1 hour ago, Rustee said:

This is the info I got from my son.

 

Your son should be able to sort out an equaliser on your Pi. He may elect to install a different OS that has an good embedded EQ.

2 hours ago, Nada said:

a different OS that has an good embedded EQ.

Any suggestions of some that you recommend?

 

9 hours ago, Rustee said:

Any suggestions of some that you recommend?

 

Do you have a laptop?

13 minutes ago, Nada said:

 

 

Do you have a laptop?

yes

Whats the OS?

 

4 minutes ago, Nada said:

Whats the OS?

 

Mac OS 11.6

You might like to use your Mac to drive the DAC if your not up for Linux command line entries on the Pi and cant wait for your son to set it up.

 

With a 5m USB cable you can drive your DAC from the Mac. I dont use a Mac but there must be loads of options with  players with simple equalisers. Audivana gets good reviews. From there try music via Qobuz. They all come with free trials.

 

 

 

 

On 03/11/2022 at 9:59 PM, Nada said:

You might like to use your Mac to drive the DAC if your not up for Linux command line entries on the Pi and cant wait for your son to set it up.

 

With a 5m USB cable you can drive your DAC from the Mac. I dont use a Mac but there must be loads of options with  players with simple equalisers. Audivana gets good reviews. From there try music via Qobuz. They all come with free trials.

Hi @Nada I really should apologise for not looping back on this. I did have a play with a few options, however these weren't going to be of help when playing vinyl, which is the only time I really care about SQ. I pretty much only stream or play CD's when listening to background music while cooking, entertaining etc...

I may still delve into digital EQ at some, but for now I'm trying to maximise an app free system.

Appreciate your help all the same.

 

Cheers,

Russ

 

As per my post back on the 27th Oct 22, I was pretty happy with the improvements in my room.

I'm still using all the same treatments, including the ones I bring out when I'm alone like the panels that hang over the TV and place in the corners, and they really do make an audible difference to the top end sting.

 

At the start of the year I bought a pair of Yamaha NS1000m's and have been playing around with positioning, heights and attenuator levels. I think I have them sounding pretty good now and today, for the first time, I thought I'd take a measurement and see what their response is like compared to my Monitor Audio Silver 8's.

I also partly wanted to compare their bass response as I;ve been thinking about adding a pair of subs to the system.

 

Green is the NS1000m's

Red is the MA Silver 8's

 

Looks like a flatter in room response from the Yammies especially where the 2k dip is from the MA's.

45Hz room node still creating a hump, albeit a little less than what the MA's produced, difference between dual rear ported cabinet to a sealed cabinet maybe?? 

Surprisingly the Yammies didn't produce much less bass like I was expecting. 

One thing that did really surprise me is how the fr resp was so similar between about 75 to 400Hz between 2 completely different speakers, how is that possible.

 

Cheers,

Russ

Edited May 11, 20232 yr by Rustee

I am guessing that you placed the speakers in the same position? This is because of the Schroder frequency. This image is from Mitch Barnett's article: 

 

 

In other words - as long as both speakers are reasonably close in F/R below the Schroder frequency, the room will have a greater influence on the sound than the speaker. 

 

Above the Schroder frequency, we start to see differences. The most obvious is the low Q dip between 1.5kHz - 3.5kHz in your MA Silver 8's and the generally lumpy response. 

9 hours ago, Keith_W said:

I am guessing that you placed the speakers in the same position? This is because of the Schroder frequency. This image is from Mitch Barnett's article: 

 

 

In other words - as long as both speakers are reasonably close in F/R below the Schroder frequency, the room will have a greater influence on the sound than the speaker. 

 

Above the Schroder frequency, we start to see differences. The most obvious is the low Q dip between 1.5kHz - 3.5kHz in your MA Silver 8's and the generally lumpy response. 

Yes I do have the speakers in roughly the same position, a little further apart as they are a wider cabinet than the MA's.

 

Amazing, and that certainly explains the almost identical room response in the lower ranges. That link is great, I will need to read it a few times but very informative, thanks 

 

Cheers,

Russ

 

 

 

here is another online calculating tool to help understand the influence of the room based on the mathematics involving dimensions and frequency lengths

 

https://amcoustics.com/tools/amroc

 

12 hours ago, Keith_W said:

This image is from Mitch Barnett's article: 

 

 

and there goes any idea of me getting (WFH) work done this friday.... 😶

cheers! 

