Tube Rolling: Does it Make a Difference?

[watchnerd]

.The biggest joke is the EH tubes with gold pins that are 3x the ones with normal pins and are the same in every other way. Yeah that micron thick 8mm long gold plate is going to be transformative over the meters of copper trace and solder on the circuit. Lol.

You're not paying for the gold as a sonic enhancer.

You're (supposed to be) paying for tubes that are graded better, with tighter tolerances to spec.

The gold is just a way to add a little cache and tell the difference on the more premium product. Oxidation resistance, also, as it is on gold-plated RCAs.

This is somewhat true for non-mil-spec NOS tubes, as well.

All the E188C tubes NOS I have, none of which are current production (nobody makes this grade anymore) are gold pinned.

They're from the likes of Siemens in the 1960s, from back in the day when tube tolerances mattered.

 

[imagidominc]

Amir: "I would not waste time rolling tubes."
The subjectivist audiophile community: "So you have chosen violence."

 

[DualTriode]

Hello All,

The biggest things that you will measure in tubes are noise and distortion.

Where you may see tube FR changes is where the higher tube amp output impedance interacts with variable load impedance. Think speaker loads or headphone loads.

The noise can come from the tube and or the amplifier circuit. Tubes and tube circuits can have noise caused by relatively large voltage drops across resistors and from the tube it's self. Replace the old school carbon compound resistors with lower noise metal film resistors for a good start.

A few thoughts.

Thanks DT

I am speaking of measurable stuff nothing subjective.

 

[DualTriode]

But the harmonics are very different look at the h3 and h4, and the shape of high frequency harmonics, there are several dBs' difference.
The distributing of harmonics is the key of the tone color of instruments.

Hello,

You are partly correct as long as those higher HD's are above the noise floor.

Remember that large sample size and averaging allows the the FFT to hide the random noise in the noise floor in the frequency domain.

In the real "time domain" the noise floor masks the low magnitude higher Harmonic Distortions.

The low magnitude higher distortions just become part of the hiss.

Thanks DT

 

[DanielT]

They should be silicone and not regular rubber if they're to be used on power tubes.
So... I mean... the idea is to damp internal vibration (root cause of "microphonics") of the tube's -- shall we say -- infrastructure, which certainly can be audible. Do they really 'add value'? Beats me. I don't use any and never particularly felt motivated to.

Tubes get hot! It's best to have a ring with a suitable material. It is discussed in this video below, among other things.
9:50 into the video regarding tube dampers.

I think you can have tubes in your secondary system. That if the wallet allows. It's fun with variety. In the main system you can have some good modern speakers and amplifiers, something that Amir top tested. In the secondary system something vintage. For example:

Amir:
I love the simplicity of tube amps like this. There is just so little to them. If I were less busy, I would not mind playing with one to get it to optimal performance.

Review and Measurements of Dynaco ST 70

This is a review and detailed measurements of the vintage Dynakit Dynaco Stereo 70. It is on kind loan from a member who bought it used online and repaired it. Previous owner hand upgraded it but could not get it working. Given that it is 60 years old, one can forgive the rust and dust...

audiosciencereview.com

 

[beefkabob]

I never understand why it's called "rolling tubes" as opposed to "changing tubes". It seems to imply some inherent skill involved in the process.

Because when you set them on the table, they roll and fall to the floor? Because you're rolling the dice when you buy this garbage, and always coming up snake eyes?

 

[GeekyBastard]

You do not “roll” tubes in and out of their sockets. If that would even be possible, it would severely bend the pins. Instead, you pull them up and straight out, and insert them straight in. You might have to rock them back and forth a little to loosen them, but you do not roll them.

That's what the article said, take it with a grain of salt.

 

[Kegemusha]

Did they deny to make any measurements? Magic brand.

I was thinking the same on the Hegel reviewed here last week, I dont get it. This is just pure nonsense.

 

[DanielT]

Forget to roll tubes. If you want to roll, you should do so with girls in the hayloft.

Amir, nothing you need to test and report the results. We know how it works. He he.

 

[Poultrygeist]

I bought a SET amp that came with Chinese 6n3 preamp tubes. I was not happy with the sound so I called the seller to see if I could return the amp. He said before you return it substitute WE396's for the 6n3's. I did and was floored by the improvement. The change was so drastic I kept the amp.

Tubes can make a huge difference if replacing poor quality tubes with better ones.

 

[Emulator II]

The remaining 10 tubes (5 pairs) are pretty easy, because they're either noisier, more microphonic, or have noticeably less gain.

I can just put on headphones with nothing playing, crank up the volume, and listen for noise and microphonics

I use a Dynavox TPR-3 tube preamp in my system which uses a pair of the same type of tubes Amir tested. While I'm not sure about sound differences regarding "tube rolling" the differences in noise and especially microphonics are huge. The unit came with current chinese tubes (6N3) which were ok in this regard.

Then I followed some recommendations in the net and changed the tubes to the GE 5670 (for better sound ;-) ) and the microphonics became unbearable. The Teslas I've tried were a little bit better and the Philips tubes were pretty ok.

I ended up with some cheap NOS russian military type tubes (6Н3П-ЕВ) and couldn' t detect any (audible) microphonics at all. Audible noise is pretty low too. So I sticked with them and quit "tube rolling".

 

[watchnerd]

I use a Dynavox TPR-3 tube preamp in my system which uses a pair of the same type of tubes Amir tested. While I'm not sure about sound differences regarding "tube rolling" the differences in noise and especially microphonics are huge. The unit came with current chinese tubes (6N3) which were ok in this regard.

Then I followed some recommendations in the net and changed the tubes to the GE 5670 (for better sound ;-) ) and the microphonics became unbearable. The Teslas I've tried were a little bit better and the Philips tubes were pretty ok.

I ended up with some cheap NOS russian military type tubes (6Н3П-ЕВ) and couldn' t detect any (audible) microphonics at all. Audible noise is pretty low too. So I sticked with them and quit "tube rolling".

Similar experiences.

Some (but not all) of my "recommended for the sound" tubes are my noisiest, most microphonic, or low gain.

My Communist block mil-spec tubes from Reflektor (6H23P-EB), Tesla (E88CC), and Tungsram (E88CC) are all quiet, as are my Amperex, Mullard, National, Philips, Siemens, Sylvania JAN, Telefunken, and Toshiba.

I bought extra pairs of the Reflektor, Tesla, Tungsram, and National tubes because they're cheaper than the audiophile faves, but robustly built and quiet.

My dark horse low noise, low microphony tube is from BEL, from India.

All my Shuguang tubes have been noisy and microphonic, but to be fair, they were freebies that came with gear. I've never bought one of the upscale re-brands from Psvane or similar.

 

[mhardy6647]

Tubes get hot! It's best to have a ring with a suitable material. It is discussed in this video below, among other things.
9:50 into the video regarding tube dampers.

Well... yes and no. Power tubes in a typical circuit and HV rectum fryers rectifiers, with high levels of plate dissipation, do get oven hot.
Small signal tubes get pretty warm but can (kids don't try this at home) in many cases even be hot-swapped. Note, I am not sayin' that's a best practice; I'm just sayin'.

 

[watchnerd]

Well... yes and no. Power tubes in a typical circuit and HV rectum fryers rectifiers, with high levels of plate dissipation, do get oven hot.
Small signal tubes get pretty warm but can (kids don't try this at home) in many cases even be hot-swapped. Note, I am not sayin' that's a best practice; I'm just sayin'.

Some of my 6922s (but not all) in a headphone amp can get hot enough that I don't want to touch them for hot swapping.

This is less true now that I have them on socket savers, lifting them up out of the case more and thus running cooler.

 

[magicscreen]

Because when you set them on the table, they roll and fall to the floor?

Yes, unfortunately this happened to me. But it fell onto a very soft carpet.
I changed a new chinese tube to an old russian one. Very much better sound for me. So tube rolling is fun.

 

[symphara]

The only glass tube rolling I recommend is Coopers Sparkling Ale.

Roll enough of those and your distortion will go through the roof!

 

[Spkrdctr]

I'm old enough to remember when every store that sold TV's and radios even some corner drugstores (in NYC) had large floorstanding tube testers. You would run the testers yourself. Customers would come in with a shoebox full of tubes and test them. A waste bin was kept next to the machine for bad tubes. No one would even think of "tube rolling". Tubes were either in the "green" ranges or they were thrown away.

I would never want to go back to those days.

Oh, I'd go back. That was FUN! Tube testers were giant toys for kids with some tubes to check for Dad.

 

[watchnerd]

Oh, I'd go back. That was FUN! Tube testers were giant toys for kids with some tubes to check for Dad.

I remember when I was a little little kid (4-5?) the drug store, that also had ice cream cones, had a tube tester.

But by the time I was 8-10 years old, it was definitely gone.

 

[levimax]

I'm old enough to remember when every store that sold TV's and radios even some corner drugstores (in NYC) had large floorstanding tube testers. You would run the testers yourself. Customers would come in with a shoebox full of tubes and test them. A waste bin was kept next to the machine for bad tubes. No one would even think of "tube rolling". Tubes were either in the "green" ranges or they were thrown away.

I would never want to go back to those days.

Yea much better these days.... if an electrical device doesn't work you just throw the whole thing away.

 

[watchnerd]

Yea much better these days.... if an electrical device doesn't work you just throw the whole thing away.

There was probably less e-waste in the old days.

Things might have been more sustainable, although tube manufacturing is pretty bad for worker health.