Gz34 vs 5u4. Rectifier tubes mostly work until they don't.

Gz34 vs 5u4 New posts Search forums Subscribe. No need to replace it unless you are getting low B+ readings or other symptoms. This is also one of the coolest looking tubes I have. My 1965 Super Reverb has a 5U4GB and that sounds much better than a GZ34 in that particular amp. Also, the ability to Firestorm wrote:The power transformer will certainly support the GZ34, which draws less heater current than the 5U4, but the GZ34 will raise the voltages in the B+ supply. Wondering if it is ok to use a 5y3 or 5u4 in place of a 5ar4 The 5Y3 and 5AR4 (GZ34) are at opposite ends of the spectrum of the various pin-compatible rectifiers. 95 . The 5Y3 (a real one) is built like a smaller version of the 5U4 with a single flat loop of filament that goes up through the middle of the plate enclosure, over the top of the support mica and back down again. The RCA 5U4 and 5Z3 I have an Audio Note Kit 1. The 5U4 has a filament draw of 3 amperes. Metal-Base vs. The Mullard GZ34 is widely regarded as the best of those tubes. 5r4 5u4g와 유사한 직열형 정류관으로 허용 플레이트 전압이 높지만 입력필터 콘덴서의 용량이 낮아 5u4g 대용으로 사용 할 경우 특성을 검토 한 후 사용 I'd like to try the new ACME 274B tubes in place of the current 5U4G tubes in my Line Magnetic 210IA amplifier IF the former is compatible with the latter. Can I use either the 5U4GB or GZ34 interchangeably? Is there a reason to use one over the other? Pros/Cons? Any advice or suggestions welcome. konkret, ohne weitere Angaben zur Schaltungsumgebung kann man nicht klar sagen, ob die Röhren austauschbar sind. hx = Hexode Unit. com/aornicreviewsA nice look at my descent into tube rolling madness. The chart is most useful when you use it as a guide to the relative voltage drops of different rectifiers. Headphone Amps (full-size) Thread starter Dubstep Girl Start date I stuck a GZ34 in my 1972 Princeton Reverb (I think #AB1270) which calls for a 5U4GB rectifier tube. With "free" comes inpurities. D. Radio tubes are valves. The IF one wants to run a different recitifer tube in either case---whther the orignal is a 5U4 or a GZ34, the 5V4 mentioned above is a better option for replacing the GZ34and a 5Y3 will yield even lower voltages. Metal-base 5AR4 are expensive rectifier Rectifire tubes:- 5U4 GB RCA- GZ34 MullardAmp:- Fender DR Silverface 73Guitar:- Fender Stratocaster 62 CS with Fat 60 pickups by JosephinaEffects- Ts9- Blues I’ll add that a fantastic tube is the KR Audio Riccardo Kron Anniversary Special Edition 5U4G. Don't know if the audio will work out but I can hear the differences. Dubstep Girl's Massive 5AR4/5R4/5U4G Rectifier Review/Comparison! I have been wanting to create this thread for quite some time now, since Home. Parts arrived on time, now installed and working fine. The 5AR4 or GZ34's are similar, but sounds a bit more 'rounded' than the 5AS4. However, there ARE two great British 5U4G and I have several of each on hand and they are NOT for sale! First is the much-revered GEC U52: The other great one is the 1940's/50's Brimar 5U4G: And if Ladekapazität: GZ34 40µF; 5U4G 60µF - max Ia; GZ34 250mA, 5U4G 140mA - max Ua; GZ34 2x450V; 5U4G 2x540V Ausserdem wird aus den Datenblättern ersichtlich, dass der Ri der GZ34 nur etwa die Hälfte beträgt als der Ri der 5U4G. g. One solution for this is to add 100 ohm/10W resistors in series with each 5V4 plate, or add a bit of resistance in the B+ feed. The PT is wound to compensate for the additional voltage drop across the 5U4GB rectifier tube by having a higher HI-V AC potential from the start. Non-Metal-Base 5AR4/GZ34. arnold58. Be sure to check with an amp tech before swapping different tubes. 市場上的膽整流管大慨分為 5ar4、5r4、5u4、5y3、6x4 等, 而當中電壓是略有分別, 讀者使用或更換時, 應留意說明書上是否共用。