John Curl's Blowtorch preamplifier part III

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Which of the three circulating (quite different in what to hear for) “versions” convey what you have experienced (or none of them)? <snip>

I have now had some time to digest and reacquaint myself with my own old write-ups. I also read the WBF thread. And now I have some comments.....

The WBF thread was really good. I have no idea if the initial post was based on my write up in 2009 on Audiocircle, or was from the Iron Chef posting by someone else or from the write up from the top link that was something that I wrote up for Arthur Salvatore and he reposted it. The "instructions" posted in the initial WBF thread was fairly identical to what I learned from my acquaintance, who is a certified MASTERS instructor of many years. I was surprised to read that another MASTERS certified instructor raised some issues over what was written. And like some of the later posters, I felt really frustrated that there is this air of secrecy about the MASTERS protocol.

It is interesting to note that JC mentioned in his post that John Hunter freely talked about what he was doing. While it may have gone over most people's heads, I likely would have understood much of it.

I can only say that my write up contains the same errors as in the initial WBF posting. I did not go thru the 3 day MASTERS seminar and all my information is second hand interpretation. But I have heard professionally done MASTERS set ups, so I know that it all works very well, and far better than anything else anyone does. Following the posted instructions will get you most of the way there.
I also thought much of what was written in the Genesis link was quite useful. I have also read the other links and I think them mostly useless.

I liked Dan's explanation in regards the comparison to a live sound mix. I would assume most people go to live music on occasion. Unless the venue is small and boxy, you can pretty much count on good sound balance thru the venue sound system. In other words, it will sound about right for the most part. And if you move around the venue, the musicians making the sound will not move around with you. If you are in an acoustic venue, which is even better as you hear the actual musical instruments making the sound, the music also stays in the same place if you move around.
Try that at home!!! Can you move around your music room and not have the music move around with you. Do you have to sit in just one certain spot? Do you have to hold your head perfectly still?

Lastly, I learned about this MASTERS stuff quite by accident. I visited a room at an audio show and the proprietor of the room was an old acquaintance and I only stopped in to say hello. I sat in the end seat of a single row of about 7 seats, worst spot in the room. I waited for my turn to sit in the middle, which is always the best place, or so I thought. The sound at my initial seat was pretty good, much to my surprise. When I got my opportunity to sit in the prized middle seat, I was really surprised when the sound was exactly the same. It was stunning really. I stayed in the room for 2-3 hours trying to learn everything I could. I remember well too. There was another person doing the same. Everyone else would just listen to a tune and then get up an leave, as if................well I don't know but they got up and left.

The sound of the music was non fatiguing, not full of clashing distortions. It sounded like natural sounding music. It was the closest thing to live music in electronic playback I had ever heard. It was all because of how the speakers were set in that room, and had really nothing to do with the equipment being used.

I was so impressed that over time I wrote the write ups that I did and tried to share as much as I could. Even though I now know that I am full of errors, it's still the best way to put speakers in a room that I have ever come across, and gives my lasting musical enjoyment on a daily basis.
 
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Dan, Very excellent write up about the what happens.
Thanks Stevo, and that was without bothering to read the links posted. It's what I do and have always done ie get the bass to sound musically correct or 'right' and then the rest does indeed mostly 'fall into place'. The surprising part is how little shift in mains speaker positioning is required to get it right or get it wrong. Things go to another level of precision in positionings required when a sub is introduced into the system, but when the sub AND L/R positioning is right the system very nicely goes to the 'next level' with articulation and coherence, level and sense of power in the bottom end bass that two speakers alone can never achieve. Another nice bonus is tweaking the sub controls (level and lpf) to compensate sub par recordings or to taste or to situation. It is obvious that mixing/mastering in the low end is highly variable no doubt due to inadequate monitoring during mix/mastering, with large level and tonal variation. Another observation is that with programme containing containing bass that is tonally 'right', the sub lpf filter can be turned to higher f, and the level can be increased to couch/carpet/room shuddering blissful fun. Other tracks where the bass is 'wrong' the sub level and lpf settings become quite critical and the best result is not badly 'wrong' however never never quite 'right'. A confirmation of system setup is to go to other rooms (especially the kitchen lol) or outside....if the sound going over the fence sounds 'right' the neighbours don't complain, and if the sound in the kitchen is good the cook don't complain and the food is good/safe to eat.

