Stellar Phono noise and interconnects for analog rig

Audio Components Preamplifiers
#1

I was wondering how to improve interconnects from TT (Technics SL1200G) to Phono (Stellar Phono Preamp) and from Phono to Preamp (BHK Preamp).

Actually I have full loom AQ Dragon (HC and Source) for all my system as for Power Cables. Soon AQ will launch a new range of IC and I am very excited even if I think that we will wait to read reviews, opinions on forums and so on.

Meanwhile my aim is to find the best (brand, material, geometry, characteristic):

RCA cables from TT to SPP
Ground wire with spades from TT to SPP
XLR cables from SPP to BHK Preamp

SQ is what I’m looking for and also to reduce hum, I noticed that if I switch the input from DAC to SPP I hear hum (as a motor noise in use) from speaker, on the contrary when the BHK Preamp input goes to DAC the speakers are very silent.

Also if I turn off the TT the hum is still there, otherwise it disappears if I turn off the SPP. in conclusion I suppose the analog ICs (mainly XLR from SPP to BHK Preamp) can help me to reduce the issue.

Already tried to manage cables in different ways and to keep TT and SPP far away from the other components, in fact both are now on a different shelf, isolated and well separated at a distance of 1.5 meter from any other piece of gear or wall output/current cables.

At the moment I use Ricable Invictus ICs (2k euro each) searching for upgrades.

I know this is a question for people who live in the “Al’s world” anyway I will appreciate suggestions from any kind of known and unknown universe.

#2

Investigating I found the noise is not TT dependant.

If I disconnect completely RCA and ground wire the noise is audible from the right speaker, from mids in particular.

Then I swapped the left/right XLR connectors (only in the BHK Input) and the noise went on the left speaker, following the right XLR output of the SPP.

With high gain the noise increases a lot, mainly from the right speaker but here also audible clearly now from the left speaker.

If I turn the rear knobs up and down, no differences at all. If I turn up the volume the noise increases.

If I disconnect the ground using the GND Defender (lifting the ground) hooked to the IEC of the SPP, noise still here.

At the end if I change the input channel of the BHK Preamp, then enabling the DAC source, no noise, therefore the SPP seems to produce the noise.

@jamesh can you help me?

Already called MPI dealer here in Italy and they suggested to send them for repair. Once again? I bought it in September and already had a substitution because the first one had an issue with the remote control if you remember. Now here we are again with another issue.

The noise were here since the unboxing, I lived with it and now just focused it comes from the SPP not tubes or preamp or any other component.

Not lucky with SPP, even if I love it.

#3

Did you try RCA interconnects from phono preamp to see if it’s a problem with the XLR connection?

#4

Yes I did. Noise still there at same level as XLR.

I tried also to move the PSS away from all other gears and nothing happened.

It seems the right channel is the problem.

Do you usually have different noise switching the BHK Preamp input from sources? When I listen to DSD SACD - DS SR DAC no noise, turning to SPP noise appears on the right speaker.

Volume level at 36-40 audible with ears close to speaker. At 50-60 audible from 50 cm. Over 60 from listening position.

1 Like
#5

Did you not have any other this noise with the original unit?

#6

The original unit never went on due to IR issue, unable to remove MUTE or any other control. So I couldn’t start listening with it.

#7

With the volume low so you don’t damage your speakers, what happens when you short your right phono preamp rca lead? Does it affect the hum? Touching the center hot in should produce hum, and shorting it to ground should stop it. Any other hum is probably the unit itself.

#8

I didn’t realize there are two phono inputs. Is the hum right channel on both inputs or just one?

#9

I disconnected completely RCA input from TT to SPP.

The only connection I’m trying is from SPP output to BHK Preamp input. Both XLR and RCA produce noise audible from right speaker. If I swap the BHK input right/left connectors, noise goes to left speaker.

#10

Sounds like it’s going back to the shop. As I mentioned, you could try shorting out the right channel phono preamp inputs to see if the hum stops, but that wouldn’t tell you how to fix it. By chance did you open up the unit to check for a loose wire or connector?

#11

Oh no, not that kind of skill able to open a machine and touch something I do not understand. Sorry I am a journalist, with my hands I’m able only to write not to manage any sort of technical thing.

If I roll a tube it’s a pain for me guys!

1 Like
#12

It was just a thought, maybe you would be lucky and find somthing loose. I’m always hesitant about opening new stuff that’s under warranty.

#13

Because it’s just in the one channel, I’m inclined to think something is wrong with the actual unit. If it were in both, I’d think it was maybe something with grounding. At this point I’d have the dealer take a look at it.

#14

Not so happy James as you can imagine but I always follow you!

I am sadly re boxing all one more time… I’ll keep you informed.

#15

We’re all pulling for you Luca—you are a very thorough and patient man! As the old saying goes—third time is a charm!!!

1 Like
#16

Yes, very sorry Luca. I completely understand how frustrating it can be. It stinks when these things happen. Hopefully the dealer is able to get you back up and running quickly!

#17

May we consider boxing and unboxing a sort of tweak? The aim is to find SQ improvements!

The very annoying thing is to stay without vinyls for a while (maybe a second unit would cover this risks). Hope time will pass speed.

There are bigger problems than this in our life, it means I will listen to some more CDs during next weeks.

#18

Good example of why having a back-up (or two) phono stage if it’s in ones budget. A simple, versatile, reliable pre that doesn’t break the bank is perfect…

Any local “audio friends” that can loan one to you? or maybe the dealer can supply you a loaner while making repairs to your SPP. Weeks or more of no vinyl is not something I would want to look forward to, first world problem, I know…

If you were closer, I would send you a “loaner” to get you by. I have a couple to choose from

Best,
-JP

1 Like
#19

So grateful for sharing with all of you thoughts and feelings, everybody here are similar in passionate love for music and its good and bad, cheap and expensive consequences.

Patience is The virtue of strong men, really don’t know if I can wait…

1 Like
#20

Fortunately in the EU and UK we have strong consumer laws and they ensure problems get sorted. They are very similar, due to EU Directives. You have full manufacturer protection for 2 years.

I would never advise anyone to try and fix the item beyond the user controls. Never advise anyone to start trying home electronics. You will only void the warranty.

Return the product to the dealer. The legal liability almost certainly lies with the Italian distributor. You should be able to get a new unit as a replacement.

If it is not fit for purpose, just return it. It is not your problem.

If you have a good dealer, they should lend you a phono amplifier.

I repeat, it is not your problem. The supplier should email you a return shipping label.

These days when phono stages hum should be long past. You have very expensive equipment. I’ve used the Vertere Phono and now use EAR Phonobox with 0.2mV Koetsu and get no hum at all, and they cost €1,200.

The Stellar Phono has excellent reviews in the UK. I almost bought one. One of the best in its class. I hope all goes well with the next one.

1 Like