Pass XP-20 DB-25 Umbilical upgrade: Has anyone any suggestions on how much of a difference and what brand?

Just ordered two Tubulus Argentus DB-25 V2 umbilicals for my two Pass XP-25. Can't wait to get them and see for myself what they are doing compared to the stock "printer" cables that come with the phono amps.
J, if your experience is mine, prepare to have to sit down LOL. Tubulus DB25 upgrades have been a seminal moment in my system evolution.
Well, let's see... :)

But the experience will have to wait a moment longer as the lead time for production and shipping is currently 3-4 weeks.
J, Aldwin of Tubulus is a total delight to deal with, he offers a very generous 30 day No Quibble sale/return, longer if needed, A+ service and quality of product.

For me, noise is the enemy. My loom of Sablon cables, Oyaide dedicated lines and Entreq grounding, have taken my previous noise floor right down, revealing layers of musical info I didn't even know existed.

I had no specific expectations for the Tubulus, but it's eliminated another level of grunge (my Nat amps really aren't that quiet), and the effects have been startling, no exaggeration.

I wish you luck that you get my level of uptick. It should be worth the wait.
Finally received two Tubulus Argentus DB-25 V2 umbilicals yesterday. Might take another week though before I will find the time to actually try them out. So far I can say that the build quality is excellent.

J, this was one upgrade I had close to zero expectations on, yet got on w installing them the moment they arrived.

They've become a major bridge to my final sound, and totally confounded those low expectations.
Today I finally found the time to do some critical listening and do the comparison between the Pass stock 'printer cable' and the Tubulus Argentus DB-25 umbilical. The positive side of me taking so long to finally finding the time was that in the mean time the Tubulus was already installed and cooking, and therefore now already has seen some 160 hours of burning in.

To be honest, I was rather surprised how clear the differnce was.

Despite what Marc wrote about the Tubulus Argentus and what it did in his system I started the comparison with my usual rather low expectation level in regard to cables. I did have the occasional pleasant surprise in the past, but generally speaking my system is somewhat insensitive when it comes to cable changes.

Well, not this time. The improvement, especially in regard to soundstaging and imaging, was very obvious. There was considerably more air between instruments and the soundstage was noticably bigger. Also detail retrieval improved, if not on the same scale like what happened in regard to imaging.

This cable is a clear winner in my system as umbilical for the Pass XP-25 and will definitely stay. Add to this the really good communication and service from Aldwin of Tubulus and I must say that I can recommend this to all Pass users wholeheartedly.
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I told ya, buddy.

Re low expectation bias, you and me. Indeed, this was something of an afterthought for me, only swung by Aldwin's sale or return.

For me, this is one of three recent changes that have transformed my sound.

I'm v pleased J that you're hearing so much of what I am.
Yes, it's definitely a worthwhile improvement - although it sounds as if the impact in your system is even bigger than in mine.

It just leaves me wondering why Pass is/was selling their amps with such an inferior stock umbilical. Especially since there are only very few aftermarket options available to improve the stock cable. Heck, I mean, until recently I only new of one, the fairly overpriced Revelation Audio Labs umbilical.
J, I guess its like everything in audio, designers prioritise some things over others.

Peter Lederman is one of the all time greats in analog. But you cannot convince him that the stock DC wall warts he uses w the Straingauge cart energiser can be improved on.

Er, they can. Big time. I know, I've spent big on a bespoke psu. And the Pass, and my Nats, can be majorly impvd w these Tubulus DB25's. Just don't tell the designers.
Ordered a second set of Tubulus Argentus DB-25 umbilicals today to also get the Pass XP-30 equipped. Let's see what the cable does there.
Meanwhile the second set of Tubulus Argentus DB-25 umbilicals for my Pass XP-30 arrived. Installed them last night but only had the time for a very brief listening session afterwards. The first Impression is very favourable. More listening unfortunately only on the coming weekend.

