Arke
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Post by Arke on Mar 9, 2024 17:26:43 GMT
Ironically, Oli's room was easier to tune 'flat' than any other room. I wonder if that is to do with the short reverb times? Bigger the room the longer the reverb time. Have to confess despite some years now of studying this stuff I still really don't understand it fully. Where to start... There is no concise answer to this. I shall endeavour to write something more in depth soon. Essentially, it is a massive balancing act of many, many variables. You can never get anything perfect and you have to pick your battles. It's not just a matter of a 'ruler flat' tuning either. Ideally, I like to minimise interventions, so it is a balancing act. Oli's room is easy in many ways as variables are massively limited! The speaker placement and listening are pretty fixed, so these are mostly just accepted and you work with that. In a big room you often countless variables and it is extremely time consuming to optimise and can involve 1000s of measurements to slowly understand the effect of every single variable. In summary I am balancing: - dispersion and reflections - optimising decay times - optimising Midrange response - optimising HF response - Optimising soundstage depth, width and height - balancing transparency and richness/body/timbre - optimising the bass extension - optimising the linearity of the bass - minimising DSP intervention... Adding too much energy will increase distortion and is counterproductive. - minimising how hard the plate amp is working... Demanding a 20db boost can drastically reduce headroom and affect the performance and naturalness of the sound - minimise the measured THD at listening position, this is one of the most important IMO. Lower measured THD always sounds best, even if the FR is less flat. Too much intervention can increase distortion - there is always a sweet spot at which you reach minimum distortion with 'just the right' level of intervention. - optimise speaker placement with consideration of speaker boundary interference - Optimise toe in - understanding and working with port tunings - ports can be a pain. For example, a port tuning frequency near to a room mode is usually problematic. It is much harder to reduce the port output with DSP alone. I tend not to recommend any speaker with a port tuning on or near a main room mode. - Optimise speaker tilt fwds/backwards. - then there is just the magic, which is SO personal. I make changes and then listen for a week or two. Sometimes the best objectively doesn't float your boat. It's impossible to do that all that in one day, so I do my very best to optimise as much as possible - and that is client driven too! That is the concise answer! I could write many paragraphs on each point.
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Post by gninnam on Mar 10, 2024 9:23:13 GMT
Just finished reading Oli's update with fillets from Jason and sounds (no pun etc) like all the hard work (and cash) have been worth it. Great result and I hope you now have many years of enjoyment from what you have
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Post by bencat on Mar 10, 2024 12:39:44 GMT
Been just mulling over my thoughts and with no intention of making comments on speakers I have yet to hear pleas just accept this as just referred thoughts of someone with too much time on their hands . Now when I said fully active I was not really meaning DSP for the mid treble . While I like full DSP across all drivers I fully understand that others feel it is a bad thing and Jason has given good reasons why this might be the case. What I was thinking along the lines of was removing the cross overs out of the speaker cabinet palace that has vibration and magnetic fields all around and mount them in off board boxes . Then have an amplifier per driver feeding in to the cr . Yes more complication and cost but would this then improve the overall sound as each driver has its own dedicated amp with each amp working well within its best envelope . As I say I use both two way and three way set ups active and I use them with DSP which has always sounded better to me . But even the three way with no DSP just a crossover sounds better than the passive in all areas .
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Arke
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Post by Arke on Mar 10, 2024 12:51:13 GMT
Been just mulling over my thoughts and with no intention of making comments on speakers I have yet to hear pleas just accept this as just referred thoughts of someone with too much time on their hands . Now when I said fully active I was not really meaning DSP for the mid treble . While I like full DSP across all drivers I fully understand that others feel it is a bad thing and Jason has given good reasons why this might be the case. What I was thinking along the lines of was removing the cross overs out of the speaker cabinet palace that has vibration and magnetic fields all around and mount them in off board boxes . Then have an amplifier per driver feeding in to the cr . Yes more complication and cost but would this then improve the overall sound as each driver has its own dedicated amp with each amp working well within its best envelope . As I say I use both two way and three way set ups active and I use them with DSP which has always sounded better to me . But even the three way with no DSP just a crossover sounds better than the passive in all areas . Yes, when correctly implemented this would almost always give an uplift in performance (passive XO with dedicated amps for each driver). As always, it's a cost vs benefit trade off. All rooms seem to have big challenges for decent bass, so active below 100-200Hz has always worked better IME. The mid/treble enclosure of the Nextel 2Fs is an extremely easy load anyway, so they could be driven easily by virtually any amp.
