tube vibration control

[christensenleif@msn.com]

hello
when it comes to vibration control, most people are so focused on the platforms
and when it comes to tube gear, all sorts of dampers mounted on the glass of the tube
however the glass itself is not the main concern when it comes to tube vibrations, but rather the interior of the tubes
especially the filament wires
I have an all out LCR riaa built i 2004(constantly upgraded though)...really nice unit with a onboard TVC(now AVC)
the problem arose when I installed a remotecontrol kit from Jon Chapman/Bent Audio in Vancouver
I chose the option with Seiden switches and dual stepper motors to match the contact points of the Seiden:
once the motors started moving the switches the E810F tubes picked up the vibrations and amplified the mechanical impact on the tubes
after a lot of research I discovered Allnic Absorb Gel tube bases and once installed, problem gone
a few years later I started to try and locate some more, but it turns out Allnic don´t sell to external users anymore, but keep them to their own gear....
have been looking for years now for some replacements when I stumbled over a picture of an Aeries Riaa
and lo and behold! what did I spot....
ha ha turns out the Allnic absorb gels are based on a British product from the 60s.....
yesterday I found a US source and ordered some......
here it is and your welcome to try yourself

Plug Play NOVIB Socket Saver©-1960s NOS British McMurdo Phenolic socke

Top part is Brand New 1960s British Made McMurdo Phenolic socket. Anti-vibration Base* has silicone to reduce microphonics. Tube pins are exact size of a typical NOS Philips tube for snug fit, unlike cheap Chinese bases with thinner pins that wobble in the sockets. Engineered in-house and...

pulsetubestore.com

 

[Aries Cerat]

We now make our own vibration sockets since 2017, we measure 40db mic noise reduction. The ones in picture were only about 10-15db max.

Cheers
S

 

[christensenleif@msn.com]

The new ones are enclosed in metal jacket?
You offer for public?
Best
Leif

 

[Aries Cerat]

You are right on the money, vibrations on tubes are transferred though pins.
Footers and racks are all nice, but cutting vibrations right on the pins is many scales of magnitude more efficient.

Unfortunately we do not have time for now to make them as separate product, we offer them standard in our phono stages, and some preamps as option.Maybe in the future.

Below is the testing when we developed them. Device under test: PCB with tube circuit, installed inside heavy chassis. Chassis under excitement using "brutal" broadband exciter/vibrator. Results is direct output of the tube output, with (yellow) and without(gree) our isolation socket installed to the tube.

Of course in our tests, the "excitement" signal is many magnitudes higher than vibrations in a listening room, but it is a good tool to see what works and how to best tackle vibration pick up.

Cheers
S

 

[cal3713]

I need one of these, but for a 4 pin 2a3-type socket. Has anyone seen a source?

I saw allnic used to sell them to the public, but now like AC they're just proprietary.

 

[cal3713]

I've got a custom made dht preamp (pictured in my profile) and have looked into modifying the sockets to float them as mayer does on his products, but it looks like I'll probably do quite a bit of damage to my baseplate in the attempt.

 

[mtemur]

For tube vibration control Shun Mook and Herbie offer great products IMO/IME






I no longer prefer to use any of them but they certainly alter the sound.

 

[christensenleif@msn.com]

still just glass and filaments will continue to move from socket born vibrations

 

[Kingrex]

Floating the transformers is also effective. That is the source of most vibration. Also, floating the mounting plate the tube sockets are attached to helps.

 

[Aries Cerat]

still just glass and filaments will continue to move from socket born vibrations

100% on the money. From tests, in most tubes, >95% of the vibration is not transmitted from glass but from pins.

 

[christensenleif@msn.com]

I had made some brass rings at about 100g each that mass loaded the tube and it helped a little because I changed the transmission resonance from the socket, but not anything like the Absorb-Gel

 

[Aries Cerat]

I had made some brass rings at about 100g each that mass loaded the tube and it helped a little because I changed the transmission resonance from the socket, but not anything like the Absorb-Gel

Yeap. We measured 40db reduction in some freq on our solution. You are spot on, the game is to isolate the pins.
With on-glass solutions, mainly you change the distribution of the vibrations.

Cheers

 

[microstrip]

100% on the money. From tests, in most tubes, >95% of the vibration is not transmitted from glass but from pins.

Yes. It is why some manufacturers isolate the small section of circuit handling tubes with vibration insulators and connect them using flexible wires.

 

[DasguteOhr]

Thomas Mayer have phantastic solution to isolate tubsockets from housing.
especially with steep triodes which are often sensitive to microphony.
is of course more difficult to implement afterwards.

Making of a D3a LCR Phono Preamplifier

Hi! Here some photos of a recently finished phono stage and it's construction process. This time the color scheme is black / gold. As all m...

vinylsavor.blogspot.com

 

[bonzo75]

Thomas Mayer have phantastic solution to isolate tubsockets from housing.
especially with steep triodes which are often sensitive to microphony.
is of course more difficult to implement afterwards.

Making of a D3a LCR Phono Preamplifier

Hi! Here some photos of a recently finished phono stage and it's construction process. This time the color scheme is black / gold. As all m...

vinylsavor.blogspot.com

D3a is a pentode not a triode. Though can be triode connected. TM does not make DHT phonos but indirectly heated tubes.

 

[cal3713]

Thomas Mayer have phantastic solution to isolate tubsockets from housing.
especially with steep triodes which are often sensitive to microphony.
is of course more difficult to implement afterwards.

Making of a D3a LCR Phono Preamplifier

Hi! Here some photos of a recently finished phono stage and it's construction process. This time the color scheme is black / gold. As all m...

vinylsavor.blogspot.com

I would love to implement this, but unfortuntely cutting my top plate (it's pictured there in my profile image) just isn't in the cards.

 

[cal3713]

And I agree with all the posts. Vibration dampening of the glass helps, but it's clear that there's also noise coming from the chassis. It is audibly airborn and speaker created.

 

[cal3713]

Yes. It is why some manufacturers isolate the small section of circuit handling tubes with vibration insulators and connect them using flexible wires.

Yes, exactly, this is the solution I'm after. Unfortunately it looks like I'll have to manufacture my own.

 

[Blue58]

Herbie’s audio lab used to sell washers suitable for tube amps as I used them between all transformers and tube sockets to isolate them from the chassis.
I could only see the grungebuster washers currently on their site but an email may identify the older version(black ones).
https://herbiesaudiolab.com/products/grungebuster-washers?variant=12693388066871

Hope this helps.

Just remembered it was called dBNeutralizer

 

[microstrip]

Yes, exactly, this is the solution I'm after. Unfortunately it looks like I'll have to manufacture my own.

We have to look for the Allnic Absorb Gel Vaccum tube dampers in the audio marketplace sites - they show from time to time.