RS150B Standby Mode - snap/pop noise - balanced Pre-OUT

Function IN/OUT Settings
#1

I’ve been using my RS150B for about 2 months now and occasionally experience an issue where there is an audible snap/pop from my speakers when using the remote to put the RS150B into standby mode. It’s pretty loud and is the same magnitude no matter the volume level on the RS150B before it happens.

A little background on how I’m using the RS150B…
the RS150B balanced XLR Pre-OUTs are connected to a pair of mono block amps. The system is in my home office and I frequently have to mute volume and/or pause playback during the day but when I know I’ll need silence for a while, I will place the unit in standby using the remote control. On average, I use standby about 5 or 6 times every day. I consciously make an effort to pause audio playback (typically ROON) before pressing the standby button on the remote.

Is anyone else experiencing an audible snap/pop from there speakers when their RS150B goes into or wakes up from standby mode?

I can hear a click noise, from inside the RS150B, when the unit goes into and out of standby. I assume there may be an electromechanical relay being used to switch the outputs ‘off’ when in standby mode. Does anyone know if there is a relay and if so, the type of relay and how it’s implemented?

Although my amps have external trigger inputs for on/off control, the RS150B does not have a trigger output. So I was hoping to simply use standby on the RS150B and leave my amps on all the time (the amps use Hypex’s NC500 OEM module and SMPS 1200 power supply). The occasional loud snap/pop has me concerned for the health of my speakers.

#2

Hello,

  1. What’s the model name of your amplifier?
  2. You can hear the noise only when you turn on/off standby mode?
  3. How much is the volume in ROSE?
  4. What do you play with RS150B usually?
  5. No matter if you’re playing something or not, the pop noise occurs when you turn on/off standby mode?

Best Regards,

#3

Hi @ROSELOA - appreciate the response. Answers to your questions and more detail below…

  1. Amplifiers are Bel Canto REF600M mono blocks
    https://belcantodesign.com/pdfs/UG_REF600M.pdf
  2. Yes, the snap/pop is very short duration, quite loud, and occurs exactly when the output ‘clicks’ off inside the RS150B (relay?)
  3. Volume is typically low (25-35) on the RS150B display. The snap/pop volume/amplitude seems to be the same regardless of volume setting but it’s hard to tell as it’s quite startling and only for a very short/instantaneous duration.
  4. I use ROON most of the time for source content on the RS150B. The only other device connected is an Oppo BDP-103 connected via a Toslink optical cable.
  5. The pop/snap noise does NOT occur during normal playback/use and does NOT occur every time I turn on standby. The issue has also occurred when I’ve turned off standby (via remote) with the intention of playing some music but got interrupted and/or forgot and just turned standby on again - no audible playback just standby OFF… followed by a period of inactivity… followed by standby ON and the snap/pop.

The interconnects I’m using for the RS150B balanced Pre-OUT to the REF600Ms are good quality XLRs with Mogami quad shielded cable and Neutrik connectors - nothing odd or esoteric. I have several sets in various lengths and have swapped them out but still have the issue.

I also have a single active subwoofer connected to the RCA Pre-OUTs on the RS150B. I don’t hear the snap/pop from the sub, just the stand mount main speakers powered by the REF600Ms. When it occurs, the snap/pop comes from the left/right main speakers simultaneously.

There seems to be a direct correlation between the internal click within the RS150B and the occasional loud snap/pop coming from my speakers.

Can you provide any detail with regard to how the RS150B sleep mode is implemented and what is controlling the analog outputs (in particular the XLRs) and the state transition from ON to OFF and OFF to ON?

  • Are electromechanical relays used?
    • If so, are all signal conductors (pins) for an output connection switched at the same time or just some of the pins?
    • Are the connector pins switched to an open state or something else?

Also curious if the RS150B volume is muted automatically before the ON/OFF or OFF/ON transition occurs - seems like this could be handled in the firmware, if it’s not already.

Thanks

#4

Hello,

Thank you very much for the video and detailed information.
It seems that more tests are needed here to determine a more specific cause.

Basically there is very very little POP noise when entering standby mode but it shouldn’t be that loud.

What I am currently suspicious of is the relationship between XLR and ROON.
If it’s okay, can I contact you after some more testing?
Also, in the post, you mentioned that you’ve tried other cables. Have you tried RCA cable as well?

#5

Hi -

I’ve used several different pairs of XLR cables to connect the RS150B balanced Pre-OUTs to the amps. My XLR cables only differ slightly in cable/connector… Mogami/Canary cables and Neutrik/Amp connectors. All the connectors are ‘pro’ grade with locking metal housings.