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Post by macca on Mar 10, 2024 15:10:04 GMT
I'll dispute the idea that fully active is always better.
A lot of the time it is but only because many speakers offer a tricky load that many amplifiers can't cope with, including some quite expensive amplifiers.
I was seriously considering moving to actives (Kii 3) but, after three separate demos, I didn't in the end as they just weren't comprehensively better (although they were better in the bass) and ultimately just not as 'Likeable' *technical term* as what I have.
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Arke
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Post by Arke on Mar 10, 2024 15:16:46 GMT
I'll dispute the idea that fully active is always better. A lot of the time it is but only because many speakers offer a tricky load that many amplifiers can't cope with, including some quite expensive amplifiers. I was seriously considering moving to actives (Kii 3) but, after three separate demos, I didn't in the end as they just weren't comprehensively better (although they were better in the bass) and ultimately just not as 'Likeable' *technical term* as what I have. I'm confused? I was talking about passive on drivers with dedicated amps - perhaps just active on bass.... I deffo agree that fully active has many disadvantages and certainly something I wouldn't consider as better. Come and have a listen to Vaders or mini Vaders one day. I believe you can have better bass and 'likeable'.
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Post by macca on Mar 10, 2024 20:00:47 GMT
I'll dispute the idea that fully active is always better. A lot of the time it is but only because many speakers offer a tricky load that many amplifiers can't cope with, including some quite expensive amplifiers. I was seriously considering moving to actives (Kii 3) but, after three separate demos, I didn't in the end as they just weren't comprehensively better (although they were better in the bass) and ultimately just not as 'Likeable' *technical term* as what I have. I'm confused? I was talking about passive on drivers with dedicated amps - perhaps just active on bass.... I deffo agree that fully active has many disadvantages and certainly something I wouldn't consider as better. Come and have a listen to Vaders or mini Vaders one day. I believe you can have better bass and 'likeable'. Bencat was talking about fully active being better, which it is - sometimes. I am always thinking about new speakers, I've been obsessed with speakers from an early age Thing is every weekend when I sit down for some sessions I have to ask myself why I feel I need to change what I have. It will happen but I don't want to move in more big, heavy speakers before I get the house renovated - which I know you have just done yours so I'm sure you appreciate. But you are on my list. Hope to get a listen at Oli's place in the near-ish future. Don't actually think I need the adjustable bass, never had bass problems in this room even with big transmission lines. It always sounds even. But there are other options from Troels that interest me.
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Arke
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Post by Arke on Mar 10, 2024 20:05:49 GMT
I'm confused? I was talking about passive on drivers with dedicated amps - perhaps just active on bass.... I deffo agree that fully active has many disadvantages and certainly something I wouldn't consider as better. Come and have a listen to Vaders or mini Vaders one day. I believe you can have better bass and 'likeable'. Bencat was talking about fully active being better, which it is - sometimes. I am always thinking about new speakers, I've been obsessed with speakers from an early age Thing is every weekend when I sit down for some sessions I have to ask myself why I feel I need to change what I have. It will happen but I don't want to move in more big, heavy speakers before I get the house renovated - which I know you have just done yours so I'm sure you appreciate. But you are on my list. Hope to get a listen at Oli's place in the near-ish future. Don't actually think I need the adjustable bass, never had bass problems in this room even with big transmission lines. It always sounds even. But there are other options from Troels that interest me. Understand completely. No point rushing if you're happy where you are. I'll be interested to know what you think of Oli's. Always welcome here if you ever fancy a listen. Definitely wise to get any renovations sorted too. Enjoy the planning!
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Post by firebottle on Mar 16, 2024 18:49:58 GMT
I visited Oli yesterday to have a listen to the new speakers. I have heard a number of different speakers in his room and have a good handle on the problems encountered.