 

2 minutes ago, wasabijim said:

 

and there goes any idea of me getting (WFH) work done this friday.... 😶

cheers! 

 

 

You could blow your entire weekend reading these articles: link

5 minutes ago, Keith_W said:

 

You could blow your entire weekend reading these articles: link

oh dear

do you deal in nose candy too? 

 

I see the MB article also reference the amroc tool 

On 11/05/2023 at 8:42 PM, Rustee said:

 

 

 

Out of curiosity, I thought I would do some maths to estimate the size of your room just by looking at this graph. 

 

Curves diverge at 400Hz - therefore 400Hz is the end of the transition zone. The transition zone is 4*Fs, where Fs is the Schroder frequency. Therefore, the Schroder freq is 100Hz. 

 

The calculation for Fs is: Fs = 2000 * sqrt (T30/V). 

 

I don't know your T30, so i'll assume it is 0.3sec. Solving for V, we have a room volume of 120m^3. 

 

You have a bass peak at 45Hz. Assuming this is a standing wave, the wavelength should be about 7.5m. And assuming that you have a standard ceiling height of 2.7m and a rectangular listening room, we have room dimensions of 7.5 x 5.93 x 2.7m?

 

I checked your earlier post and saw a small looking listening room that seems to indicate my calculation is way off, but you have a rather large RT60 of 600ms, indicating that your room might be bigger than it looks? 

23 hours ago, Keith_W said:

I don't know your T30, so i'll assume it is 0.3sec. Solving for V, we have a room volume of 120m^3. 

 

T30 and T20 times below. I don't really understand the difference in how these two measurements are taken.

 

23 hours ago, Keith_W said:

You have a bass peak at 45Hz. Assuming this is a standing wave, the wavelength should be about 7.5m. And assuming that you have a standard ceiling height of 2.7m and a rectangular listening room, we have room dimensions of 7.5 x 5.93 x 2.7m?

 

I checked your earlier post and saw a small looking listening room that seems to indicate my calculation is way off, but you have a rather large RT60 of 600ms, indicating that your room might be bigger than it looks? 

 

You are spot on, there is more to the room than I showed in the photo. The small looking listening space is our lounge room, which is part of a larger L shaped room (consisting of lounge, dinning and kitchen).

 

The length of the lounge and dinning section is 7.5m (smack on with your calcs) and the width in the lounge section is 4.3m, but the dinning section does open into the kitchen as shown below, which may be why you got a large value for the width? Also the dotted line shows an opening (sorry my digital drawing skills have a lot to be desired!) which is the entry into the lounge area.

 

I hadn't really considered the rest of the room in my experiments and measurements, mainly because I don't have the freedom to acoustically treat those parts of the room. But it looks like they are having an impact on my measurements, much more than I thought.

Thank you for taking the time to have a play with those numbers, impressive how close you actually got and how you actually managed to work out that the room was actually bigger than the lounge I had previously shown.

 

Cheers,

Russ

 

 

 

 

Edited May 13, 20232 yr by Rustee

On 12/05/2023 at 11:30 AM, wasabijim said:

here is another online calculating tool to help understand the influence of the room based on the mathematics involving dimensions and frequency lengths

 

https://amcoustics.com/tools/amroc

 

Thanks, I'll have a look and play with that tool.

Cheers,

Russ

 

Yeah, there were a lot of things I didn't know about your room so I had to make a few assumptions - e.g. that you had a rectangular room, that the ceiling was a standard height, it was not vaulted, etc. You could probably EQ that bass peak out. If it was a null, it would be more difficult! 

On 11/05/2023 at 8:42 PM, Rustee said:

One thing that did really surprise me is how the fr resp was so similar between about 75 to 400Hz between 2 completely different speakers, how is that possible.

The room, and the position of the speakers and listener, in it ... is what dominates the response below ~300Hz.

14 hours ago, Rustee said:

T30 and T20 times below

I really don't recommend that people pay much attention to "RT".   It is not a great tool for small room accoustics.