筆者就略談3支靚聲和耐用的整流管, 好讓讀者有個參考:~ I have never heard of any "consensus" between 5AR4 or 5U4. What happens is a GZ34 at start up will source so much The GZ34 is equivalent to a 5AR4, specs are 2 Amp @5V heater, 60uF max 1st Cap, good for about 160mA DC with an internal resistance of about 175 Ohms causing about a I understand the whole reason for going from the 5U4 to the 5AR4 is the direct heating of the 5U4 shortens the life of the output tubes whereas the 5AR4/GZ34 is much But the biggest difference is that the cathode of the 5AR4 is indirectly heated, so it takes some time for the B+ to come up to full value. p = Pentode Unit. I try each one in any build w/ a recto socket and there's no telling which one will sound best. This sucker has 3 micas and a "girder" in it. I also have a fat glass 5ar4 GE labeled Mullard and current issue Sovtek 5ar4/gz34. Starting with a 5U4GB, Sovtek's datasheet (linked HERE for convenience) states: I am not sure what the exact difference is between the GZ33 and GZ37. A few can use a 5u4 if the OT will handle the heater current. VOLTAGE READINGS. GZ34 is the English designation and 5AR4 is the American designation for the same tube. The 5AR4 needs two amps from the PT, and the 5U4G requires three amps. The plates are spot welded and sutured as well. The 5U4GB rectifiers draw more current and has more low wattage breakup than the GZ34/5AR4 in lower wattage amplifiers so maybe try that rectifier tube. 9 17 250 450 low Vdrop 5U4/5Y3 5AS4-A 5T 5 3 50 275 450 improved 5U4 5AU4 5T 5 3. There is a slight difference in voltage, I think it's about 20 V, but it probably won't make a difference if you're using an amp with EL34s through KT88. Availability. Huge base also. GZ 34's and 5U4's will stand up to higher 看完作者一篇大比拼之後,再次拿出鐵座 gz34 與黑座再作比較,鐵座在平銜度方面與黑座有少許分別, 鐵座全頻去得較盡,音色偏冷,人聲鼻音較重,動態強橫,高頻通透. " The GZ37 is a direct replacement for the 5U4 when you perform the double secret modification. It's a free internet. Rectifier tubes mostly work until they don't. Post n°1; gz34 vs 5y3 vs 5u4. 7 46 250 450 long life 5U4 (High Famp) 5DJ4 8KS* 5 3 44 300 600 redesigned 5U4 (higher volts) 5R4-G/GY 5T 5 2 67 250 750 ruggedized 5U4 (higher volts) 5AR4 GT型（Φ33mm）8脚高真空旁热式全波整流管 等效管GZ34；类似管GZ32，GZ33（英，Mul. The 5U4GB allows the B+ to temporarily jump to 540vdc, the GZ34 more or less climbs and settles on the steady state 473vdc voltage, and doesn't over-shoot it. Joined Jan 12, 2008 Messages 1,472 Reaction score 16. Some amps need a big rectifier like a GZ34 but most will work fine with 5R4s or 5v4s. 5ar4和5u4g整流后接入的第一隻濾波電容的容量許用最大值也不一樣的，5AR4可以用的比5U4G大一些， 5AR4手冊可以用到60uF，5U4G只允許用到40uF。 如果原電路是按照5AR4來設計的使用了60uF的濾波輸入電容，插 5AR4 / GZ34 Rectifier Tubes are in stock and ready to ship! A recent customer comment: That went smoothly. Forums. Rectifier Tube Comparison difference between 5U4G and 5U4GB. GZ34 of 5U4GB ? GZ34 of 5U4GB ? Gestart door arnold58, 5 januari 2015, 22:01:32. Jul. The difference in sound quality is usually due to the 5U4G: A relatively firm rectifier often found in mid-sized Fender blackface and silverface amps. The 5V4 is closer to a 5AR4 but drops 10-20 volts more in a typical amp. Reply. Head Gear. It runs hot in some This is why the 5AR4/GZ34 would be better at low AC Mains voltages. dutch or uk made real deal old stock gz34’s are To add to the confusion, I've also heard that the PT's used in PR's differed in height between those that took GZ34's and 5U4GB's. Can I swap my 5U4 with a 5AR4? The answer is Yes and NO. The biggest change I have noticed so far was going from a Raytheon 5U4gb to a 2/59 US Army Coke bottle RCA 5U4G I think the 5U4G and 5U4GB are interchangeable I also like the JAN Sylvania 5931. GMT+8, 2025-4-4 08:13, Processed in 0. When I asked him about that today, he mentioned he just had those on hand and they were inexpensive. You can substitute lots of tubes, as long as you observe the peak inverse voltage and current limits, and it's good to pay attention to filament current draw too (e. Is it the difference in B+ or is it the different tube? The schematic for the 69 (AB568 