I know Oli was getting despondent about achieving a resolution so thank goodness for the talent of Jason to come up with the goods. The results are ASTOUNDING.
I have never heard such a completely balanced sound in a domestic environment, or any environment for that matter. I even thought the bass control and lack of colouration was as good as the quad electrostatic, but with the extension and slam that a panel speaker just can't give.
We listened to quite a few different tracks then Oli snuck in the beginning of an INXS tune, my god it was visceral. Stunning response and stunning clarity in what is after all a fairly small room.
Hats off to Oli for chasing the dream and hats off to Jason for fullfilling that dream, you really need to hear it.
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Arke
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Post by Arke on Mar 16, 2024 19:23:59 GMT
I visited Oli yesterday to have a listen to the new speakers. I have heard a number of different speakers in his room and have a good handle on the problems encountered. I know Oli was getting despondent about achieving a resolution so thank goodness for the talent of Jason to come up with the goods. The results are ASTOUNDING. I have never heard such a completely balanced sound in a domestic environment, or any environment for that matter. I even thought the bass control and lack of colouration was as good as the quad electrostatic, but with the extension and slam that a panel speaker just can't give. We listened to quite a few different tracks then Oli snuck in the beginning of an INXS tune, my god it was visceral. Stunning response and stunning clarity in what is after all a fairly small room. Hats off to Oli for chasing the dream and hats off to Jason for fullfilling that dream, you really need to hear it. Glad you liked them Alan. I knew we could achieve a very decent performance in Oli's room, but what we achieved far exceeded what I (and probably Oli) thought was possible. The bass in that small room shouldn't really be possible, but somehow is.
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Bigman80
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AA Founding Member & Bigbottle Audio Creator
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Post by Bigman80 on Mar 16, 2024 22:22:39 GMT
I visited Oli yesterday to have a listen to the new speakers. I have heard a number of different speakers in his room and have a good handle on the problems encountered. I know Oli was getting despondent about achieving a resolution so thank goodness for the talent of Jason to come up with the goods. The results are ASTOUNDING. I have never heard such a completely balanced sound in a domestic environment, or any environment for that matter. I even thought the bass control and lack of colouration was as good as the quad electrostatic, but with the extension and slam that a panel speaker just can't give. We listened to quite a few different tracks then Oli snuck in the beginning of an INXS tune, my god it was visceral. Stunning response and stunning clarity in what is after all a fairly small room. Hats off to Oli for chasing the dream and hats off to Jason for fullfilling that dream, you really need to hear it. Glad you enjoyed it Al, I must fess up, that INXS track was way louder than I'd intended. It scared the Sh#t out of me too 😂 That said, WOW....what power, depth and control! The comment you make about the electrostat like LF, the Mini Vader's do have that quality. I think it's due to the immense cleanliness of the sound and the cabinets being so ridiculously inert that the sound is uncolored by cabinet resonance. Arke Yes, LF of this quality, control, weight and power should not be possible in this small space. I should be wallowing in waves of mess, which is how life was before to varying degrees. However, the Minis have banished crap LF performance/control to history, BUT... One thing I am aware of is that whenever people hear these, they are going to be blown away by the LF performance...rightly so, it's immense, but there is a LOT more going on with this speaker than just pure quality LF...for instance, playing music that has no real LF from someone like Ladysmith Black Mambazo is now a complete different level of transparency, realism and clarity... certainly a move upwards from anything I have played it on here before. I know that the tweaked mid-LF behaviour will be having an affect, but it's not just the 20hz region that's benefited if you know what I mean. These are super special speakers. I am literally smiling ear to ear everytime I sit and listen to anything through them. Speaker and room interaction really is key. How lucky that Troels designed a pair for my room 😂 Honestly, getting these speakers has changed my Audiophile life. Listening to Steely Dan - Aja this evening...I was away in the music..not even thinking about anything else hifi related, just listening. What an absolute joy.
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Post by macca on Mar 17, 2024 9:07:07 GMT
''Could it be that I have found my home at last''
I think the problem with your room Bigman80 is that the Schroeder frequency is quite high so it's not just deep bass that's the problem. We don't think of middle C on the piano as a 'low note' but it's 262Hz, typical domestic room will have a Schroeder frequency somewhere between 100 and 200 Hz but it can be quite a bit higher than that, maybe as much as 350Hz. Below that everything is affected - i.e 90 percent of the musical content. Fix that and everything is better since most musical content is down quite low. And now you can enjoy a record that was (along with Concorde ofc) arguably the peak of human civilisation - especially the sacred second side Funny thing is you never see any of this mentioned in the hi-fi magazines. I used to buy Hi-Fi World every month for decades, I have hundreds of issues of it, plus many other hi-fi mags, and I don't think there's a single issue where anything about room/speaker interaction is mentioned, and the same is true for all the others. Despite it being the single most important factor in sound quality! By comparison all the other paraphernalia - DACs, cables, resolution, recording quality, and so on, pale into almost total insignificance. The industry is all about keeping us on the journey and making us forget that we ever had a final destination in mind back when we first got on board. Of course there's nothing wrong with still going on a day-trip somewhere, but it's good to have a home to return to. Even if we still remain tied to the mast.
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Post by jandl100 on Mar 17, 2024 10:28:34 GMT
Coo, fancy that. I've never even heard of the Schroeder Frequency before! I'm sure I've never seen it mentioned in any review or forum discussion. I wonder why? So thanks for that, Martin.
And, based on Alan's remarks, congrats to Jason and Oli on apparently conquering what is probably the worst room I have ever heard an audio system in.
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Post by macca on Mar 17, 2024 11:43:40 GMT
And, based on Alan's remarks, congrats to Jason and Oli on apparently conquering what is probably the worst room I have ever heard an audio system in. oh I don't know I can think of worse. My pal down the road has a room 12x13 - that wasn't easy to sort especially as he likes the minimalist look so hard floors, non-absorbent furniture and no clutter. Trick there was to use infinite baffle speaker (no ports) that had pretty much no bass. He's fine with that being a musician not an audiophile, personally I like bass that goes deep enough to be 'satisfying', which that set up doesn't do, but it still sounds balanced and he says visiting musicians compliment him on it and ask him where he got it from. It does have the advantage of a solid floor though and I think that's where the big problem with Oli's room is. Suspended floor is a sounding board. But tame the bass peak it created and then you're on a winner. When I went there to listen to the Ektas I didn't think it was so bad - bass went lower than in my set up - just much smaller soundstage and less space around the individual parts of the mix than I am used to, but you acclimatise to that. That's certainly a room effect, in general the bigger the better if you want big, open soundstage. I think on that day we probably did not listen to any music that would really set off the room.
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Bigman80
Grandmaster
AA Founding Member & Bigbottle Audio Creator
Posts: 16,142
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Post by Bigman80 on Mar 17, 2024 12:20:06 GMT
''Could it be that I have found my home at last''
I think the problem with your room Bigman80 is that the Schroeder frequency is quite high so it's not just deep bass that's the problem. We don't think of middle C on the piano as a 'low note' but it's 262Hz, typical domestic room will have a Schroeder frequency somewhere between 100 and 200 Hz but it can be quite a bit higher than that, maybe as much as 350Hz. Below that everything is affected - i.e 90 percent of the musical content. Fix that and everything is better since most musical content is down quite low. And now you can enjoy a record that was (along with Concorde ofc) arguably the peak of human civilisation - especially the sacred second side Funny thing is you never see any of this mentioned in the hi-fi magazines. I used to buy Hi-Fi World every month for decades, I have hundreds of issues of it, plus many other hi-fi mags, and I don't think there's a single issue where anything about room/speaker interaction is mentioned, and the same is true for all the others. Despite it being the single most important factor in sound quality! By comparison all the other paraphernalia - DACs, cables, resolution, recording quality, and so on, pale into almost total insignificance. The industry is all about keeping us on the journey and making us forget that we ever had a final destination in mind back when we first got on board. Of course there's nothing wrong with still going on a day-trip somewhere, but it's good to have a home to return to. Even if we still remain tied to the mast. I'd suspect you are right, but i can't check to confirm. It's definitely something i will look into though. The room speaker interaction is now at the forefront of my future advice to anyone who dare ask for it lol. This move to Mini Vaders and being able to tune out the biggest issues has changed my attitude to hifi in a big way. I will be especially interested to read what you think when you revisit here.