 

Flat (vs your preffered target) frequency response

Eliminate any big "reflections" seen in the ETC chart

Even decay time (decay and waterfall charts)

 

On 13/05/2023 at 11:39 PM, Keith_W said:

that the ceiling was a standard height, it was not vaulted

I should have mentioned my ceiling is 2.4 not 2.7 and, thats correct, not vaulted.

 

On 13/05/2023 at 11:39 PM, Keith_W said:

You could probably EQ that bass peak out.

Ok so with this comment I have a couple questions.

 

I recently came very close to buying a pair of SVS SB1000 Pro subs that have PEQ via DSP (yes I was abou tto dip my toes into DSP!)

I cancelled the order for one main reason, time alignment. From what I have read the DSP on these subs introduce about 6ms of delay and there is no way I could move the subs closer to the listener. SVS don't seem to advertise this spec so it could be more than 6ms, I don't know.

• Would this delay be audible or have a realistic effect on my SQ if the rest of my system has no DSP and therefore no delay?
• Would a pair of subs be worth while in the sized room I have? My intention was to have a xKitz crossover built by @andyr so I could roll off the mains at about 60-80Hz and let the subs do the rest.

 

Watching this video at the 6min 22sec mark, the SVS app allows peaks to be reduced by up to about 10db (hard to tell exactly how far it goes).

 

 

Cheers,

Russ

 

29 minutes ago, Rustee said:

I recently came very close to buying a pair of SVS SB1000 Pro subs that have PEQ via DSP (yes I was about to dip my toes into DSP!)

I cancelled the order for one main reason, time alignment. From what I have read the DSP on these subs introduce about 6ms of delay and there is no way I could move the subs closer to the listener. SVS don't seem to advertise this spec so it could be more than 6ms, I don't know.

1. Would this delay be audible or have a realistic effect on my SQ if the rest of my system has no DSP and therefore no delay?
2. Would a pair of subs be worth while in the sized room I have? My intention was to have a xKitz crossover built by @andyr so I could roll off the mains at about 60-80Hz and let the subs do the rest.

 

My view, Russ, is that:

#1:  yes, that amount of delay would be detrimental.

#2: I'm a believer in having 2 subs, rather than just one - and keeping them as stereo subs (ie. a L and a R), rather than switching them both to mono.  (Some people here disagree with me!   )  If you place them adjacent to your mains - you've effectively created a pair of full range spkrs.

 

Note re. using analogue active XOs ... these have no 'extra' delay (unlike a DSP XO).  If you make up a stand for the mains (like we've discussed) so the subs are underneath the mains ... then you can position the subs to be time-aligned with your Yammie's woofer - and 24dB slopes at a 60-80Hz XO point will work very well.

 

1. 6ms is the same as putting your subs 17.5m away. Having said that, there are plenty of people who do not believe that it is audible. For context, a 20Hz wave takes 50ms to form, and a 50Hz wave takes 20ms. In a small room, a 20Hz wave would have reflected across your room a few times before the sub has finished generating the wave. The Haas effect ("law of the first wavefront") says that two sounds arriving at your eardrum have to be spaced > 40ms apart for it to be perceived as a separate sound or an echo. 

 

I think that a 6ms delay would be barely audible. I place interventions into 3 categories: (1) definitely makes a difference and I will spend money, (2) unsure if it makes a difference and I will do it if it's free or cheap, and (3) inaudible / makes no difference. For me, time aligning subwoofers belongs in the middle category. In my system, the time delay of my subs is 1.75ms. The audibility of this is highly questionable. BUT ... since I already have the ability to do it, I do it. If you don't have the ability, then I wouldn't worry too much about it. But then, I don't know how OCD you are about pursuing things you may or may not be able to hear ... 😁

 

2. Yes, two subs will definitely make a difference. Audibly and measurably. 

 

I didn't know that @andyr sold subs ... he never mentioned it to me! Hmmm ...

1 hour ago, Keith_W said:

6ms is the same as putting your subs 17.5m away.

 

Not quite, Keith!  

 

Speed of sound is approx 1100 fps - so 1ms represents approx 1.1 ft.  So 6ms is 6.6 ft ... or 2m.

 

1 hour ago, Keith_W said:

I didn't know that @andyr sold subs ... he never mentioned it to me! Hmmm ...

 

Nooo - I don't sell subs, Keith!