JDWest

Thanks for sharing that 👍

Well in that scenario you have actually done a listening test of the product in question and your observations should be respected.

A very real problem...for which I have no solution...is that there is a large number of forum members that stopped posting their listening impressions of cables and other devices/tweaks due to the inevitable responses. We are completely missing their input and that's a real bummer. Most members do aim for mutual respect and politeness but when one side's argument is effectively "you imagined it" and that gets repeated ad nauseam, then it's easy to understand if the other side is already a bit offended, regardless of the language used.

I agree...except that my first thought was to wonder about the test tracks being played. I think of a few of my favourite tracks that have more sibilance than I would like but my ATCs will simply reveal that and also the reveal lack of sibilance on other tracks. Regarding the bass, it is tight...comes and goes quickly...as it should IMO, providing the recording/mastering didn't alter that. Now that can lead some people to find ATCs a bit bass shy. "Too much harmonics"[in low end] makes me think that the opposite was experienced during this demo. Something in the recording or outside of the ATCs is my guess...but that's just IMO and YMMV etc. We all like what we like and don't need to justify that. Cheers, John

Glad I never had to choose between my wife and my ATCs. I would really, really miss her.

I think the term "bookshelf" confused some of us here; thought you were talking SCM 11s or 19 passives, which obviously have less bass than the higher models. "Classic" is the term for stand mount 50s and up. I spoke with ATC before upgrading my 100A Classics to 150As. They said there is no extra bass extension with Towers vs Classic. As @Tobes said, the working cabinet volume is the same. Indeed, ATC claim no sonic difference at all between Classic and Tower in the same range. I suppose some very minor difference is possible due to interaction with room but ATC suggested it is a purely aesthetic choice. I went with 150A towers anyway. The extra bass extension of my 150s compared to my 100s was quite obvious. This could potentially introduce more difficult issues with your room, I suppose. Cheers, John

Yes, the pricing on domestic versions has come down so I wouldn't expect that big a difference. You do pay a fair bit extra for the towers, special veneers and gloss finishes (as per Hi Fi show demo pair). ATC say they sound the same, though I can't rule out very minor differences. Apparently, the "effective internal volume" (I made that term up) is the same in towers vs Classic. I guess the towers have an extra cabinet section below. Both domestic models come with spikes, though no stands are included with Pro models. We recently got a new thread for ATC here; https://www.stereo.net.au/forums/topic/292410-atc-speakers-owners-discussion-thread/?tab=comments#comment-4382482 I'm an ATC dealer. Cheers, John

I'd better start by declaring that I'm the ATC dealer in WA. I have also owned ATC speakers since 1996 when I bought a pair of 100 actives...so feel free to assume I'm biased for one reason or the other. 😉 The tweeter and midrange driver are offset to reduce distortion by having different distances to the side edges of the baffle. The grill that fits around the baffle, has rounded edges to further reduce edge diffraction. In practice, the effects of grill on or grill off are quite subtle and owners are split about which they prefer sound-wise. As for tweeters in vs tweeters out, however, that change can be huge. @Misterioso I think you have it correct about distances to side walls. In a room that is nearly 10m long but only 4m wide, my current 150As and previous 100As sounded far better with tweeters inwards. Id recommend that as the default orientation. All of the domestic models, including towers are available in Australia. Apart from cabinet size and woofer size, the 50s/100s/150s are identical. The domestic models come with a quality wood veneer as standard. The professional models do not. Construction of the cabinets for domestic models is outsourced to a manufacturer of high end furniture. I have read that ATC build the cabinets for professional models themselves. The baffles of the professional models have a kind of "cut-out" that is visible and is intended for an alternative tweeter position if the monitors will be placed on their sides. Cheers, JD

I can't help you with the ProAc part of the comparison but if you want a demo of the ATC SCM 11s, I can certainly help with that. My service is much better than my website 😄. Not sure if your previous comparison used the newer design ATCs with the ATC built tweeter but in any case, you are more than welcome to come over, have a listen and see what you think. Cheers, John