Dan.
 
The Genesis link mentions the effect of small movements, like 2mm, on the sound. I used to hear this all the time from Rod when he was talking about Master Set, where a "large" movement would be 1/4 of an inch and most movements were like 1/16th. When you get close, those small movements make a good difference. I once overheard a pair talking at an audio show and one mentioned how surprised he found that 1/16th movement would make in the sound of the speakers. Of course that only works when you have it really close, otherwise....no.

Ya, gotta keep the cook in the kitchen happy!!!!!

Here is a link that explains everything very well. Be sure to watch the video in the first post as the speaker goes through the process of setting up the speakers. HIGHLY RECOMMENDED.
Much of the thread discussion has post by Metaphacts, from WBF link, and is very good.

Guide to Speaker Placement - AudioAficionado.org
 
Yeah, that's what I was getting at. Incremental 2D positioning over large range will reveal 'nodal' spots that work or don't work well with the room with variation in the overall sound according to which particular 'nodal' point position. The first stage is to finely optimise positioning at each of a selected set of nodal points and note/mark these positions and then duplicate the process for the other speaker. The two speakers now sound individually good in the room but things change with both speakers running and the result can be that they don't play nice together......this is all too often the result when aesthetic factors dominate. The last stage is to find the speaker positions where each speaker individually sounds good AND also plays nice with each other speaker and this may come down to mere mm's of movement or single degrees of angle change. When this is achieved the room and the house essentially disappears and becomes the foundation of the performance.

System dependencies become less obtrusive when this speaker fine position tuning is optimised, and system deficiencies become sins of omission rather than sins of embellishment. Speaker driven acoustic room resonances represent both increase in system efficiency and return of room stored energy back to the individual speakers. This translates to increase of amplifier load impedance, and backfeeding input to the amplifier of transduced room acoustic energy. This means that the amplifier is delivering energy into a 'wild' load (speakers and room combination) and this causes a cloud of distortion products dependent on the capability/performance of the amplifier. Zero loop feedback amplifiers and tube amplifiers go long ways to reducing this amplifier room/speaker dependency, as does proper speaker impedance equalisation as in Joe's Elsinore loudspeakers. System, speakers and room need to be treated as a complete ecosystem for optimal sound and some room damping is required but it is easy to go wrong with damping in terms of positions of damping, degree of damping and spectral nature of damping. The first place for damping is behind the speakers to control early reflections that through localised addition or cancellation play havoc with perceived imaging, FR and distortions at the listening positioning. AC power quality, gear, cables, Myrtle blocks etc all combine in the audio ecosystem and contribute in different and interactive ways to further control the inhouse sound, but speaker positioning is the primary and mission critical factor, which then serves to highlight system attributes and deficiencies both. The ultimate achievement is 'surround' sound anywhere in the house or outside and no vice like 'sweet spot'. I could go on, but achieving good sound is not difficult and ought not to be a 'black art'.

I understand that the well heeled enthusiast is prepared to pay well for a different and experienced pair of ears to achieve optimisation....they consider it as cost of ownership. Indeed I spent the best part of a day listening to a selection of tracks over and over whilst setting up a new installation of a Genesis 1 system in a suitably huge room...16m by 9m or so and with angled corners behind the speakers. Once we got it 'dialed in' the result was one that totally rewrote my experiences and expectations of how seriously good a home system can be, and for certain not experienced by most amateurs/enthusiasts here on this forum. Same goes with my experiences of 'doctoring' live PA systems.....when it's dialed in correctly perceived distortions disappear and the room and band together become the experience with good sound at all positions throughout the venue. Interestingly the bar staff perk up, smiling and having fun, and commenting on sound quality....they get to hear plenty of bad stage sound and bad mixes.....good sound coherence makes for easier vocal communication (over the bar) over seriously loud sound. Ditto the audiences, properly good sound changes the whole dynamic of the venue and makes for a fun show.