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Post by macca on Mar 17, 2024 12:37:50 GMT
''Could it be that I have found my home at last''
I think the problem with your room Bigman80 is that the Schroeder frequency is quite high so it's not just deep bass that's the problem. We don't think of middle C on the piano as a 'low note' but it's 262Hz, typical domestic room will have a Schroeder frequency somewhere between 100 and 200 Hz but it can be quite a bit higher than that, maybe as much as 350Hz. Below that everything is affected - i.e 90 percent of the musical content. Fix that and everything is better since most musical content is down quite low. And now you can enjoy a record that was (along with Concorde ofc) arguably the peak of human civilisation - especially the sacred second side Funny thing is you never see any of this mentioned in the hi-fi magazines. I used to buy Hi-Fi World every month for decades, I have hundreds of issues of it, plus many other hi-fi mags, and I don't think there's a single issue where anything about room/speaker interaction is mentioned, and the same is true for all the others. Despite it being the single most important factor in sound quality! By comparison all the other paraphernalia - DACs, cables, resolution, recording quality, and so on, pale into almost total insignificance. The industry is all about keeping us on the journey and making us forget that we ever had a final destination in mind back when we first got on board. Of course there's nothing wrong with still going on a day-trip somewhere, but it's good to have a home to return to. Even if we still remain tied to the mast. I'd suspect you are right, but i can't check to confirm. It's definitely something i will look into though. The room speaker interaction is now at the forefront of my future advice to anyone who dare ask for it lol. This move to Mini Vaders and being able to tune out the biggest issues has changed my attitude to hifi in a big way. I will be especially interested to read what you think when you revisit here. I will come down there, you'll have to let me know when is good for you. I'm having trouble getting time off right now as it's all hands to the pump (although we are slowly turning it around). I'm off six days over Easter but suspect that's not good for you - plus I have to go up to Liverpool for some of that. Some time in mid-April I might be able to do if that coincides.
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Post by stryder5 on Mar 17, 2024 12:45:54 GMT
Coo, fancy that. I've never even heard of the Schroeder Frequency before!
It’s the speed you take the cat out of the box and put it back in to see it’s state! 😂
Gary
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Post by macca on Mar 17, 2024 13:24:56 GMT
Coo, fancy that. I've never even heard of the Schroeder Frequency before! It’s the speed you take the cat out of the box and put it back in to see it’s state! 😂 Gary No it's frequency so it's the number of times you take the cat out of the box and put it back in*, not the speed. (* caution - cat may get mightily pissed-off with this process, especially if it's state is 'alive'.) Any way wasn't that Schroedinger?
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Arke
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Post by Arke on Mar 17, 2024 13:36:22 GMT
''Could it be that I have found my home at last''
I think the problem with your room Bigman80 is that the Schroeder frequency is quite high so it's not just deep bass that's the problem. We don't think of middle C on the piano as a 'low note' but it's 262Hz, typical domestic room will have a Schroeder frequency somewhere between 100 and 200 Hz but it can be quite a bit higher than that, maybe as much as 350Hz. Below that everything is affected - i.e 90 percent of the musical content. Fix that and everything is better since most musical content is down quite low. And now you can enjoy a record that was (along with Concorde ofc) arguably the peak of human civilisation - especially the sacred second side Funny thing is you never see any of this mentioned in the hi-fi magazines. I used to buy Hi-Fi World every month for decades, I have hundreds of issues of it, plus many other hi-fi mags, and I don't think there's a single issue where anything about room/speaker interaction is mentioned, and the same is true for all the others. Despite it being the single most important factor in sound quality! By comparison all the other paraphernalia - DACs, cables, resolution, recording quality, and so on, pale into almost total insignificance. The industry is all about keeping us on the journey and making us forget that we ever had a final destination in mind back when we first got on board. Of course there's nothing wrong with still going on a day-trip somewhere, but it's good to have a home to return to. Even if we still remain tied to the mast. Schroeder referred to the frequency at which rooms go from being resonators to being reflectors/diffusors as the “crossover frequency.” Below the Schroeder frequency (Fs) I would focus more on room tuning (if possible on the speakers) and countering peaks/nulls with bass trap treatment and speaker/listening position tweaking. Above the Schroeder frequency I am more concerned with decay times and reflections. I agree the Schroeder frequency will be relatively high in Oli's room, so more focus is on tuning and traps up to around 200Hz. The 10" bass driver (with DSP) rolls off 1st order at 150Hz, so there is scope to effectively adjust frequencies up to around 300Hz In any case, I always measure the frequency response, decay times and distortion at listening position and work to optimise all of these. The Fs is a great way to indicate how you may address certain challenges. EDIT: just checked the data and Oli's Schroeder frequency (Fs) is around 200Hz. My room is around 145Hz.
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Post by pete on Mar 17, 2024 14:37:31 GMT
''Could it be that I have found my home at last''
I think the problem with your room Bigman80 is that the Schroeder frequency is quite high so it's not just deep bass that's the problem. We don't think of middle C on the piano as a 'low note' but it's 262Hz, typical domestic room will have a Schroeder frequency somewhere between 100 and 200 Hz but it can be quite a bit higher than that, maybe as much as 350Hz. Below that everything is affected - i.e 90 percent of the musical content. Fix that and everything is better since most musical content is down quite low. And now you can enjoy a record that was (along with Concorde ofc) arguably the peak of human civilisation - especially the sacred second side Funny thing is you never see any of this mentioned in the hi-fi magazines. I used to buy Hi-Fi World every month for decades, I have hundreds of issues of it, plus many other hi-fi mags, and I don't think there's a single issue where anything about room/speaker interaction is mentioned, and the same is true for all the others. Despite it being the single most important factor in sound quality! By comparison all the other paraphernalia - DACs, cables, resolution, recording quality, and so on, pale into almost total insignificance. The industry is all about keeping us on the journey and making us forget that we ever had a final destination in mind back when we first got on board. Of course there's nothing wrong with still going on a day-trip somewhere, but it's good to have a home to return to. Even if we still remain tied to the mast. Schroeder referred to the frequency at which rooms go from being resonators to being reflectors/diffusors as the “crossover frequency.” Below the Schroeder frequency (Fs) I would focus more on room tuning (if possible on the speakers) and countering peaks/nulls with bass trap treatment and speaker/listening position tweaking. Above the Schroeder frequency I am more concerned with decay times and reflections. I agree the Schroeder frequency will be relatively high in Oli's room, so more focus is on tuning and traps up to around 200Hz. The 10" bass driver (with DSP) rolls off 1st order at 150Hz, so there is scope to effectively adjust frequencies up to around 300Hz In any case, I always measure the frequency response, decay times and distortion at listening position and work to optimise all of these. The Fs is a great way to indicate how you may address certain challenges. EDIT: just checked the data and Oli's Schroeder frequency (Fs) is around 200Hz. My room is around 145Hz. Do you have the data on what it was in my room Arke ?
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Arke
Moderator
Posts: 1,020
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Post by Arke on Mar 17, 2024 14:48:21 GMT
For those interested, here are the frequency response plots for the NEXTEL 2F with different levels of tuning in Oli's room. The red line is ONLY the mid/bass and tweeter operating, so the 10" driver is switched off and the mid/bass port is open. This is pretty bad to start, although I see plots nearly this bad in most rooms. It is evident that even the small 6.5" mid/bass is really energising the room at 40Hz - I hadn't expected this to be so prominent. The large suckout happens in every room and is the rear boundary interference. At a certain frequency the reflected wave off the rear wall is cancelling the wave from the speaker driver, due to a 180 degree phase shift. This frequency corresponds to a wavelength at 4 times the driver distance from the rear wall. In Oli's room this causes a big suckout at around 110-115Hz. The Blue line shows the 10" driver running with a *flat* (no tuning) output and the mid/bass port is still open. Here we can see that the massive suckout at 110-115Hz is mostly gone. This is because the 10" driver is rear mounted, so much closer to the wall - the large suckout is mostly solved without too much tuning invention, very good news! The boom at 40Hz is now even worse as we have two drivers energising the room. The green line is with the mid/bass port lightly stuffed and the 10" driver with tuning. We have now removed the 40Hz room mode excitation and boosted the response from 20-30Hz. The suckout at 100-140Hz has been lifted slighty.
