SE cu 300B

[xdanx]

Cica Genalex ar fi cea mai buna raport calitate-pret

https://www.rototubes.com/PX300B-Genalex-Gold-Lion.html

 

 

Genalex Gold Lion PX300B Power Triode

Well built, great sound, nice price

[Italian version here]

Product name: Genalex Gold Lion PX300B Power Triode
Sold by: VKMusic - Canada
Cost: $160. Can. (Currency conversion)
(YMMV)

Reviewer: Roger McCuaig - TNT Canada
Reviewed: December, 2017

Introduction

I am sitting in my listening chair on a rainy Sunday afternoon with fifties jazz recordings playing while I punch away on my laptop. A great job if you can get it. An accomplished designer once told me that the advantage of vacuum tubes is that they are much more linear than solid state devices therefore one can design an amplifier circuit with less feedback, or even no feedback, and the 300B is the most linear power tube suitable for audio applications ever created. This report is supposed to be a review of my new Genalex PX300B tubes but I can't get to that without first talking a bit about my history with this famous tube.

A Brief History

A few years ago I had an opportunity to buy a pair of Canary CA330 monoblock amps. They sounded so much better than the amp that I was using at the time that I couldn’t resist and bought the amps. The traditional opinion that 300B amps had a beautiful mid range but lacked frequency range and detail has gradually given way to an understanding that an amplifier can be designed to eliminate these issues while maintaining the qualities of this amazing tube. At the time of purchase, the Canary amps had a set of Gold Aero tubes in them. I soon discovered that there can be a significant difference in the sound of different 300B tubes. Some can be extremely fast, articulate and detailed to the point of sounding like solid state amps, some have a fat, juicy mid-range and lacking detail and others can be anything in between. I soon upgraded to the TJ Full Music 300B which I found to be significantly better than the Gold Aeros. I would describe them as reasonably fast and detailed with an excellent frequency range and some of the notorious 300B mid-range magic that makes singers voices sound so natural.

Then the problems started, the Canary amps do not have an auto bias circuit so one has to set the bias with a millivoltmeter and a mini screwdriver. Not a big deal except that the tubes/amps wouldn’t hold their bias. I had to readjust it way too often to be considered reasonable. Of course Canary insisted that the problem must be the tubes and not the amps. Well the problem finally resolved itself recently when one of the TJ's failed and I had to put back the Aero Golds. They were much more stable so I guess Canary was right. So why didn’t I try the AG tubes sooner to check the bias stability? I guess its a combination of being lazy and they don’t sound very good.

I really wanted to get something to replace the AG tubes and I finally decided to go with the Genalex PX300B mostly based on the glowing comments that I got from Victor Kung (VK Music) when I was at the Toronto Audio Show. Victor insisted that this was pretty much the best 300B available in its price range and in fact better than some tubes that are significantly more expensive. I should add that VK Music does sell other 300B tubes so it's not like he is pushing a brand because it's the one he sells.

The Search

Now, I can't help but spend some time talking about my discoveries/adventures while shopping for 300B tubes. I should clarify that I started this 300B search with very little knowledge about what was available, other than a few model names. Here are some of the characteristics of the 300B marketplace as I found it: (YMMV)

• 300B models are ephemeral critters. A lot of the documentation and reviews that I found on the internet are for tubes that are no longer on the market. (unless your willing to take a chance on an EBay seller from China)
• There appears to be some re-branding going on. Manufacturers sell tubes willy nilly around the world to other companies as well as to just about anybody who can write a check. I have read and heard stories about tubes being sold through various sources that are basically second grade units that didn’t pass the quality control to be sold out the front door. Of course this could also be people trying to differentiate their offerings when there really isn’t any difference!
• When seeking the origin of a specific tube model I was sometimes left with the impression that I wasn’t getting the whole story. In some cases I just gave up trying.
• There are some wildly different opinions published on the performance and reliability of some models.

What to buy? Who can one trust? In the end I decided that I just had to trust someone so I chose to trust Victor Kung and ordered the Genalex PX300B.

Listening Time

First a bit about the tube. The Genalex is the heaviest of the three tubes I have on hand. It appears to be mostly due to a thicker glass. It has a shouldered bottle whereas the Aero Gold and the TJ are balloon shaped. When powered up a bit of blue halo appears at the shoulder which I have read is normal and nothing to worry about. The internal components are at least as robust as the TJ and more than the Aero. It has a porcelain base and gold plated pins. Both the Aero and the TJ have perforated plates whereas the Genalex has a solid plate. The perforated plates are often called mesh plates however that is in fact something completely different as they are made from a wire mesh and not a perforated plate. The open area in a mesh plate is much greater than in a perforated plate tube. Some writers have attributed specific sound charateristics to mesh/perforated plate 300B tubes however I have far too little experience with tube swapping to comment on this.

So what about the Genalex PX300B? Let's cut to the chase, I am extremely happy with the results. The installation of the Genalex tubes in my system realized some significant and wide ranging improvements. First of all, the wandering bias problem is gone, the bias is dead solid. It hasn’t varied by more than 2% since I set them up. Secondly, I had been plagued with some slight loss of smoothness on loud high notes, especially voices. I had been attributing this problem alternatingly to my preamp or to phono cartridge tracking issues. That’s gone. Also, the very top end of the frequency spectrum has become more natural and the bit of ringing on high piano or vibraphone notes is gone. Milt Jackson is sounding much better.

OK, but what do they sound like? The Genalex tubes are better than the TJ's that they replaced in almost every way possible. The kind of change that makes you want to rediscover your whole record collection. The only exception to the overall performance improvements being the liquid /natural renowned 300B mid-range where the TJ was a bit better. The Genalex excels in speed, timing, accuracy and detail and when these attributes are delivered well this generally bodes well for the sound stage. The performance of the PX300B tubes contributes to making the speakers disappear more as the sound stage deepens and becomes more in focus. The music also has more airiness, punch and presence. The only 300B that I have ever heard that bettered the Genalex with respect to the level of detail it delivers is the very expensive KR tubes. But I found the KR to be not nearly as pleasant an overall listening experience as the Genalex as it is way too analytical for my taste and made my Canary amps sound more like a solid state amp. I should add that I have not tried some of the newer entries into the market from Psvane or Sophia. By the way, the Sophia Royal Princess and the TJ Full Music look identical and I read and article recently from what I believe is a reputable source that quotes Sophia Electric stating that they are made in the same factory but to more stringent performance criteria.

One of the first records up on the table was Neil Young, Harvest. I immediately noted the detail, naturalness and airiness and as the listening progressed I acquired a new appreciation for the excellent production quality of this record. Playing the Rickie Lee Jones eponymous album I discovered little bits of music in the background that I don't recall ever hearing before. These are the kind of things that really lift my spirit and get me binge listening to old favorites and new acquisitions alike.

The most appropriate conclusion I can offer is that I was seriously considering replacing my Canary amps with a pair of new 300B SET monoblocks but that plan has been put on hold at least for a while as these tubes are here to stay.

For the record, I received a reviewer's discount for these tubes. My fundamental motivation for the pursuit of great audio products is for the music. I am solely interested in the best listening experience. I am not a collector, or motivated by high tech gadgets or beautiful components or bragging about how expensive my system is. I just want good music. If the Genalex tubes didn't improve my listening experience they wouldn't stay in my system regardless of the discounts.

My System

Speakers: Coincident Total Victory I; upgraded to Total Victory II by Israel Blume (the creator), and also upgraded with extended feet and modified by me for bi-amping.
Amplifiers: Canary CA330 monoblocks; with NOS rectifier and driver tubes and Genalex PX300B power triodes
Preamplifiers: Doge 8; with 4 NOS 1960s Seimens 12AT7s and 4 pre-war NOS EI 12AX7s.
Digital sources: Arcam CD72 CD player. (used as a transport only) Logitech Squeezebox Music streamer + external Powerwave HA-5 linear power supply. Both of the above devices are connected to a Musical Fidelity X-DAC V3 with matching X-PSU V3 power supply
Analog Sources: Main analog source: Lenco L75 #1: Fully rebuilt; 75 pound plinth, Dynavector DV507 MKII tonearm, Zyx Universe cartridge, Coincident Statement MC step up transformer
Second analog source: Lenco L75 #2: partly rebuilt, original Lenco tonearm, Denon DL160 cartridge, Project phono box SE II.
Interconnects: All interconnnects are DIY cables designed and built by the author with the exception of the MC step up output which is a Tara Labs RSC Vector 1 and the Dynavector phono cable that came with the tonearm.

[Vizitator]

Asa o fi ,uite si niste review-uri (ma rog asta depinde de fiecare) https://blog.thetubestore.com/300b-tubes-review/

[Vizitator viobio]

Genalex este doar brand de vanzare , sunt selecționate si inscriptionate de ei , tuburile sunt fabricate in diverse fabrici rusesti .

Sunt de calitate foarte bună .

https://www.banzaimusic.com/PX300B-Genalex-Gold-Lion-Platinum-Matched.html

http://www.banzaimusic.com/300B-EH-Platinum-Matched.html

https://www.banzaimusic.com/300B-EH-GOLD.html

Parcă seamănă intre ele ....

Editat Ianuarie 16, 2019 de viobio

[xdanx]

IN cele din urma care este concluzia in realizarea unui SE cu 300B pe la 15W. Ce varianta este eficienta si nu enorm de scumpa?

NU are nimeni o schema prin sertar.?

[Vizitator viobio]

Acum 7 ore, xdanx a spus:

IN cele din urma care este concluzia in realizarea unui SE cu 300B pe la 15W. Ce varianta este eficienta si nu enorm de scumpa?

NU are nimeni o schema prin sertar.?

http://www.turneraudio.com.au/Jadis-300B-reformed.html

[Untold]

Cu tuburile in paralel, am citit si eu explicatiile de mai sus si cred ca este dificil...Nu v-ar multumi un 7-8W? Pentru apartament oricum e prea mult...eu ascult muzica pe un amplif de 1,5W si nu-l pot da la maxim...

 

Mai cititi pe aici si mai vedeti si niste scheme:

http://www.single-ended.com/we300bjames.htm

Editat Ianuarie 17, 2019 de Untold

[adrian_pic]

Ar fi fost bine daca initiatorul topicului ar fi spus si ce boxe are.

[xdanx]

Am niste boxe destul de mari cu SPL 90db. Necesita ceva putere. Firma e  T+A Crierion au 40kg bucata.

De asta vreau macar 15w ai aiba amplificatorul. CU PP-ulul care-l am acum de 40w e foarte ok imi zornaie mobila. (o sa-l postez in curand)

Editat Ianuarie 17, 2019 de xdanx

[xdanx]

4 hours ago, Faust2018 said:

http://www.turneraudio.com.au/Jadis-300B-reformed.html

Ca si la prima schema din topic si la schema asta cum rezolvam problema finalelor in paralel . Banuiesc ca trebuie sa fie foarte bine imperecheate

[Vizitator]

De curiozitate care este bugetul alocat pentru amplificator!?

[Vizitator viobio]

Acum 2 ore, xdanx a spus:

Ca si la prima schema din topic si la schema asta cum rezolvam problema finalelor in paralel . Banuiesc ca trebuie sa fie foarte bine imperecheate

Cred că noi doi am stat de vorbă ore întregi la telefon , la un moment dat am abandonat discuțiile telefonice , îți spun ceva din proprie experiență , in tehnică dar și in alte domenii se alege cel mai bun compromis , eu te știu ca fiind un tip care vrea rețeta sau soluția cea mai bună , poate și cea mai putin costisitoare .

Cum spuneam ..... poți face un compromis , vrei putere ? Pui doua 300B in paralel , vrei să fii mai catolic decit Papa  sau habotnic ? Folosești un singur tub 300B , ca fapt divers .....cu un tub obții cam 6... 7w  fără distorsiuni deranjante pentru urechi .  