$135, which includes the postage back to you. That's without changing the faceplate; extra $90 for that. Cheers, John (Sublime Hi Fi)

@frednork An easier way to access TOP is via the Snakeoil interface. Go to the System tab and click the button labelled TOP. Also, when you want to add a process priority in the Snakeoil tab, go to TOP first and note the exact spelling of the command. The commands that pop up near the top of the list are the ones of more interest. Use the same spelling when you enter them in Process Priority in the Snakeoil tab. If you set them at 99, then when you go back to TOP, you should see "rt" for that command in the PR column. Otherwise you'll see the number you entered. Note that TOP within Snakeoil may abbreviate the command name with a "+" at the end. It will still work typing that or you can use the full name as you see when ssh-ing into TOP. I can see that it didn't work in your last attempt because you only entered part of the command name. Here's an example from my system:

@rmpfyf Do you know another ssh method to shut down mobo USB hubs/ports? ...other than via uhubctl? I use a SOtM PCIe-USB card to DAC and don't use any mobo USB ports on my Gigabyte GA-B250M-HD3. Unfortunately, uhubctl doesn't detect my mobo's USB hubs; it only detects the ones connecting to my DAC (I can switch those off in Snakeoil). lsusb shows all the hubs. Cheers

I'm a bit confused. So in BIOS I do always enable HPET timer. You agree I think? Within Snakeoil web interface, I can select tsc, hpet or acpi_pm. I always select tsc (don't need an ssh command to do so). I think you find that a reasonable choice. Now, with HPET enabled in BIOS and tsc selected in Snakeoil, would the following command change anything?: echo "8192" | sudo tee --append /proc/sys/dev/hpet/max-user-freq OK, the number adjusts interrupt freq, so does the higher number mean that interrupts can happen faster?...or something like that.

@rmpfyf thanks kindly for the input. So many questions 😉 but I'll start with clocksource fequencies and these commands: echo "8192" | sudo tee --append /proc/sys/dev/hpet/max-user-freq echo "4095" | sudo tee --append /sys/class/rtc/rtc0/max_user_freq Within Snakeoil I found tsc sounded best for me. It also gave the best cyclictest results. In BIOS if I disabled HPET timer it sounded worse and cyclictest results were shocking. I don't know how this all relates; maybe it makes no sense and I did do different tests on different motherboards at different times. Anyway, I see hpet in one of the above commands and wanted to know if these commands need to change if I'm selecting tsc? For the numbers (8192 and 4095 seemed to work for me) is there any rule like needing to be a multiple of x or can I enter any number? Cheers

Open the Snakeoil tab in your browser again and force reload the page. That should tidy up the text. On Mac: Command + Shift + R On PC (not sure) Ctrl + Shift + R or Ctrl + F5

@rmpfyf you seem willing to teach us some ssh commands. I'm keen 😀. I'm comfortable sending ssh commands to my Snakeoil server from my Mac via Terminal but don't know many useful commands and I'm a linux novice; at best. I can display TOP and get it to show last used cpu core but wouldn't know how to assign a process to a CPU core. Better still, I would like to try turning some USB hubs/ports off but not sure it is possible with the USB hubs used in my mobo. In fact none of the mobos I've tried had any BIOS setting to turn off USB and Snakeoil doesn't seem to identify them as...hmmm...switchoffable. Cheers, JD

When activating CPUset in Snakeoil, if you get the error message say no processes running in user, firstly refresh the page and they might appear. That said, I also get zero processes for Roon Bridge but one for Roon Server. Don't have JRiver to test. Works fine for LMS/Squeezelite and as I recall also for MPD.