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Arke
Moderator
Posts: 1,020
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Post by Arke on Mar 17, 2024 14:49:16 GMT
Schroeder referred to the frequency at which rooms go from being resonators to being reflectors/diffusors as the “crossover frequency.” Below the Schroeder frequency (Fs) I would focus more on room tuning (if possible on the speakers) and countering peaks/nulls with bass trap treatment and speaker/listening position tweaking. Above the Schroeder frequency I am more concerned with decay times and reflections. I agree the Schroeder frequency will be relatively high in Oli's room, so more focus is on tuning and traps up to around 200Hz. The 10" bass driver (with DSP) rolls off 1st order at 150Hz, so there is scope to effectively adjust frequencies up to around 300Hz In any case, I always measure the frequency response, decay times and distortion at listening position and work to optimise all of these. The Fs is a great way to indicate how you may address certain challenges. EDIT: just checked the data and Oli's Schroeder frequency (Fs) is around 200Hz. My room is around 145Hz. Do you have the data on what it was in my room Arke ? Remind me of your room length, height and width?
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Post by macca on Mar 17, 2024 15:06:33 GMT
''Could it be that I have found my home at last''
I think the problem with your room Bigman80 is that the Schroeder frequency is quite high so it's not just deep bass that's the problem. We don't think of middle C on the piano as a 'low note' but it's 262Hz, typical domestic room will have a Schroeder frequency somewhere between 100 and 200 Hz but it can be quite a bit higher than that, maybe as much as 350Hz. Below that everything is affected - i.e 90 percent of the musical content. Fix that and everything is better since most musical content is down quite low. And now you can enjoy a record that was (along with Concorde ofc) arguably the peak of human civilisation - especially the sacred second side Funny thing is you never see any of this mentioned in the hi-fi magazines. I used to buy Hi-Fi World every month for decades, I have hundreds of issues of it, plus many other hi-fi mags, and I don't think there's a single issue where anything about room/speaker interaction is mentioned, and the same is true for all the others. Despite it being the single most important factor in sound quality! By comparison all the other paraphernalia - DACs, cables, resolution, recording quality, and so on, pale into almost total insignificance. The industry is all about keeping us on the journey and making us forget that we ever had a final destination in mind back when we first got on board. Of course there's nothing wrong with still going on a day-trip somewhere, but it's good to have a home to return to. Even if we still remain tied to the mast. EDIT: just checked the data and Oli's Schroeder frequency (Fs) is around 200Hz. My room is around 145Hz. Lower than I thought it might be. Pretty normal then.
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Post by macca on Mar 17, 2024 15:11:20 GMT
For those interested, here are the frequency response plots for the NEXTEL 2F with different levels of tuning in Oli's room. The red line is ONLY the mid/bass and tweeter operating, so the 10" driver is switched off and the mid/bass port is open. This is pretty bad to start, although I see plots nearly this bad in most rooms. It is evident that even the small 6.5" mid/bass is really energising the room at 40Hz - I hadn't expected this to be so prominent. The large suckout happens in every room and is the rear boundary interference. At a certain frequency the reflected wave off the rear wall is cancelling the wave from the speaker driver, due to a 180 degree phase shift. This frequency corresponds to a wavelength at 4 times the driver distance from the rear wall. In Oli's room this causes a big suckout at around 110-115Hz. The Blue line shows the 10" driver running with a *flat* (no tuning) output and the mid/bass port is still open. Here we can see that the massive suckout at 110-115Hz is mostly gone. This is because the 10" driver is rear mounted, so much closer to the wall - the large suckout is mostly solved without too much tuning invention, very good news! The boom at 40Hz is now even worse as we have two drivers energising the room. The green line is with the mid/bass port lightly stuffed and the 10" driver with tuning. We have now removed the 40Hz room mode excitation and boosted the response from 20-30Hz. The suckout at 100-140Hz has been lifted slighty. That's a great response - practically textbook. My front wall return is 32Hz so no problem there, the speakers don't go that low! So useful to be able to do this stuff. Not around when I started out we had to learn what worked and what didn't by trial and error. Eventually you get surprised very seldom - although does still happen that it shouldn't work but does, or it should work but doesn't!
