit hole... My observations are listed based on what was provided with the Freya and then in order of purchase / delivery. Besides the Tung-Sols and Electro-Harmonix quad matched sets, the rest were matched pairs installed on the right side of the Feya. Tung-Sol 6SN7GTB - Stock tubesDynamic, punchy with less of that "tube" sound, if that makes sense. I've seen / heard Youtubers call the sound signature of the Tung-Sols as the "new" tube sound, not warm; however, certainly not clinical nor cold sounding. They provide just enough "color", yet are different when comparing the sound to older tubes. They provide a wide soundstage, yet it is not as deep as some of the other tubes I have on hand. All in all a great sounding tube, nothing particularly "magical", just a nice sounding tube that is readily available at a decent price point. Electro-Harmonix 6SN7 - Matched Quad Set - Tube Depot - $23.95 / eachI enjoyed their 6922 in my Schiit Vali headphone amp, so these were the 1st tubes that I purchased for the Freya. They are extremely similar to the Tung-Sols; however, have less width to the sounds stage as they sounded ever so slightly "boxed in" in comparison. Don't get me wrong, the soundstage didn't suck; the presentation from the Tung-Sols was simply wider. If I didn't have the Tung-Sols to compare them to, these would be perfect as far as an inexpensive set of readily available tubes. GE 6SN7GTA with copper grid posts, "D" getter; 1950s - Tube Depot - $159 / matched pairSlightly less bass than the Tung-Sols; however, they are much warmer, so I'm starting to hear the "color" that I prefer. Call it distortion if preferred, but I'm starting to hear the "magic" of tubes and those sonic qualities weren't present with the Tung-Sols. The GEs have the same dynamics, impact, and wide soundstage of the Tung-Sols, so I decided to keep them on the left side, while testing the other tubes I have. No particular sound quality reason for that decision, I felt since they were also old / "NOS" tubes that they should pair better with the rest of the tubes I had purchased. RAYTHEON 6SN7GTB short bottle with side "D" getter and black plates - eBay - $38.93 / matched pairAfter letting them cook for a few days, I finally heard the "magic" I was looking for. They have a wider, deeper and taller soundstage. Smooth vocals, fantastic guitar... simply a better sounding tube. There is more presence to the music... just all around better. I regards to soundstage depth, it sounded as though aspects of the soundscape came from behind the speakers.... as in, a few feet behind the speakers... the speakers simply disappeared... they added more dimension to the sound than what I previously heard with the other tubes. With the other tubes the speakers also disappeared, but they weren't as dimensional nor deep as these. RCA 6SN7GTB with bottom getter and black plates; one dated May 1961, the other Nov 1963 - eBay - $47.93 / matched pairNice sounding tubes, but a step down from the Raytheon; these are more like the GEs, but not as refined. They still put a smile to my face, but the Raytheon's are superior. I'll need to do a longer A/B test, but after an quick comparison, I prefer the GEs over the RCAs as the GEs had more detail and presence to the musical presentation. CBS 6SN7GTB with 2-Hole black plates and bottom "D" getter; 1956 Week 22 - eBay - $59.33 / matched pairInitially reminded me of the Raytheon's, but after a quick A/B, they sounded more like the GEs; however, with deeper bass and although less than the Raytheon's, they have more dimension to the soundscape than the GEs presented. These are much warmer than the Tung-Sols and Electro-Harmonix, but not as "magical" as the Raytheon's. I prefer these over the GEs. I'll probably keep these on the left side once I finish listening to all the tubes I have; possibly as a round 2 type test. I have these on hand, just haven't gotten to them yet. Psvane UK-6SN7 factory matched - Grant Fidelity - $119.95 / factory matched pair Raytheon 6SN7GTB medium bottle with black plates, halo getter - eBay - $57.53 / matched pair Sylvania 6SN7GTA with 3 hole black plates; 1954 Week 13 - eBay - $89.93 / matched pair RCA 6C8G with 6SL7 adapter and cable - eBay - $92.50 matched pair Raytheon / Baldwin 6SN7GTB - eBay - $62 matched pair After listening to 6 different tubes, new and "NOS", below is my order of preference; however, as older tubes become more expensive and more difficult to find, I have two options for relatively inexpensive, great sounding and readily available tubes in the Tung-Sols and