+1 for Snakeoil OS. Best I know of too. 👍 Let's be clear; it is an Ubuntu-based Linux operating system that has been stripped down to improve SQ and designed to make life easy for users with little or no knowledge of Linux. The whole premise of Snakeoil is to let the user choose what they like best. Different server/player software can be switched with a few clicks to decide what you like and then more tweaks are also just a few mouse clicks away. I've used it for years, with great support from Agent Kith, who is continuously improving the system; more user options, better SQ etc. I've used it with Roon (server, endpoint or both), LMS (server, Squeezelite player or both) and MPD. I've even used it to switch between different versions of Squeezelite and MPD. There are also other options available. Over time, I developed my own preferences regarding these server/player software but I won't mention which right now. I just want to point out that using Snakeoil is the opposite of being limited to any particular one of these software.

I take no responsibility; just sharing the link re input voltage changes; https://www.sotm-audio.com/sotmwp/english/sclk-ex-extra-power-input/

9V vs 12V; I couldn't hear the difference moving from a 12V ultra unit to a 9V ultra unit. That doesn't mean there was no diff. I wasn't really trying to pick small diffs. The thought has occurred to me that warmer temp of electronic components when run at 12V might be the reason that people seemed to prefer 12V for std sMS...but I speculate. SOtM would advise strongly against ever feeding a 9V unit with 12V. There is some leeway on voltages but feeding lower is safer than feeding higher. Maybe it would just run extra hot and shorten its life rather than blow up in the short term...but I'm not gonna try and would never recommend it to anyone. Uptone Audio JS-2 sounds excellent with Ultra IMO. Costs more than sPS-500 but you get a 2nd DC output. A well known Chinese brand of LPS that I also own cost much less and sounds like it cost much less...still better than a wall wart.

I'm a SOtM dealer. Hence my last reply being factual and sterile to meet forum rules. Kinda frustrating at times; keeping my opinions to myself does not come naturally to me 😉especially when it's a brand that I've spent a lot of time experimenting with. I own a master clock (non-SOtM) that I've used with the sMS-200ultra and with a DIY server containing the same SOtM clock board (sCLK-EX) coupled to their tX-USBexp PCIe-USB card. I have also tried many different power supplies with both. It seems that @Snoopy8 and @Bilbo are advising that @PeppaPig should save money by forgoing the master clock input and instead put that money towards the power supply because the SQ benefits are greater there; especially per $. So now I don't need to express my own opinion other than to commend those guys for their sound advice 😉😁

@Snoopy8 makes valid comments. Don't confuse the standard sMS-200, which has a very high input voltage range to the sMS-200ultra, which has a more narrow input range. For SQ, worry more about the quality of PSU you use than the internal voltage you select. Firstly, if you buy a new sMS-200ultra, the internal input voltage can be changed quite easily by moving jumpers, so if you choose the std 9V, you can always change it to 12V later. Older models required some soldering to make such changes. New models don't. If you also buy the sPS-500, it can output 7, 9 or 12V so you are covered for both 9V and 12V (and 7V; the jumpers can also be set to 6.5-8.5V input). IMO, the primary reason to choose 12V input would be if you already own a really good quality 12V PSU that you plan to use with the sMS-200ultra. Otherwise I'd lean towards the 9V as I think it will generate less heat. Someone here might suggest that 12V sounds better but make sure they are talking about the ultra with the same PSU. The quality of PSU makes an obvious difference to SQ so focus on that decision. The master clock input costs extra. You don't need to use a master clock if you get this option. It will work without one. If you do connect a master clock, you would ideally match the Ohms for best SQ. I believe that 50 Ohms is the more common master clock output so if in doubt, perhaps choose 50 Ohm input for the ultra. The SOtM master clock has 50 Ohms as standard but can be ordered for 75 Ohms. Other master clocks have both types of output. However, if you have a specific master clock in mind, then check which it uses. I just did a very quick google and saw some dCS clocks using 75 Ohms.

Oh, then that is a different remote to the one I used. Hopefully it is a remote that works with the amp.

New; they are often provided with 2 remotes; one has no battery and the other has a plastic sleeve that needs to be removed from battery. No 2nd remote? Check the battery. Maybe you can hijack same type of battery from some other remote.

(from memory)...the red light in power switch at back of unit near IEC inlet needs to be off; and then use remote to turn amp on. Just checking because it's easy to think that red light at the back indicates power on when really it means power off.