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Arke
Moderator
Posts: 1,020
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Post by Arke on Mar 17, 2024 15:12:17 GMT
EDIT: just checked the data and Oli's Schroeder frequency (Fs) is around 200Hz. My room is around 145Hz. Lower than I thought it might be. Pretty normal then. His room has a very low (RT60) decay time around 250ms - mainly because its a small room room and he has a fair bit of treatment. A lower Decay time brings the Fs down. Fs = 2000*(SQRT(DT/RV)) = 2000*(SQRT(0.25/24)) = 203Hz DT is decay time (seconds) and RV is room volume (m^3)
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Post by macca on Mar 17, 2024 15:17:06 GMT
Yes, that makes sense. No idea what the RT60 is in my room so I can't calculate the Schroeder.
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Arke
Moderator
Posts: 1,020
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Post by Arke on Mar 17, 2024 15:22:08 GMT
For those interested, here are the frequency response plots for the NEXTEL 2F with different levels of tuning in Oli's room. The red line is ONLY the mid/bass and tweeter operating, so the 10" driver is switched off and the mid/bass port is open. This is pretty bad to start, although I see plots nearly this bad in most rooms. It is evident that even the small 6.5" mid/bass is really energising the room at 40Hz - I hadn't expected this to be so prominent. The large suckout happens in every room and is the rear boundary interference. At a certain frequency the reflected wave off the rear wall is cancelling the wave from the speaker driver, due to a 180 degree phase shift. This frequency corresponds to a wavelength at 4 times the driver distance from the rear wall. In Oli's room this causes a big suckout at around 110-115Hz. The Blue line shows the 10" driver running with a *flat* (no tuning) output and the mid/bass port is still open. Here we can see that the massive suckout at 110-115Hz is mostly gone. This is because the 10" driver is rear mounted, so much closer to the wall - the large suckout is mostly solved without too much tuning invention, very good news! The boom at 40Hz is now even worse as we have two drivers energising the room. The green line is with the mid/bass port lightly stuffed and the 10" driver with tuning. We have now removed the 40Hz room mode excitation and boosted the response from 20-30Hz. The suckout at 100-140Hz has been lifted slighty. That's a great response - practically textbook. My front wall return is 32Hz so no problem there, the speakers don't go that low! So useful to be able to do this stuff. Not around when I started out we had to learn what worked and what didn't by trial and error. Eventually you get surprised very seldom - although does still happen that it shouldn't work but does, or it should work but doesn't! It's the great advantage of room tuning. This is Oli's Nextels (green), Mark's CNO4s (blue) and my CNO4s (red) all in our rooms. All pretty consistent and all have tight, controlled and deep bass. I don't have Chris's measurements as he has been tweaking.
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Arke
Moderator
Posts: 1,020
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Post by Arke on Mar 17, 2024 15:22:33 GMT
Yes, that makes sense. No idea what the RT60 is in my room so I can't calculate the Schroeder. Need a mic for that.
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Post by antonio on Mar 17, 2024 15:25:55 GMT
That's all gone over my head, except for macca's funny post about the amount of times you put in/take out the cat, but as long as everyone's happy all's good.
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Arke
Moderator
Posts: 1,020
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Post by Arke on Mar 17, 2024 15:32:04 GMT
That's a great response - practically textbook. My front wall return is 32Hz so no problem there, the speakers don't go that low! So useful to be able to do this stuff. Not around when I started out we had to learn what worked and what didn't by trial and error. Eventually you get surprised very seldom - although does still happen that it shouldn't work but does, or it should work but doesn't! It's the great advantage of room tuning. This is Oli's Nextels (green), Mark's CNO4s (blue) and my CNO4s (red) all in our rooms. All pretty consistent and all have tight, controlled and deep bass. I don't have Chris's measurements as he has been tweaking. macca - For comparison, these are different passive speakers in different rooms. I have removed the legend so the speakers/room can remain anonymous!
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