circuit) calls for a 5U4GB, however it came to me with the 5AR4/GZ34 installed. The WE 274b and GEC U52 are really out of the "safe" range wrt uF. Roy Johnson 24. I believe that the GZ37 requires a lower input cap value on the quad cap than the GZ33 but customers tell me that both work well in the VTA amps. rfbro Posts: 27 Join date: 2014-12-28 Age: 69 Location: Vancouver WA. FULL-WAVE RECTIFIER. jp An often asked question. I previously liked the 5R4 but Differences between 5U4G and GZ34: 5U4G: Direct heating GZ34: Semi-indirect heating With some jukeboxes (Rock-Ola, Seeburg), the following effect occurs when using the GZ34: If the jukebox is in "standby mode" and a song is selected, the selected song starts very quietly. Don't use the 5U4G, it takes 3A heater current and the PT is only designed for the 2A that the GZ34/5AR4 needs. To be clear, the amplifer comes stock with 5U4G tubes. So I started to poke around various datasheets and I am hoping to gain some clarification. For what it is worth, I prefer the Having a preamp with a tube rectifier spec 5AR4 / GZ34 I do notice a difference in sound quality between the stock Sovtek and a NOS Amperex. What happens is a GZ34 at start up will source so much 5AR4/GZ34 5DA* 5 1. Don Well-known member Boogie Supporter. Rectifier tube (GZ34/5AR4, 5Y3GT, etc. ,G管）。小型高性能整流管，适于较大电流（250mA）电源整流用。适宜垂直安装，工作时必须有良好的通风。 The Weston Tempest (old KT88/ class A version) currently use 5R4W. In Stock; USD $299. 100 (two tubes are off). It has a neat brown base too. jaymanaa RIP 1961-2018. That means a 5U4G could draw more than a 5AR4 circuit was designed to handle, but not vice-versa. Gebruikersacties. New posts Search forums. The big difference is the 5U4G filament draws over 50% more than the A5R4. 09 2. Thanks! Feb 2, 2011 #2 ; muchxs Doctor of Teleocity. 8A, so the same caveat applies. The PT in that amp was cranked up a little when Fender went to the 5U4, so you'll likely see something around 485VDC on the plates rather than the 460VDC on the schematic when you Patreon: https://www. What's the difference between the 5R4W and the more popular 5U4G, 5AR4? I heard from tube (shop) keepers that if the amp uses 5R4W, the 5U4G and 5AR4 tubes will be compatible. It's a neat looking tube for sure! It's very tall and has an ST shaped bottle (it has a shoulder). 9A (for GZ34 - 355 53KU - 352 5U4 - 350 5V3A - 349 5Z3 - 340 My favourites included GZ33 and 5Z3 - top and bottom - as well as 5U4 which was right in the middle. 5r4gb, 2a filament draw and more sag than a GZ34 . In fact, he said that early MC30's he's seen came with the RCA 5U4g's (big gz34 vs 5y3 vs 5u4. The drop in B+ voltage is significant - with a GZ34 and a 47 ohm, your B+ is dropping by 35V. I'm sure Mesa will sell you their brand of 5U4GB, so the real question is if the amp design will accommodate the 5AR4 / GZ34 vs. What's new. GZ34/5AR4 question through the meaningless drivel you and a few other irrepairably damaged individuals perpetually vomit up at every opportunity. This would make sense, since the PT used Jim, There are a lot of rectifiers with the same pinout as the 5U4. This would make sense, since the PT used with the 5U4GB would be wound hotter to achieve the same B+ and also be rated for 1A more heater current on the 5V winding. I prefer indirectly heated types (5AR4/GZ34) if the circuit is willing. I like the tighter tone with less sag. 本帖最后由 第尾才子 于 2016-8-15 13:22 编辑 音响封神榜三十：5u4系列整流管的比较 大神常爱说整流管是会对声音有影响的, 这是因为不同的整流管内阻不同一影响电压及其稳定性，這一點是肯定的。因此, 大神如果老实的多不敢用来与硅管比较。以下是某大神的”报告”, 信不信由你。 5Z3P vs 5U4G vs 274B. 5AR4) is the skinny bottle 5ar4 Mullards. New posts New media New media comments New profile posts Latest Would changing the rectifier to a GZ34 -- or even installing a new 5U4GB -- tighten things up? Any other changes that I'd have to make? Other than the caps/tubes, the only changes I've made were disconnecting the ground switch, installing a proper power cord, and removing the 1200 pf caps from pin 5 of the output tubes The power transformer is wound for a 5U4GB rectifier which means it can handle the extra filament current of the 5U4GB. Narrow By. I have read that the GZ34 rectifier increases voltages though, and that this can be The MC30's came with the 5U4. Hence, I've been cautioned against using it since it *might* operate some of the downstream I'm getting just shy of 330-0-330V from my PT. A push-pull EL34 amp will run the ever living snot out of a single GZ34, and it will make a 5V4G scream for mercy. Home; The "Assembly Instructions" for the Dynaco Dynakit Stereo 70 list on page 10 tubes 5U4G and 5U4GB as suitable replacement for the GZ34 . I understand that the GZ34 is about 50 ohms internally, so a 47 ohm is getting it to intermediate with the 5U4, which is reputed to be about 150 ohms internally. You can run EL-34s with the 5U4GB, but the manual says only at 60 watts vs. t = Triode Unit. rfbro. Headphone Amps (full-size) Thread starter Dubstep Have three Thu 5U4GB had a lower operational steady state B+ voltage, from memory around 440vdc, but the GZ34 steady state is around 473vdc. 黑座音色非常像真,傑出伸展中高頻,聽男女聲都全冇沙石,豐厚低音,更重要的是 I suppose some JTM50/JMP 1987 transition thing. B+ rises very quickly with this tube. For a Class A/B amplifier (which I believe is the case with the Heathkit AA-111), you may actually be able to hear a difference between the two types of rectifiers because the plate currents vary depending on how hard you are pushing the tubes. RCA - chord 0:58- nood The GZ37 is a fairly high-drop rectifier, similar to a 5U4. 95 USD $25. Apr 22, 2021 #9 ; schmee Telefied. With the GZ34's the B+ is 425v and the amp has a very taught, muscular robust sound. Maar wat wel een punt is, is dat de spanningsval over de GZ34 kleiner is. Yep, they are the same. tr = Tetrode Unit. HM = Heater Tap. 9. Fender used virtually the same PT in late Vibro Champs and Princetons. Philips-Miniwatt GZ34 鐵座，市價約 10 - With luck, the OP has been able to discern an answer to his 5U4GB vs. ) Preamp tubes (12AX7, 12AT7, 12AU7, 6DJ8, etc. The big difference is the climb in voltage on startup. TERMINAL ABBREVIATIONS: H = Heater End (Unpolarized). It is interesting that the GZ37 is listed, because the first PS cap on the Chenin is 33uF, well above the recommended value I can confirm that a 5U4G will *not* fit under the cover of a stock LS100. So maybe the Mark V would tolerate the 5U4GB in the 45 watt mode. Omlaag Pagina's 1 2. My own EL34 amp rocks a pair of 5U4GB rectifiers to provide ample The 5u4 & GZ34 is a key part to the Blackface sound & feel. It only needs 2A and will give slightly more compression than the 5U4G. Dyna ST70's beat the rectifier into the dirt. Thanks for stopping by. You're a YP. With the GZ37's the B+ is 400v and the sound is more relaxed with more breath and ease but also slightly softer around the edges. h. It The 5U4 and GZ34 are pretty much equal but the 5U4GB will drop the B+ output voltage by about 40 volts. 2) Would an SS rectifier that draws nothing give me even more power than both 5U4 and GZ34, and give even more potential for cleaning up that bass department? Likewise, In a tubed preamp, like my Dynaco PAS, what kind of results Mullard GZ34's, manufactured in the Blackburn plant, have a well earned reputation as the best sounding and longest lasting. NO Mullard 5U4G. I don't have a Tremoverb, though. IC = Do Not Use (Internal Connection). If it was me, I would Amperex 5AR4 / GZ34 | 1966 | F32 B6D3 Blackburn Factory Philips Miniwatt GZ34 Metal Base | 1957 | TV2 57A Crossor 53KU | Home. The 5U4 draws 3A vs. Good morning, What would be the draw backs of going from a cheap GZ34 to a NOS RCA 5U4? Iam tired of the crappy new GZ34's as they dont last long at Home. Print. 5U4G / 274B: A 5AR4/GZ34 requires 1. Please don't forget the most important difference. In my Allnic phono stage it’s another world, far better than any 5AR4 or 5U4G I’ve tried, including the vaunted Cossor CV575 from the early ’50s. 5U4GB. Vorige topic - Volgende topic. I did a partial "blackfacing" on the 69, changing the bias pot to adjustable fixed, adding the 220K grid leak resistors for the 6L6s, and changing the PI plate load resistors from 47K to 100K and 82K. 5AR4 / GZ34 Tubes ; 5U4 Tubes ; 5Y3 Rectifier Tubes ; 6CA4 / EZ81 Tubes ; 6X4 Tubes ; Other Rectifier Tubes ; 8 Products . Butyou won't see 20 volts of drop from a 5Y3GT vs 60 on a 5Y3. It drops voltage a bit less than a 5U4GB. Jvalvano Interesting results. Feb 9, 2013 #4 Epay for the WE tube, they bring The 5U4G and 5AR4 tubes are interchangeable to a certain extent. Dubstep Girl's Massive 5AR4/5R4/5U4G Rectifier Review/Comparison! (Rectifer Tube Rolling thread) Home. I thought I'd try a 5U4GB to lower the plate I have GZ34, GZ37 (expensive), 5U4, & 5Y3 (for small amps) as well as a SS plug. mvm AB568 circuits tend to like 5U4GB rectifier tubes. Joined Feb 12, 2011 Posts 32,769 Location Around. Equipment Forums. Reactions: JRapp. Consulting the rectifier tubes cheat sheet, it looks to me like the 5U4GB would be the best choice if I used a tube rectifier. It can often but not always sub for a 5AR4. Joined Sep 26, 2015 Posts 3,527 Location Maldon, England. Feb 8, 2013 #1 Hi all but the 274B will lighten your wallet (and last forever). The difference is noticeable, not only in audiophile gear, but even in old tube musical equipment like Fenders, Marshalls, etc. Could not tell difference. 9A filament current. a darker, more opaque sound from the NOS tube. I found the 5U4's to 另外，5AR4 比 5U4 電流小，原本用 5AR4 者，也最好別用 5U4 替代， 不過，原本用 5U4 者，倒是可用 5AR4 替代 (但電流可能稍不足)。 也就是說，5AR4 可替代 5U4，但 5U4 並不適合替代 5AR4 (除非器材規格上許可)。 5AR4 經典名管 1. The PO put in the JJ GZ34's in specifically for the slow start feature of the GZ34 to save fatigue on the output tubesno other reason. A 5Y3 is a very droppy tube. The only direct experience I can offer is with the Heartbreaker. This is perfectly fine. Joined Jun 2, 2003 Posts Dubstep Girl's Massive 5AR4/5R4/5U4G Rectifier Review/Comparison! (Rectifer Tube Rolling thread) Home. Within each of the major families, there will be a slight variation in uF, e. The Sovtek actually sounds (sounded) better than the NOS Amperex, open detailed and bright in a good way vs. Any comments on running the 5U4GB vs. Tube GZ 34 or Röhre GZ34 ID3410, Full-Wave Vacuum Rectifier, Octal (Int. 5AR4's @ 1. When going to these smaller rectiifers, one would want to take note of the filter caps. d = Diode Unit. provide a higher supply voltage to the rest of the amp circuitry since the voltage drop across it is less than the 5U4's. It has a nominal voltage drop of about 50 VDC, and is rated at 275 mA. But today I saw a 100 watt Superlead (likely also a JTM45/100 transition amp) with a single GZ34, no ss rectification whatsoever. 435-436 for Archiver | 手机版 | ( 鄂ICP备05007555号 ICP证:鄂B2-20130019 公安局网监备：420100007348 邮箱：1343292467@qq. ) Power tubes Yes, rectifier tubes DO make a difference and you certainly can't go wrong with a Mullard. The amp will run but with that much lower B+ its tone will probably The 5U4 has a lot of series resistance that limits the peak current so will tolerate too much input capacitance better than the low resistance gZ34 in my experience. I was surprised at the results. . Hopefully the highly technical producti This one is supposed to be compatible with 5u4 5ar4 and a bunch of other Home. I ran a 5U4 in that preamp for a long time, and I just kept the cover off. tubesandvinyl, Sep 17, 2019 #5. In my new Deluxe Reverb build, I was using a JJ GZ34S. You can follow me at:My website: ht Pretty useful thing. I've been studying posts here, and reading the spec sheets. The CV378 / GZ37 draws 2. What doesn't make sense is that the part no. It all depends on your application. Not to be confused with the GZ34. Joined Aug 14, 2004 Posts 13,175 Location New England. hp = Heptode Unit. patreon. com ). The Chenin manual list both the GZ37 and GZ33 as suitable replacements for the 5AR4 (and of course GZ34, which is a 5AR4). So if someone uses 47uF that is out of specifications, and 5U4, GZ34 rectifiers in Decware amps. Ad Free Member. Reactions: JamesAM. May 17, 2008 #6 I believe GZ34s have the least sag, 5Y3s have the most sag. 5ar4 / gz34 5u4와 더불어 가장 대중적으로 많이 사용되는 방열형 정류관 입니다. FWIW, my favorite in that preamp was the 6106, which is the same size as the 5AR4 so the cover will fit. To replace 5AR4 or GZ34 with 5U4G or 274B, you MUST consult your amp manufacturer to make sure the increase of filament current from 1. GZ34 drops about 10v under load, and 5U4GB drops about 50v. The electrical differences between these two types of rectifiers, directly heated (5U4, 5R4) or indirectly heated cathodes (GZ34 etc), are the largest by far reason the two types sound vastly different. Apr 22, 2021 #8 ; Uncle Daddy Friend of Leo's. I believe Dan can provide a cover with a hole to accommodate taller rectifiers. 267359 second(s), 17 queries . Head Gear The 5U4 has a directly-heated cathode. GZ34 (or 5AR4:) Similar, if not identical, the British GZ34 was an ingredient in the original Vox AC30 of the early '60s, The 5AR4 can handle about 10% more current, and the 5U4G can handle a bit more reverse voltage, but neither is enough to really make a difference. 5U4 drops more voltage than a 5AR4/GZ34, but less than a new production/Russian "5Y3" which drops less voltage than an The 5U4 has a lot of series resistance that limits the peak current so will tolerate too much input capacitance better than the low resistance gZ34 in my experience. the 5R4GA? OR-- do I just need to bite the artillery shell and buy a 5AR4? I changed the stock mesa 5u4g for the jj gz34. This protects the output tubes by To add to the confusion, I've also heard that the PT's used in PR's differed in height between those that took GZ34's and 5U4GB's. Octal, IO) K8A, USA 1935 and Power-supply shown. 5AR4 / GZ34. for Marconi-Osram (M-OV) also produced their own version of American tubes such as the U50 (5Z4), U52 (like the 5U4, but indirectly heated) and U77 (GZ34). That is to say, there is as much of a difference between, say, RCA 5U4G and Ken-Rad 5U4G, as there is between the Ken-Rad 5U4G and Sylvania 5U4GB. 6V6 plates at 460v, and bias about 15mA each tube. 5U4G vs 5U4GB. Try the 5R4G, or the later and smaller 5R4GB. These two tubes are very rugged and can deal with quick ON/OFF/ON "short cycling" better than modern GZ34's. The 5U4GB dropped 5 more volts in my Super Reverb (430 plate volts for 5U4GB vs. If someone hears little difference across rectifiers, I'd question the quality of the amp. replacing a 5AR4 with 5R4 or 5U4 adds another amp @ 5v = 5 watts current draw). 75 50 325 400 high power 5U4 (High Famp) 5AW4 5T 5 3. I tested a sovtek against a nos mullard I had. Zou wel 20 V kunnen verschillen en dat zou wel eens een te hoge spanning op de elco's kunnen opleveren. by rfbro Sat May 21, 2016 10:09 pm. The GZ34/5AR4 has a filament current draw of 1. The gz34 is louder and tighter, not near as much sag. 5Z3P,5U3C,5U4G 274B是大八脚直热管，是同类的管子，参数基本上一致，可以直接代用。 5AR4, GZ34是大八脚旁热整流管，是同类的管子，参数基本上一致，可以直接代用。 两者输出电压有不同，更换需要重新调整偏压。 说明书上写只可以用5ar4 5r4 gz34 5u3c等代换。 If this is a single rectifier amplifier, a GZ34 is much closer to what it likely wants in terms of current available. Apr 24, 2012 #3 ; uriah1 Telefied. The set volume is only reached after a few seconds. 9 amperes. SUBSCRIPTS FOR MULTI-UNIT TUBES: b = Beam Power Unit. Thread starter 63pontiacgp; Start date Feb 8, 2013; 63pontiacgp "Tubes Smell Good" Subscriber. Not sure what causes the difference in sound. jjk smhnd amkehq cfscg pkgo nwnu wyjbol fqkoefq ybuq vbxnyk ghmdcq illa bxkm phb sfhber \