The cables are rather stiff and heavy so Installation is a bit of a pain if the room behind the rack is limited. Also, they pull quite heavily on the receptacles. I supported the DB-25 plugs with a small block of Sylomer each which helped a lot.
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"Good things come to those who wait".
J, if noise is the enemy, then the Tubulus DB25 is one of the greatest warriors of all time.

I'm very interested in your feedback on the Tubulus cables on the XP-30. I've had my (stock cabled) XP-30 for about 5 years. I respect the feedback from the XP-20 owners who say they heard noticeable improvement with upgrade umbilicals.
I have read the XP-30 music signal never leaves each monoblock. I believe the umbilical carries power and controls volume on each channel's monoblock.
If this is accurate, there should not be a change in sound with a different umbilical.


To put my interest into perspective, I will document my experience with umbilical cables.
I lived 3 houses east of a canal in Scottsdale, for 21 years. On the canal road, there are also high tension electrical lines.
In July, you can hear these lines crackling from peak demand. I commented on this, talking with my neighbor one evening. He grabbed a 48" fluorescent bulb, and we walked over to the canal, directly under the power lines. He held the bulb in one hand and it glowed. I was surprised!
I was using a Pass Aleph P preamp. I upgraded to the Pass X1 with the full size separate power supply.
My equipment rack was full, when I had the Aleph P. I installed the X1 control chassis in my rack, with the power supply on the floor. the umbilical was stretched almost completely.
My system was noisy! I believe the umbilical was picking up the noise from the high tension lines. I re-arranged the X1 with the power supply directly below the control chassis, the problem was eliminated.
I'm sure there are other scenarios where RF, etc. can come into play. This was my experience.
I bought my XP-30 after I moved. I live in Tempe now, all utility lines in my neighborhood are buried. My system noise floor is dead quiet.
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I'm currently travelling and only saw your post just now. That's quite some story with the lightbulb. My first thought actually was whether this wouldn't also have an impact on the human body, at least long term?

Anyway, it's difficult to comment on mains quality in Arizona vs. ours over here in Germany and what impact this has on a system's sound quality respectively. What I can say is that in my system the difference between the stock printer cable vs. the Tubulus Argentus DB-25 was quite noticable. With the XP-30 it's basically the same effect like the one I described a few posts up in regard to the XP-25, just with a slightly lesser impact for the line stage vs. the phono stage.

In the end I see this like replacing a component's cheap stock mains cable with a better aftermarket one. Only that here we are talking sending power that has already gone through the power supply over a connection that I believe to be more sensitive.

I would recommend to contact Aldwin of Tubulus and discuss his return policy for sales in the US and try it for yourself. And I would be most interested to read about your experience.

Thanks to Marc for recommending the Tubulus directly to me as well. It has just 24hours in my modified XP-25 setup, and it is extra-ordinary indeed. The increase in clarity, timbral accuracy and articulation cannot be overstated. Deep and very articulate bass definition; dynamic explosiveness. A TOTAL AND UNEQUIVOCAL NO-BRAINER especially for the price.

Thanks Marc again!
Ack, my pleasure. This was one upgrade I had no feel I really needed. Esp since my stock DB-25 was already a Siemens special order. But Aldwyn's enthusiam and non hard sell attitude won me over. And like you Ack, the Tubulus worked straight out of the box in all the ways you described.

If my Nats amps have one drawback, it's their higher than ideal noise floor, and the Tubulus DB-25 has made great strides in reducing grunge, but not at the risk of less musicality.
Is Revelation Audio the supplier of the umbilical cord cable to Pass for their new XP-22 / 32 / 27?
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Received the 1m Tubulus Argentus DB-25 umbilical cord 6 months ago.

I was hesitant to put it in straight away, after feeling its added weight, and finding out there's some shielding around the conductors, thinking it's most likely going to add a veil or colour the sound in some ways.

In any case, I'd made some changes to my digital sources, I wanted them to settle down before adding some more unknowns to the system

Over the weekend, I replaced the stock printer cable with this purple accentuated one.

Wow! is all I can say....

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