Ya, gotta keep the cook in the kitchen happy!!!!!
Let her be the DJ too whist cooking is the safest ime.

Dan.
 
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In consideration, I am not sure if I could handle an 'optimum set-up' for my speakers in my apt. It reminds me of the time when Enid Lumley would set up my hi fi, back in the early 80's. She wanted us to move the TV that was between the speakers. I guess it would have helped, but it was just too much of a compromise.
In evaluating my living room at the moment, it would be the same. Yet, I am perfectly happy with my speaker positions (for the most part) especially the Met7's. Am I just used to it? Perhaps.
 
I reinforce the comment/observation that speakers that are not position optimised produce distortions that cause masking of low level detail and this observation is confirmed in the YT clip with the comment of 'revealing stuff didn't know was there'. So the naysayers who insist that cables and other tweaks etc have no audible effect may be correct in that observation for their system because speaker positioning is not optimised. I don't understand that speaker positioning is generally so misunderstood......I have employed this method since as a teenager building my first speakers and ever since.....it has always been intuitive to me but perhaps I am an outlier in this. Another possible reason is that the average listener/enthusiast succumbs to external factors like room decor WAF etc and is denied the possibility of optimal positioning. How many here employ the linked/discussed method to optimise speaker positioning ?.

Scott, your Met 7's are in overview pretty similar to Bose 301's or Bose Studiocraft with paper 8" and paper tweeters. With careful positioning I have heard 301's to sound pretty damn good/fun on rock/punk music although I have never gone so far as the kinds of 'industrial' music you link to periodically. The likes of 8" two ways are pretty sensitive to placement and even minor suboptimal placement will very quickly destroy imaging and low level detail and musicality, and also don't really cut it for low end power into the room.....impression of bottom bass but no real grunt. I use an active 8" sub to augment the bottom low end, and with all three speakers position optimised I get rock solid cranking bottom end that vibrates the whole house and surfaces like kitchen counters, shelves and desk tops (and brick walls, doors etc) BUT this adds to the experience because these items/surfaces are being driven tunefully. I also get 3D sound from the non critical listening position as noted in the YT video, and throughout the house and out in the frontyard and backyard the sound is big, clean, clear and tuneful.

I linked Buzzsaw Popstar the other day, Aloha Steve And Danno is another interesting track. Both tracks are full of fuzzed out fast guitar, up front vocals and big bass but both tracks are also quite the masterpiece in depth and placements and when heard correctly and are (to me) just plain good/fun and excellent recording/production.

This kind of music (and industrial and metal) very easily turns into a 'wall of noise' with bad speaker placement and consequently clever detail/production values are obscured and lost......in such case it is no wonder that power conditioning, opamp rolling or cables etc make no real subjective difference, same with tweaks like Myrtle blocks lol etc.

Youtube comment - So if these so-called experts, selling such high-price tagged equipment, writing for magazines, boosting of their academic credentials, don't even know how to voice their own systems, should we be listening to them at all!!! That's not a question.
Scott, have you troubled to optimise your Met 7 speaker positionings, or are they conveniently just plonked on any old shelf in you den ?. Dan.
 
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Stevo, I would add to the speaker positioning discussion that resonant cavities distributed throughout the house (ie bedrooms, WC, pantry, cupboards etc) alter optimal speaker positioning. The tuning that works with all doors/entries closed changes when any door of the house is ajar.....and is detectable from anywhere within the house and outside the house.

Just sayin' in case this was missed in the video/papers.

Dan.
 
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Stevo, I would add to the speaker positioning discussion that resonant cavities distributed throughout the house (ie bedrooms, WC, pantry, cupboards etc) alter optimal speaker positioning. The tuning that works with all doors/entries closed changes when any door of the house is ajar.....and is detectable from anywhere within the house and outside the house.

Just sayin' in case this was missed in the video/papers.

Dan.