I use the unbalanced RCAs (both left & right) for my subwoofer connection. I have a single sub and the subwoofer’s internal amp handles summing the left/right channels, providing a ‘mono’ signal to the amp/driver. Both the RS150B balanced (XLR) and unbalanced (RCA) analog outputs are connected and active at the same time. I do not hear the snap/pop coming from the subwoofer when it occurs on the left/right main speakers.

Yes, please reach out after further testing or if any further detail or clarification is desired.

Thanks for assisting!

#6

Hi @ROSELOA -

I did some additional testing today and was able to isolate the standby snap/pop issue to the analog XLR Pre-OUT. Here’s what I tested (many, many, many times):

  1. Instead of ROON as the source, I used my Oppo BDP-103 that is connected to the optical digital input. During testing with that source, the snap/pop sound did occur several times upon activating standby on the RS150B.
    • the issue does NOT appear to be related to ROON
  2. I removed the subwoofer from the system and left the amps connected via the balanced XLR Pre-OUTs. I was able to replicate the snap/pop issue several times.
    • the issue does NOT appear to be related to the subwoofer
  3. I removed the XLRs from the configuration and connected the unbalanced RCA analog Pre-OUTs to the amps (sub woofer remained disconnected). I have yet to observe the snap/pop when activating standby on the RS150B. I used the remote control to activate standby numerous times and never had the snap/pop issue.
    • the issue DOES appear to be related to the balanced XLR Pre-OUTs!

Based on my testing, the issue is appears to be directly related to the balanced XLR Pre-OUTs. The issue (loud snap/pop noise) will occasionally occur when activating standby on the RS150B, regardless of the source/input or volume level selected when connected to an amplifier using the balanced Pre-OUT XLR connectors.

I have a few questions that would be very beneficial to know, so that I can better understand what may be happening.

  1. Can HiFi Rose provide an me with an electrical schematic for the RS150B?
  2. If no schematic can be provided, are you able to detail how the standby function is implemented?
    • Are relays used and if so…
      • what type of relay (solid state, electromechanical, etc.)?
      • are all pins/contacts for each output switched or only some?
      • what are the pins switched to (open, signal common, etc.)?

Best regards - Peter

1 Like
#7

The R250A (only RCA preout) also has a snap/pop sound from the speakers when entering and exiting standby mode.

Mark

#8

Mark - the issue still persists for me and there hasn’t been any followup from HiFi Rose. Hopefully @ROSELOA can review and provide an update.

Peter

#9

Hello,

Please check the message.

#10

Hi @PTinNC, if you are using the Rose device as the preamp - straight to a power amp - then the “thump” you are hearing is normal since there is no trigger controlling order.

Power amps amplify any signal being given to them. The balanced connections have a higher voltage than the RCA. Any changes in voltages when the relays kick in may cause a sound.

Normal procedure is to shut-down the power amps first, then the preamp/sources.

In my setup, I use a preamp between my RS150B and my Power Amp. With the system on, I can switch the RS150B in and out of standby with no noise since the preamp is still on. However, if I shut off the preamp before the amp, there will be a “thump” since the power amp is still on. My preamp does support a trigger circuit which shuts off the power amp before the preamp - helping prevent a thump sound.

Without a trigger, I would recommend the reverse order for shutdown - shut off the amp first, then the source. To start up, start the sources, then the amp last. This is common using separates.

I hope that helps. There are many articles describing the order.

#11

Hi @Manny - thanks for the suggestions and you are correct, I am using the RS150B as the ‘preamp’ in my system. The issue I experience does not occur every time the RS150B is placed into standby, it occurs randomly, and is not a ‘POW’ or ‘POP’ sound but rather a ‘SNAP’ sound. The random issue occurs even when streaming playback has been paused and the RS150B volume has been set to mute before entering standby. When powering my equipment on/off (using the power buttons), I use the tried and true method and order of operation you suggest.

The issue I have is that the RS150B marketing clearly shows the unit can be used as a ‘preamp’ with direct connections to amplifiers and powered speakers. I’m use both external amplifiers and powered speakers.

RS150B - Network Streaming UX
RS150B - Network Streaming UX985×418 54.6 KB

Having a trigger output on the RS150B may provide a work-around for some but in my case it won’t. I don’t find the defect in my specific RS150B or the deficient design/implementation on the part of HiFi Rose acceptable for the RS150B considering the price and how the unit is advertised.

