How much do rectifier tubes influence the sound of your amplifier? I have Mono blocs that I enjoy, but though the designated writings says 5u4GB by Sylvania they are different size, but similar shape.
If it is used in a Guitar amp it effects the sound quite a bit.
OTOH, if the filter section of the PS is properly designed, in a Class A amp the effect should be almost nothing,
An LC filer section forms an effective barrier between the amplifier & the raw power part of the amp. That is what the filter is meant for.
Audiophiles prefer tubes like the 5U4 a lot because they look impressive. But appearance doesn't make a rectifier.
There are better tube rectifiers, the 5U4 is simply the archaic 5Z3 on an octal base. Right out of the early 30s.
GZ34 & 5V4 are better as far as regulation is concerned. But they don't look as impressive.
So bottom line, really depends on what the objective is, an Object of Art and / or something to listen to,
Just pull out some vinyl jazz or Mozart, pour a glass of good wein & enjoy. 👍
I am not clear. What are you thinking here? You have a diff rect tube on each amp? Are you trying to replace them and with what? 5u4 draws 3A filament current and drops more volts than gz34 or 5AR4. So one should be careful with swapping rect tubes as B+ & working points may change. Actually I found differences in voltages even between brands of the same rectifier. On the basis of that alone I would say you should have the same brand and type to try to have the same B+ on the monoblocks and make sure that the voltages are what you want.
Certainly going from 5U4 to GZ34 may change your B+ by a significan amount.
Certainly going from 5U4 to GZ34 may change your B+ by a significan amount.
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Kingfisher asked about the sound, not the results in circuit.
All the more reason the go SS rectifier from the start. All my experimental amps used SS rectifiers.
But in one project I did use a 5AR4 to demo power frequency effects in rectified voltage
caused by difference in the resistance of the halves of the HV secondary of a CT rectifier system, 🙂
Wow, didn't intend to step in a pile... it's just that my tech. is strictly voltage oriented and when it isn't broke he will not fix it...lol My concern was the sound. I actually have one bastard el34 in with the mix. I swapped channels from source and listened, couldn't tell a difference. So I only wanted to know about the sound of what probably is similar tube of different year. Both read 5u4GB.
I don't know much but when I swapped the new Shuguang rectifier tube in my non-diy 300B SE with an old U.S. one, the bass improved significantly. However, the whole amp seemed to run much hotter to the touch so I eventually switched back.
This is nothing. On many forums, tube rectifier "sound" debate will rage on for several pages. 🙂
What amp do you have?
jeff
kingfisher continue to enjoy your amps......but always have a set of spare valves from a good known source.
BTW I like your tech.
BTW I like your tech.
Thank you for your replies, tube rolling is not within my budget and since the overwhelming consensus points to "NO" for rectifier influences of sound, I'll close this conversation.
BTW, my amps are a pair of upgraded Heathkit W4-AM Wired to accept El34 tubes. I discovered one amp at a place that markets used clothing, housewares, sports gear...ect. set in a wood cabinet resembling a phones setty I purchased for a few dollars. The other purchased online by my fiance... she's a keeper.😉
As has been mentioned.... it can make a big difference in a guitar amp. More difference the further the amp runs from class A: the supply sags more as current draw increases (i.e., as you play), which gives a touch of compression: subtle, but lovely.
Not experienced enough with it in hifi stuff to comment. But my guess would be for a non-class A output, you'd want a stiffer supply there and it would be built accordingly, which sounds like a SS rectifier to me. But it is just that: a guess.
Cheers, and regards,
Ant
Not experienced enough with it in hifi stuff to comment. But my guess would be for a non-class A output, you'd want a stiffer supply there and it would be built accordingly, which sounds like a SS rectifier to me. But it is just that: a guess.
Cheers, and regards,
Ant
I can certainly give you a little information on this. I just did a shootout of several rectifiers from my own collection. These included Sylvania VT244, and some other 5U4 types like Svetlana and a Chinese metal base one. The best was a GE 5U4GB, better than an RCA version and two or three other 5U4GBs including Philips which were all good as well. However, I did also like the Mullard GZ33 and even better were the Cossor 53KUs, the fat bulb better than the tall skinny one. My eventual favourite by a micro margin was an RCA Jan 5V4G over the GE 5U4GB, but that has a maximum current of 175mA so probably too wimpy for you. My amp is a SE EL12n in triode with a 26 driver in filament bias.
Hey JH,
I was talking to the OP and I simply mentioned a statement of fact about different tube rectifiers that I thought was important and may escape the casual tube roller. That included myself before I started to play with tube circuits and measuring and observing the turn on characteristics of several tube rectifiers.
Best,
p
No 'piles' here. I was trying to understand your question.
Peace
Changes were subtle - you don't get night and day changes from rectifiers. The ones I preferred had slightly cleaner high frequencies and a little more space around instruments and voices. As I say subtle, and only perceptible because I use test tracks that I know extremely well from years of using them. My test tracks are opera and jazz piano trio and vocals, which includes the drumkit. I listen particularly for the tonality and timbre of acoustic instruments.
I have not tried SS rectification with tubes. I have to say my favorite part of tube rectification is the automatic slow turn on out of the 5ar4/gz34. I use the trick of the 2x UF4007 diodes to have better switch off performance and be able to charge a larger smoothing cap with no issues.
Is this a modification you observed on another forum and did yourself? Did you change anything else besides the EL34s?
To answer your question, the 5U4 is probably the least variable rectifier, IMO. Having two that are slightly different is having very little effect on the sound. What's more important here is the voltage drop of different kinds of rectifiers. The 5U4 should work fine with the W-4 but a 5V4 is what the original called for and will provide a bit more B+ than the 5U4.
Hello grovergardner, "Is this a modification you observed on another forum and did yourself? Did you change anything else besides the EL34s?"
I followed on audiokarma.org soon after acquiring the pair. The side featured a very good break down of the power supply upgrades as well as the mods to allow el34s. Not having the confidence to delve into I turned it over to my repair guy who followed the schematic as posted on the site.
I followed on audiokarma.org soon after acquiring the pair. The side featured a very good break down of the power supply upgrades as well as the mods to allow el34s. Not having the confidence to delve into I turned it over to my repair guy who followed the schematic as posted on the site.