What made you change to a 6SN7 preamp?

Andy @ Vintage Tube Services is a great guy and helped me decide on the best 6SN7 for my monoblocks.   Question-I have not had microphonic tubes in 50 years of audio gear.  For the past 20+ years, my pre-amp and phono stage uses subminatures which have a reported life of 100,000 hours, really thick (bomb use) glass and great sound.   Can using various dampening rings such as Herbie's reduce or eliminate most microphonics?   Or is the microphonic the result of internal parts vibrations?  

For you 6SN7 fans, the VT231 equivalents can be a fun roll especially for rockers. IIRC, the Kenrads were a relative bargain when I tried them. Cheers,

Spencer

It was said that Vintage Tube carefully tests all tubes for microphonics.

Testing equipment has no way to do this.

The only way is to plug the tube into your component and wait a bit.

True, but the dealer can listen to the tube using a high gain device like a phono preamp. This is what Kevin Deal uses. But this type of test only insures that the tube is non microphonic when it leaves the dealer.

Can using various dampening rings such as Herbie's reduce or eliminate most microphonics?   Or is the microphonic the result of internal parts vibrations?  

@fleschler ,

IME, Herbies can reduce microphonics up to a point. Once a tube has gone full-on microphonic nothing can help. Tube dampers lightly touch the glass envelope and reduce resonances, but in many cases the sound will be affected. It may make the bass tighter in a good way or it may reduce the liveliness of said tube, making it sound dull.

It was said that Vintage Tube carefully tests all tubes for microphonics.

Testing equipment has no way to do this.

The only way is to plug the tube into your component and wait a bit.

Tube sellers cannot do this. Hoarders may have the best tubes. But even then, you need to buy more than you need just in case.

I paid $750 for 4 Psvane 6SN7 Globes and they were all microphonic.

Vintage tube service tests them in circuit, he has many different components to test them in.

@invalid I paid $750 for 4 Psvane 6SN7 Globes and they were all microphonic.

$750 for a quad - where did you source them from? That’s interesting, you can buy a quad of PSVANE Cosor version globes for $259/quad. Can you share more...

It’s helpful to trace this back. FYI: info through an overseas distributor I learned of others having problems here in the USA with (some batches) of tubes that were packed properly (originally) coming from the Shenzhen factories. Then, arriving to some dealers, being unboxed from large lot boxes, then repackaged and packed loosely without cotton in smaller and less protective boxes. And, more subject to vibration and shipping damage to the buyers. Good tubes gone bad in reseller packing and shipping trying to save weight and shipping costs. Argh. It took TJFM and GDParts two years to figure this out and what was going on. Since then, I’ve been only buying the premium boxed pairs distributor-direct, and they come in their own individual foam insulated jewelry type boxes. Not in the individual cheap thin paper boxes loosely packed by dealer-resellers.

Ask the tube dealer reseller before they ship, how they are packed!  

Wondering how yours arrived, and for $750 sure seems questionable.

Decooney you have to ask Mglik about the quad of psvane tubes I was just quoting his post about vintage tube service.

@invalid  ok, did not see it as a quote. Will try again, Thx.  

@mglik same question, above. And did the tube reseller offer you a return, refund?

Ralph @atmasphere was my primary reasoning to try the 6SN7. No one is kinder, smarter and with incredible patience.  However, he hasn't been able to talk me into his class D AMPS yet.......

A week or two ago someone posted about removing the PreAmp from your system and go direct from the DAC . I tried for a week . It was clean, clear and had Dynamics  but........lacked  engagement . I of course but the pre back in the system yesterday . 

Ralph's UV-1 preamp gave me my first taste of 6SN7's. That small simple circuit produced a huge soundstage, music with weight, and layering of textures. I've moved on to another 6SN preamp and an Atma-sphere S-30 which uses (6) 6SN7 input tubes.

Vintage tube service tests them in circuit, he has many different components to test them in.

@invalid , thanks for posting this. Andy has pics of all his testing gear on the website. Many years of purchases and I've never had a microphonic tube. Also the lowest noise of all my tube purchases. 

I did not jump to a 6SN7 preamp for the tube but did so to upgrade at preamp and the one I picked happened to use 8 of them including headphone amp.  

It also uses a tube rectifier which also contributes to the sound as well as a resin encased R-core power supply transformer.  

I came from a 12AU7 based preamp (4 mu followers) and I never loved the sound despite lots of tube rolling.  I have several on hand from prior amps and preamps.  

The sound of the new preamp with stock EH 6SN7 was better than the outgoing preamp by a wide margin.  Much larger soundstage, a purer more refined sound that was more transparent and bassier at the same time.  

After several NOS tube and rectifier trials the overall presentation is just incredible.  

Lots of variables in the comparison but the 6SN7 tubes are part of the mix that got me here.  

Andy will guarantee there are as new and work , return I don’t think so

Brent Jesse has a return to fit your audio for 30 days plus you can take out up to 2 year insurance with  Brent if a tube fails for little money 

What Is Your 100% Money Back Satisfaction Guarantee? Individual service and customer satisfaction is paramount to VTS. Every tube purchase is backed by my guarantee. If for any reason you don't like the tubes, you can return them within 20 days of receiving them with generous exception if notice is given. Tubes are guaranteed 90 days against manufacturing defects with the exception of 6DJ8 type moving coil phono input tubes and certain rare models that simply chew up tubes.

What Is Your Return Policy? A decent sized square box of at least the size they were sent in is proper. Any tubes returned in padded envelopes or "little flat-ass" (video tape sized) boxes will be returned to sender and charged accordingly.

Thanks @audioman58, I should have just went to the Vintage Tube Services website.