My system has a noticeable turn on thump and I have always powered things up (and down) manually and in order. I now want to be able to power everything up at once and so I examined my system component by component. I found that the preamp is causing the turn on and off thump. (Without the preamp, there is a very small thump that I can live with.) The culprit is my Sumo Athena preamp, which sounds great and seems to be working well except for this problem. So, I would like some help in diagnosing and repairing this problem. Can anyone direct me to posts or articles on this subject?
One common strategy for avoiding preamp turn on spikes is to turn the power amp on after the preamp has stabilized. There are power management devices that do that. This device looks about right: https://www.monoprice.com/Product?p_id=604830&gclid=Cj0KCQjwz_TMBRD0ARIsADfk7hQVzk9BXUMipdl4W8TT7_yzgaBuFQ7OL0K45baDlBMrU2-1rvCcIVcaAmepEALw_wcB
Another strategy is to ensure that the power supply of the preamp stabilizes very rapidly or very slowly. Either strategy can work, or not. The theory of the fast stabilizing strategy is to let the preamp get stabilized before the power amp starts passing signals. The theory of slow stabilizing is to try to reduce the rate of stabilizing until it is so slow that any thumps that are created are at such a low frequency that they are below the bandpass of the power amp and get lost in its low frequency roll-off. Neither approach has to necessarily work, but either often may work.
Common means to accomplish these strategies is to make the power supply and coupling caps in the preamp either as large or small as possible consistent with general goals for adequate frequency response.
One common set of circumstances is that the electrolytic caps in the preamp degrade over time as they are naturally prone to do, and this essentially changes the design of the preamp. This is one way that re-capping or capacitor upgrades can yield real improvements. The sound is really no different, but the thumps may be reduced or eliminated.
Other strategies include simply throwing this legacy crap away and getting good modern gear that works right. A lot of modern gear does this by design. For example my fairly modern AVR is so digital that it has to boot which takes time, and it has a relay that doesn't hook up the speakers until the AVR finishes booting. This takes about 3-5 seconds. The other components in my system could be thumping away to high heaven, and by the time the speakers get hooked up, the excitement is all over.
Hello!I gave a try to Neutralizer and I'd like to thank you because it proposes a very interesting approach.
Many thanks for your answer.
As for the connection of 'bumps' and 'dips' in the highs, they can have very large amplitude (but narrow bandwidth) with headphones and, even worse, with IEM. Plus I guess those can be quite user dependent with IEM (depending on tips used, filters used and insertion depth). I would have been curious to see if it can be corrected with an EQ like Neutralizer.
But you might be right and the most important remains the general presentation. Plus I guess correction of large amplitude on narrow bandwidth may worsen things instead of correcting them (and introduce artefacts?).
Regarding excessive stereo separation, unfortunately, I cannot fix the tracks because I use streaming platforms. At the moment I am trying Qobuz and Spotify to assess which service suits me better. I will probably give a try to Tidal too.
In any case, I don't want to go back to the 'old fashioned way' for a lot of reasons, including:
Last post by ev13wt -
Welcome to room sound. You have two choices: Either believe what reviews and marketing and "general forums" say about EQ, or you can educate yourself to point where you will completely dismiss all that "fake news" (sorry)
Then you save 100 bucks and buy a measurement microphone. You have a computer obviously. http://mathaudio.com/room-eq.htm
You moved your speakers, now you have new "standing waves". The "bettering of bass" you experience after fiddling with decoupling is only your brain adjusting to the new sound. Keep going and one day it will simply feel "right". Its not of course. This burn-in of your brain to the new sound ... (get where I am going with this?)
For starters, you should read up / Google about "room modes" and "standing waves". If you want to go a bit further, read Floyd Tooles book: Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers and Rooms (Audio Engineering Society Presents)
I do like your 3 spikes idea - won't help with your problems of course, but the "self leveling" is a cool idea. Makes for tippy speakers if someone bumps into them.
When you're done reading, you measure your room with and without the spikes. Mark the speaker locations! Report back! It will be interesting to see the data.
Last post by robert -
If changing the language code to 'eng' is all it needed, well that's one of the changes 3.100 will have out of the box.
Go to Preferences/File/Add Location/
and write something like: spotify:album:401DhjeJg1yVIfBN2A55JY
where 401DhjeJg1yVIfBN2A55JY is the album code. To get the album codes I open Spotify Web Player. You need a premium account.
It works fine.
15 seconds sounds like an extremely long time though. My amp only takes ~3 seconds to click on after I press the power button. Maybe it's a typo and should read 1.5 seconds?
Last post by jazzthieve -
That might be a possibility too. I'd expect for someone to at least know what tags are.
Last post by Porcus -
Frankly, from the original posting (what you call "faulty logic" yourself), I would not bet money on the OP being right about what is called "tags" and what is merely order of appearance in a playlist.
A suggestion that will work if it is a "well-known" album:
Install MusicBrainz Picard - which is a useful application anyway, I'd say - and let it tag based on audio fingerprint.
Then auto-rename the files.
Check out this article
It states there is no switch on (or off) thump, so I assume there is a problem with your amp if it is indeed responsible for the thump
"I generally leave preamplifiers on all the time, and did so with the Athena as well. But for those who don't, the Sumo preamp has no turn-on or turn-off pulse; the output is muted for 15 seconds at turn-on to allow for stabilization of the circuitry—a welcome feature."
Last post by jazzthieve -
As I said, read the thread again. This is getting really stupid. Everyone here except you and OP seem to know it's just wrong tag titles and track numbers with the numbers and titles shifted one place. So that gets confused to a "sorting" problem with the tracks having "wrong audio". Seriously??