Um.............. The way this process works is that whatever is is, re. the room the speakers are in. One thing that Rod Tomson used to emphasis is that rooms that have openings into other parts of the house are really good as they let the sound out of the room. Closed rooms keep the sound in the room to bounce around to oblivion and decay. There is often a bit of discussion in forums about properties of the listening room. Rod used to talk in quite different terms about a room for music. He would emphasis things like room comfort, ability to have conversation without echoes. He would also say that he thought that dedicated listening rooms were generally the worst. Though I must add that most of his high end clientele probably had dedicated listening rooms, though of course I wouldn't really know
 
Um.............. The way this process works is that whatever is is, re. the room the speakers are in. One thing that Rod Tomson used to emphasis is that rooms that have openings into other parts of the house are really good as they let the sound out of the room. Closed rooms keep the sound in the room to bounce around to oblivion and decay.
The trick is to have an open pathway from the listening room that is long, like a hallway. However if there is a room that opens to that hallway a resonant cavity results, and this can be audibly good or bad. What I am wanting to impress is that house conditions (ie which doors open or closed etc) needs to be decided before the placement optimisation begins. To add further complication it may be found that particular house 'settings' can enable better optimised positionings than other house settings, and changing house conditions will change the sound of any particular positioning.

There is often a bit of discussion in forums about properties of the listening room. Rod used to talk in quite different terms about a room for music. He would emphasis things like room comfort, ability to have conversation without echoes. He would also say that he thought that dedicated listening rooms were generally the worst. Though I must add that most of his high end clientele probably had dedicated listening rooms, though of course I wouldn't really know
Yeah closed heavily damped listening rooms are more like theaterettes......fine enough for tv/video but too dead and too isolated for good sound. I live in an almost silent area except for nature/natural sounds and I generally/usually like to have the back verandah door open to allow some of these natural sounds in as reference plus it just feels better than being in an isolated 'cell'. When I sit 'in the chair' and run the system at full tilt I do ensure to close all doors and windows and quickly redo speakers and sub fine positionings, works for me.

Dan.
 
Another possible reason is that the average listener/enthusiast succumbs to external factors like room decor WAF etc and is denied the possibility of optimal positioning.
How many here employ the linked/discussed method to optimise speaker positioning ?.
My woofers are U-frame and separate from my wideband mains which could make using this method tricky? However, I'm able to position the mains anywhere easily when listening and I found nearfield to be best so far.

The woofers have been placed to give a smooth response in my listening position with minimal EQ. Is the bass response using the discussed method also smooth when moving around?
 
I am still trying to understand how moving a speaker 2 mm this way or that can have an effect on say the bass frequencies where the wave length is maybe 10 to 15 meters. Even at 20 kHz, the wavelength is almost 10x. 8 to 10 feet apart (maybe more if the room is bigger), position youself equidistant from the speakers, follow the guidelines (rear wall reinforcement or not etc) and you should get a stirling result.
 
My woofers are U-frame and separate from my wideband mains which could make using this method tricky? However, I'm able to position the mains anywhere easily when listening and I found nearfield to be best so far.

The woofers have been placed to give a smooth response in my listening position with minimal EQ. Is the bass response using the discussed method also smooth when moving around?

Okay........................
The Mantra of Master Set, Sumiko Method, Rational Speaker Set Up, whatever is...........................
ANY SPEAKER ANY ROOM
 
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I am still trying to understand how moving a speaker 2 mm this way or that can have an effect on say the bass frequencies where the wave length is maybe 10 to 15 meters. Even at 20 kHz, the wavelength is almost 10x. 8 to 10 feet apart (maybe more if the room is bigger), position youself equidistant from the speakers, follow the guidelines (rear wall reinforcement or not etc) and you should get a stirling result.

Don't try to understand, just do it.
If you watched the video the basic instructions are all there and you can follow them.
I can only add that the distinctions in the bass are pretty subtle and may be hard to pick up. Dialling In makes it sound simple like turning a dial. It's not simple and easy to pick up.
 
I am still trying to understand how moving a speaker 2 mm this way or that can have an effect on say the bass frequencies where the wave length is maybe 10 to 15 meters. Even at 20 kHz, the wavelength is almost 10x. 8 to 10 feet apart (maybe more if the room is bigger), position youself equidistant from the speakers, follow the guidelines (rear wall reinforcement or not etc) and you should get a stirling result.

I think it is due to the multiple eigentones of the room.
 
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