Electro-Harmonix. RAYTHEON 6SN7GTB short bottle CBS 6SN7GTB GE 6SN7GTA RCA 6SN7GTB Tung-Sols Electro-Harmonix Currently cooking the Sylvania 6SN7GTA with 3 hole black plates; 1954 Week 13. For more info on my room and the decision to head back to 2 channel stereo please visit here: emotivalounge.proboards.com/thread/57382/heading-back-2-channel@luisv, looking for your thoughts on these 6SN7 tubes. Have you had a chance to review them all? Is the Raytheon 6SN7GTB short bottle still your fav? Sorry for the delayed reply, life and work got in the way... In the end, I preferred the sound provided by the Sylvania 6SN7GTA with 3 hole black plates and Baldwin / Raytheon 6SN7GTB over the other tubes I tested. I posted my remarks here as well as the rest of my tube journey. emotivalounge.proboards.com/thread/57382/heading-back-2-channel?page=6I also compared a Node 2i, by itself as well as connected to a Bifrost 2 against a Cambridge CXN v2 and ultimately sold the Node 2i and Bifrost... so far, I like what I'm hearing from the CXN v2, but time will tell if I get that itch to go down the rabbit hole of trying other external DACs. emotivalounge.proboards.com/post/1076730/thread
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Post by DavidR on Nov 12, 2021 12:23:30 GMT -5
I believe you are out in western MA. Ever deal with Viva Tubes in Easthampton ? Yes I live in western MA but haven't dealt with them. I live 40 minutes away from Bob Latino so I had the chance to listen to the amps at his home before I bought mine. I picked up my amps at his home so I did not have to pay for shipping. Bob is a great guy! Yes, Bob is a great guy. He's maybe an hour+ down the Pike from me.
I've had good luck with Viva Tubes. Nice people. I snagged some NOS GE labelled Tungsram and German RTF 12AU7 tubes. Both are great sounding. They also will test your tubes for a reasonable fee.
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Post by DavidR on Nov 12, 2021 12:49:01 GMT -5
@luisv, looking for your thoughts on these 6SN7 tubes. Have you had a chance to review them all? Is the Raytheon 6SN7GTB short bottle still your fav? Sorry for the delayed reply, life and work got in the way... In the end, I preferred the sound provided by the Sylvania 6SN7GTA with 3 hole black plates and Baldwin / Raytheon 6SN7GTB over the other tubes I tested. I posted my remarks here as well as the rest of my tube journey. emotivalounge.proboards.com/thread/57382/heading-back-2-channel?page=6I also compared a Node 2i, by itself as well as connected to a Bifrost 2 against a Cambridge CXN v2 and ultimately sold the Node 2i and Bifrost... so far, I like what I'm hearing from the CXN v2, but time will tell if I get that itch to go down the rabbit hole of trying other external DACs. emotivalounge.proboards.com/post/1076730/thread I missed the update post. I have a tube buffer that I like to use for CDs. It uses 6SN7 tubes. I have a nice pair of Sylvania 6SN7GTB from maybe late 40's early 50s. They make a nice difference. I also have a pair of new production Tung Sol 6SN7GTB. I've been looking for a nice pair of Raytheon on eBay but haven't seen anything that entices me.
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Post by leonski on Dec 14, 2021 15:40:18 GMT -5
I would add one note to folks that have other similar amplifiers....
Solid state diodes have a lower voltage drop than a tube rectifier and of course don't have a filament that requires power or needs to warm up.
Eliminating the significant amount of heater current some rectifiers tubes require may mean that your power transformer runs a bit cooler.
And, because of their lower forward voltage drop, when you replace a rectifier tube with solid state diodes, you will raise the voltage output on the high voltage supply... You will also lower the output impedance of the power supply - which may otherwise improve performance or alter the way the amp sounds.
Specifically the increase in voltage may increase the output power on the amplifier... And it WILL require you to readjust the bias on some tubes...
However, if the high voltage on your amplifier was already near the limits for your output tubes, or of the high voltage filter capacitors... Replacing the rectifier tube with diodes could cause you to exceed their maximum limits... This could cause the output tubes to fail prematurely or could cause the filter caps to fail outright... (When making modifications like this it's never a bad idea to check the high voltage on the terminals of the power supply caps with a meter... CAREFULLY.)
Also note that, with a tube rectifier, which warms up slowly, the rectifier and the output tubes tend to warm up at similar rates. So, since the voltage of the power supply, and the load presented by the output tubes, come up together, they tend to smoothly balance out. But, when you replace the rectifier tube with diodes, the high voltage may "jump up" briefly when you turn the amplifier on... (The high voltage supply comes up immediately, and may rise somewhat abruptly, until the output tubes warm up and load it down again.)
You need to be sure that this spike in voltage doesn't significantly exceed any maximum ratings - or it could cause the amp to fail prematurely.
AS LONG AS THIS IS AN "APPROVED" MODIFICATION FOR YOUR AMPLIFIER THEN THIS SHOULD NOT BE A PROBLEM.
However, you should not make changes like this to other amplifiers that use a tube rectifier unless you know that it's safe, or thoroughly understand how the changes will affect your particular model...
The diode mod is a well known and documented mod for Bob’s amps. See the Dynaco forum for specific details. Cheers, Yes, the VTA folks.....Bob Latino, in particular are OK with this mod. But ONE thing not covered? Back in 1965 or so, when the Dynaco Stereo 70 was 'big' and selling in large numbers, your HOUSE probably had 110 vac at the outlets. I personally called it 'One-Ten' for years after that was probably NOT the case. These day? I see 120 as considered 'normal'. My house? 117 thru 119 most of the time with large drops to maybe 115 or LESS during the peak demand part of the hottest days. At THAT point? I tend to shut stuff OFF and pull plugs.......just to be safe. What does this have to do with anything? Well, your transformers are 'fixed' ratio. So, a 5:1 step 'up' transformer may have put out 550v, but NOW might put out closer to 600. Likewise? the HEATER part of the transformer might have put out a nominal 6.3 or so, but NOW? Might be nearing the 'danger zone' over 6.6 or 6.7VAC. I've heard the new VTA kits have a choice of input voltage of 117 or 120.....This will, I suspect, give the correct B+ IF wired correctly. And help with tube life, maybe?
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Post by audiobill on Dec 14, 2021 16:43:56 GMT -5
Bob recommends the use of a variac, as discussed before.
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KeithL
Administrator
Posts: 9,976
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Post by KeithL on Dec 14, 2021 18:12:55 GMT -5
The simple fact is that, in most areas, your power company is not obligated to deliver an exact voltage. First it varies by area... where I used to like in New York our line voltage was usually around 125... which is a bit high. But, beyond that, the actual service agreement in most places allows for quite a bit of variation. (In many areas, +/-5% is considered acceptable, and up to +/-10% "short term"...)
Back in the days when tubes were current technology the variations were sometimes even wider. But, for that reason, virtually all appliances, including audio amplifiers, were designed to tolerate a relatively wide range. (You didn't run power tube with a 600V max rating at 590V and, if your B+ was 525V, you used 600V filter capacitors.) (Most older amps now use cathode bias - which means that the bias on the output tubes automatically compensates for changes in plate voltage.)
Nowadays, in an attempt to squeeze every last bit of power out of everything, designers have a habit of running everything "closer to the red line". And, unless you move to regulated power supplies, this makes them more critical of changes in the line voltage. It's easy to regulate the bias and filament supplies... but takes a bit more doing to regulate the plate voltage.
(And, in a really cool design, you should use regulated DC for the filaments.)
I would add one note to folks that have other similar amplifiers.... Solid state diodes have a lower voltage drop than a tube rectifier and of course don't have a filament that requires power or needs to warm up.
Eliminating the significant amount of heater current some rectifiers tubes require may mean that your power transformer runs a bit cooler.
And, because of their lower forward voltage drop, when you replace a rectifier tube with solid state diodes, you will raise the voltage output on the high voltage supply... You will also lower the output impedance of the power supply - which may otherwise improve performance or alter the way the amp sounds.
Specifically the increase in voltage may increase the output power on the amplifier... And it WILL require you to readjust the bias on some tubes...
However, if the high voltage on your amplifier was already near the limits for your output tubes, or of the high voltage filter capacitors... Replacing the rectifier tube with diodes could cause you to exceed their maximum limits... This could cause the output tubes to fail prematurely or could cause the filter caps to fail outright... (When making modifications like this it's never a bad idea to check the high voltage on the terminals of the power supply caps with a meter... CAREFULLY.)
Also note that, with a tube rectifier, which warms up slowly, the rectifier and the output tubes tend to warm up at similar rates. So, since the voltage of the power supply, and the load presented by the output tubes, come up together, they tend to smoothly balance out. But, when you replace the rectifier tube with diodes, the high voltage may "jump up" briefly when you turn the amplifier on... (The high voltage supply comes up immediately, and may rise somewhat abruptly, until the output tubes warm up and load it down again.)
You need to be sure that this spike in voltage doesn't significantly exceed any maximum ratings - or it could cause the amp to fail prematurely.
AS LONG AS THIS IS AN "APPROVED" MODIFICATION FOR YOUR AMPLIFIER THEN THIS SHOULD NOT BE A PROBLEM.
However, you should not make changes like this to other amplifiers that use a tube rectifier unless you know that it's safe, or thoroughly understand how the changes will affect your particular model...
Yes, the VTA folks.....Bob Latino, in particular are OK with this mod. But ONE thing not covered? Back in 1965 or so, when the Dynaco Stereo 70 was 'big' and selling in large numbers, your HOUSE probably had 110 vac at the outlets. I personally called it 'One-Ten' for years after that was probably NOT the case. These day? I see 120 as considered 'normal'. My house? 117 thru 119 most of the time with large drops to maybe 115 or LESS during the peak demand part of the hottest days. At THAT point? I tend to shut stuff OFF and pull plugs.......just to be safe. What does this have to do with anything? Well, your transformers are 'fixed' ratio. So, a 5:1 step 'up' transformer may have put out 550v, but NOW might put out closer to 600. Likewise? the HEATER part of the transformer might have put out a nominal 6.3 or so, but NOW? Might be nearing the 'danger zone' over 6.6 or 6.7VAC. I've heard the new VTA kits have a choice of input voltage of 117 or 120.....This will, I suspect, give the correct B+ IF wired correctly. And help with tube life, maybe?
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Post by leonski on Dec 14, 2021 18:40:04 GMT -5
Here in SD, the highest I have noted for house voltage is about 121 with the LOW end being about 114. Much below 114 I'd expect a brown out....... I can't quibble with 5%. =120+-6 volts.....
As a matter of fact? We had a surge about 45 mintues ago which triggered the power conditioner to shut down. I left EVERYTHING off. My computer
and most other stuff didn't twitch....but the TV / amps sure didnt' like it......y power ocndiitoner shuts down about 135vac........\
But we are also in the middle of a pretty good blast of rain....now nearly blown thru.....but may persist for a while yet.
My point was NOT that voltage is 'inflexible' but rather the 'norm' has changed over the last decades...and upward.
What the power compnay REALLY cares about? FREQUENCY. US STaandard of 60hz is very rigidly enforces to I'd guess 0.1% or better. If all sources wern't synched up to
a very high standard a LOT of power could be wasted or perhaps other problems.....
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Post by leonski on Jan 14, 2022 19:28:22 GMT -5
Roughly 35 years ago, I took out (on consignment) a California Audio Labs tube analog CD 💿 player from a high end audio salon, using only a credit card 💳 as collateral. I played with the thing for a day, pitted against a run of the mill Magnavox player, and was unable to hear an iota of difference between the two. The ONLY difference I could come up with was a grand and a half difference in the price tag, and the identical remote from the CAL, later attached to a cheap CD player on a shelf at my local Sears. Aren’t credit cards great 👍. Bill I'm not certain about 'analogue CD player'......And after a couple beers at your Saloon? I'd expect 'em all to sound alike, anyway! But I had a similar experience in about '83 or '84 when I bought my Philips / Magnevox FD1000 14 bit 4x oversampling player. One of the first models on sale in the US. I bought the LAST ONE in the store. Went to a High end store and found a VERY expensive CD player. It was IDENTICAL in every button / control to a much less expensive player I think I saw at THAN 'Pacific Stereo'....Much later? Some company 're-shelled' an OPPO player and hit you with 4x or MORE the OPPO price......Idential machine... When I made the Mistake of buying a CB840 player? ALL in hte line used the SAME Sanyo transport. From the entry level to my top-line '840.......
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Post by leonski on Jan 14, 2022 19:32:39 GMT -5
The short answer is that they are recorded differently...
Most older jazz albums feature acoustic instruments and are recorded rather simply using a few microphones...
Most rock albums feature at least some "electric instruments" and are recorded through the mixer or console... And, to be blunt, those jazz albums were just plain mixed to sound "mellow"...
While most more modern rock albums are already subject to a wide variety of special effects between the microphone and the recording...
And they're mixed to sound crisp, and sharp, and for some of the instruments to have bite to them...
As a result of both most rock albums have more higher order harmonics already...
The mix has a LOT more to do with how a recording sounds than many people seem to think. (If you've ever made a simple recording of a live show... then you know that it rarely sounds anything like the show itself or the professionally mixed version.)
The single biggest part of that "tube magic" is an extra helping of second harmonic distortion... That's the part that makes voices sound fuller and smoother and instruments sound smoother and more liquid... And you've got the monotonic distortion profile... which makes the louder parts sound smoother and less harsh...
The answer to your question is pretty much the same as the reason why yellow sunglasses make a warm sunny day seem even sunnier and warmer...
But they don't usually do the same thing at all for the LASER lighting at a rock concert... And you generally wouldn't want to wear them while watching TV either...
Rock recordings tend to start out with more higher harmonics and a harsher sound... Therefore they don't "benefit" nearly as much from a little added "warm schmaltz"...
You're not going to hear those extra 2nd harmonics over the sound of a fuzz guitar...
You're also not going to hear them over the pile of 2nd harmonics already added to Blue Bayou by the Aphex Exciter... But you might notice them on a clean jazz recording... Especially if it sounds a little dry to begin with because the recording was done with very close microphones.
Why is this? When I play jazz it is always on vinyl. Of course I have some vinyl for rock and blues from before CDs. Why is it that my jazz records always sound like 'magic' with my tube gear and the rock and blues stuff is 'same old' ? - Just nothing special at all. The jazz albums are probably as old as the rock and blues so its not a matter of old vinyl vs new vinyl.
Keith? Please don't forget the 'Loudness Wars' where most remasters were RUINED by poor dynamic range and 'crushed' highs..... I'd expect if you went thru EVERY different version of say.......Dark Side Of The Moon......you'd end up BACK at the first US or UK issue....probably sounds better than most later 'remasters'..... www.npr.org/2009/12/31/122114058/the-loudness-wars-why-music-sounds-worse
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Post by DavidR on Jan 14, 2022 21:33:43 GMT -5
So I picked up a pair of Raytheon 6SN7GTB short bottle with black plates and side 'D' getter to compare to the Sylvania 6SN7GTB I been running in my Yaqin SD-CD3 tube buffer. I believe the Sylvania are ~1948 and not sure with the date codes on the Raytheon. Raytheon tubes are typically considered the cream of the NOS tubes. The tube buffer does 'smooth out' CDs and is needed with many older CDs that are un-listenable without the buffer. Otherwise it does little to the sound. I was using my Emotiva ERC-3 witch is hooked up RCA interconnects to the buffer/unbalanced and also balanced interconnects. I want to say the bass and highs are preferred/better thru the buffer. I listened to 3 CDs and really don't hear much difference between the two sets of tubes. If I HAD to pick as of now I'd say I prefer the Sylvania.
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Post by DavidR on Jan 18, 2022 12:48:29 GMT -5
Did you ever try Raytheon tall bottle 6SN7 tubes?
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Post by LuisV on Jan 18, 2022 13:24:48 GMT -5
Did you ever try Raytheon tall bottle 6SN7 tubes? <button disabled="" class="c-attachment-insert--linked o-btn--sm">Attachment Deleted</button>
Not sure there is a "tall" bottle... I could be wrong though. Pictured below... Baldwin, Raytheon, Sylvania and Raytheon with side getter, considered a "short" bottle. The other three had the halo getter, considered a medium bottle, and had black plates. After my tests, these were my favorite four tubes. Opinions of these 4 tubes: emotivalounge.proboards.com/post/1062667/threadOverall list: emotivalounge.proboards.com/post/1062048/threadI'm currently baking in a pair of Shuguang Treasure CV181-Z:
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Post by DavidR on Jan 18, 2022 17:17:34 GMT -5
Uuuugggghhhhhh I guess I got it wrong as I bought a pair of Raytheon short bottle with the square/D side getter (which I thought was the one you like the most) and I find I like my Sylvania 6SN7GTB better. The Raytheon above (that I call tall bottle) is, IIRC, a 1955 with square getter. I may try those.
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Post by leonski on Jan 18, 2022 17:56:49 GMT -5
David? Would you like contact information to my medium?
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Post by DavidR on Jan 18, 2022 18:47:36 GMT -5
David? Would you like contact information to my medium? medium??
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