Un compromis , poate cel mai bun , dacă tot ai bănet de cheltuit , un PP cu 300B , nu te costă cu mult față de un SE cu 300B , ce optii ? O putere de patru ori mai mare decit in SE , dacă la peste 6..7W cu un singur tub 300B SE ampul este aproape de gard cu distorsiunile .....la 7W un PP cu 300B o să fie parfum de trandafiri , este alegerea ta .....nu uita un lucru , in tot ce ti-am spus la telefon  ......am avut dreptate ? PP-ul cu KT88 care il ai ....il ai tot datorită mi-e , pentru ca neavând experiența o luasei pe o cale greșită . PP ....300B....1650R

Încă ceva , capcana in care cad mulți ....schema ....tot din proprie experiență îți spun , pină nu o faci practic nici dracu nu stie cum va suna sau masura in realitate , sunt de parere că nu există om care să vadă un desen si să spuna " sună așa , are bas unsuros sau carnos , vocea sună cristalin , etc " . Eu de astfel de întrebări mă lovesc zilnic  sau aproape zilnic .

Tot legat de schemă , pe net sunt n scheme , multe executate practic , cu masuratori și descriere a sunetului , că să obții ce se descrie acolo ....trebuie să folosești aceleași transformatoare de ieșire cu ce a folosit cel care publică lucrarea .

Dacă totusi o să faci ceva cu 300B , nu te apuca întâi de carcasă , altă greșeală care o fac mulți , tuburile cu încălzire directă sunt foarte pretentioase la circuitul de filamente si masă , faci întâi un montaj pe masă cu asezarea cit mai apropiată de ce vrei să îți iasă pe carcasă , eviți riscul de a asculta permanent un frumos 100hz , care este mare ca volum .

 

 

Succes ! 

Editat Ianuarie 17, 2019 de viobio

[xdanx]

Am stat de vorba la telefon dar nu ore intregi, poate minute intregi si da am abandonat discutiile pentru ca deveneai irascibil subit. Ma rog am trecut peste asta.

PP-ulul actual m-am apucat de el la sfatul tau - ai dreptate-, dar te stresam la telefon ca nu functiona din cauza multor lipsuri pe schema (NFB de la prima lampa, masa de la OPT, rezistentele din anodul celei de a 2 lampa, sunt mai multe - dar s-a rezolvat) , care poate erau evidente dar nu si pentru mine. Am rezolvat-o si pe asta stesandu-i pe multi mai ingaduitori cu incepatorii, nu-i mai insir ca se stiu. AM bibilit la ea am facut  o gramada de modificari (CCS, refacut cablajul de 3 ori)  incat numai am ce sa-i fac 

 

Intrandu-mi in rutina hoby-ul asta as vrea sa fac alt amplificator, dar nu tot PP-ul. De asta as vrea sa fac un SE clasa A si nu de 7w e totusi putin, de asta tot presez pe un 15w macar.

Am citit despre schema Jadis cu 300B postata de tine mai sus - o gramada de informatii - ma doare capu. Incet incet poate gasesc ceva.

Spor la treaba Viorel

[Vizitator viobio]

Acum 19 minute, xdanx a spus:

Am stat de vorba la telefon dar nu ore intregi, poate minute intregi si da am abandonat discutiile pentru ca deveneai irascibil subit. Ma rog am trecut peste asta.

PP-ulul actual m-am apucat de el la sfatul tau - ai dreptate-, dar te stresam la telefon ca nu functiona din cauza multor lipsuri pe schema (NFB de la prima lampa, masa de la OPT, rezistentele din anodul celei de a 2 lampa, sunt mai multe - dar s-a rezolvat) , care poate erau evidente dar nu si pentru mine. Am rezolvat-o si pe asta stesandu-i pe multi mai ingaduitori cu incepatorii, nu-i mai insir ca se stiu. AM bibilit la ea am facut  o gramada de modificari (CCS, refacut cablajul de 3 ori)  incat numai am ce sa-i fac 

 

Intrandu-mi in rutina hoby-ul asta as vrea sa fac alt amplificator, dar nu tot PP-ul. De asta as vrea sa fac un SE clasa A si nu de 7w e totusi putin, de asta tot presez pe un 15w macar.

Am citit despre schema Jadis cu 300B postata de tine mai sus - o gramada de informatii - ma doare capu. Incet incet poate gasesc ceva.

Spor la treaba Viorel

Minutele adunate au fost ore .

[Vizitator viobio]

"7w e totusi putin, de asta tot presez pe un 15w macar." 

211,845,805,OT100 .

Editat Ianuarie 17, 2019 de viobio

[Vizitator]

211