My minimal equipment stack and how I use my system relies heavily on the STANDBY function/mode of the RS150B, which doesn’t appear to be working properly in my case. I raised this concern immediately upon experiencing the issue and have provided verbose detail and videos for HiFi Rose to review. @ROSELOA has been engaged and I am aware that my issue has been communicated to engineering and is under review… since I have been under the impression that others don’t experience the issue, I replied to @MarekZakupy’s post to remind HiFi Rose that I’m still awaiting an official response from engineering.

Regards - Peter

#12

Hi @PTinNC,
I was able to reproduce your issue…

For what it’s worth, I quickly rewired my system to use my RS150B as a preamp as you have. I obviously set the volume to software volume control - in case others are reading this and want to try - making sure to lowering the volume to a low level.

I then set my amp (I am using a McIntosh power amp) to on, instead of remote. This keeps the amp on.

I was able to instantly reproduce your loud SNAP sound through the speakers by placing the RS150B into standby. Yeah - that is a loud snap that would worry me about tweeter life.

In comparison, using my McIntosh preamp which has a trigger line between itself and the power amp is basically quiet when putting my preamp into standby mode.

I should also note that using my preamp, I NEVER get any sound when having the preamp and power amp on and I put the RS150B into standby. The preamp absorbs the voltage spike with no issues at the line level.

Looking at the preamp behaviors, I think preamps like the McIntosh have a soft mute function that slowly raises the volume and drops it to reduce this SNAP issue when starting and stopping.

Given that the RS150B is a computer, I would think that the Rose engineers ought to be able to address your problem through software by triggering a mute and reduction of voltage on the balanced outputs prior to engaging the main relays that disable that audio circuitry.

I didn’t try it, but I wonder if lowering the balanced output voltage levels would reduce the SNAP sound level if not eliminate it. The RS150B has a default 6.5V using the XLR balanced outputs. The RCA jacks are 2.2V. You can adjust those levels in the INPUT/OUTPUT settings are the RS150B.

Given that loud sound, I would shut off the amps first to protect the speakers until a resolution is found.

#13

Hi @Manny -

Thanks for your efforts to reproduce the issue and following up with the details. Ever since hearing the 1st snap, I’ve been using the remote to stop streaming playback and muting the volume before using the remote to put the RS150B into standby. I use Roon to stream Tidal, Qobuz, or from my local network 99.999% of the time. Even with this manual procedure and waiting 10’s of minutes between mute and standby… the snap will still occasionally occur. My workaround has been to pause playback, mute the volume, and leave the RS150B powered on.

As for voltage levels, I can’t use the lower fixed voltage options in my scenario and since I’ve been pausing play and muting the volume, I don’t really see how that would help. Additionally, I have used the RS150B with 5 different amplifiers from 3 different manufacturers (via XLR pre-outs) as well as a pair of powered monitors from another manufacturer and have experienced the issue with every combination. I use the RCA pre-outs for subwoofer integration. I’ve not noticed any undesirable behavior from the subs, which is most likely related to the low pass filters in the signal path (SVS subs with LPF enabled). The issue is most definitely the RS150B.

I’ve tried to find a way to quickly blank the display or have the clock display but that seems to require the Rose app and is not very straight forward. Pretty much unacceptable to me, especially at the RS150B’s price point. I’ve been patiently waiting and hoping HiFi Rose would fix the issue with a firmware update, as you’ve suggested… but that hasn’t happened yet.

It’s really a shame that the RS150B’s hardware and software features fail to align with it’s sticker price (not cheap) or sound quality (truly exceptional - to my ears, in my room).

I will respond/update the thread should anything change in the future. Fingers and toes crossed :slight_smile:

Best regards - Peter

#14

Same here with my 250a, popping sound mainly from left, always, no matter using the remote, which is still randomly blinking, or the power button. Annoying to be honest.

#15

Bonjour, j’ai le même problème sur mes blocs mono Cambridge edge M avez vous trouvé une solution ?

David

#16

Hi David -

HiFi Rose suggested replacing the analog board in my RS150B, which was done. After the replacement, the occurrence of the snap/pop, when the RS150B goes into standby, has been reduced but not completely eliminated.

  • Peter
#17

Bonjour Peter

Votre sujet date de juillet 2022 d’après l’étiquette présente sur celui que j’ai reçu la semaine dernière il a été fabriqué en septembre 2023 c’est triste que hifi rose n’ai pas réglé ce problème j’ai toujours mon cxnv2 bien moins cher et qui n’a pas de problème quand il est en xlr sur mes blocs mono j’ai aussi eu le dmp-a8 pendant deux semaines en test pas de problème non plus en xlr je n’ai pas aimé le son de celui ci.

au prix du rs150 et son placement haut de gamme c’est malheureux :somnolent: