Pundit
Post by peter0c on Jun 27, 2023 10:03:17 GMT 12
A few photos were taken for the forthcoming updated Facebook page. We took a break from music whilst the rain was thundering downand Richard talked about his new Oswald Mills K4 turntable. Voluntary societies like the AAS and indeed Dark Lantern only survive if members contribute to what is on show. There is not much sense staying home or lamenting that there is 'nothing in it for me'. What is offered is what members contribute. The Outer Link bus service passes your home and the venue RDM. No excuses next month when I am demonstrating a First Watt F1 current amp with Toshiba JFet output devices!
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Pundit
Post by peter0c on Jun 27, 2023 11:20:31 GMT 12
As a side issue, the AAS has reorganised the speaker placement in the small hall hired for the occasion. This rectangular hall (10 metres wide and about double that in length) has proved problematic because of unwanted reverberation. So instead of plugging the ports of the house Q Concept 500 speakers it was decided to 'use' the room (i.e. identify the null spots) rather than fight against it. The following formulae from George Cardas and Jim Smith achieved a good result. 1) George Cardas’ Speaker Placement Recommendations (https://www.enjoythemusic.com/magazine/manufacture/0602/cardas.html) The distance from the centre of each tweeter to the adjacent wall should be .276 times the width of the room. The distance from the centre of the tweeters to the rear wall should be .447 times the width of the room. These calculations are based on the Fibonacci sequence of numbers (https://en.wikipedia.org/wiki/Fibonacci_sequence) resulting in ‘golden ratios’ such that any one dimension is not a function of any other dimension. This minimises the reflective nodes (reverberation) created within a room by the speakers below what is known as Schroeder’s Frequency. www.soundandvision.com/content/schroeder-frequency-show-and-tell-part-1; www.soundandvision.com/content/schroeder-frequency-show-and-tell-part-2 This was discovered to be up to 300 hz in a large room (100-200 hz in most domestic situations) and is just below the frequency (i.e. 330 hz) at which typically half the electrical power of recorded music is below and half is above. 2) Jim Smith’s Speaker Placement Recommendations (www.getbettersound.com) The distance between the centres of the tweeters should ideally be .83 times the distance from each tweeter to the listeners left and right ear respectively. Put another (and easier) way, the distance from the listener’s left and right ear to respectively the left and right tweeter should be 1.205 times the distance between the left and right tweeter. The latter figure is simply the inverse of the former and is also recommended by Wilson Audio. Smith J (2008), Get Better Sound, Quarter Note Press, Cumming, GA
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Post by michaelw on Jun 27, 2023 20:03:49 GMT 12
Is this the AAS FB age ? www.facebook.com/akaudiosociety/Last entry was April 26 2017 ? Everyone has magic numbers for speaker setup
I use Pearson's Rule of the Thirds - easier calculations
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Pundit
Post by peter0c on Jun 28, 2023 12:49:48 GMT 12
Yes Michael that is the AAS Facebook page, unadorned since 2017. That is what happens when members of voluntary organisations individually decide that someone else should be doing it. Fortunately AAS members meet once per month which keeps things going but this doesn't do much to attract new members. This is why I started pacing the AAS meeting schedule on Dark Lantern. Think what would happen to Dark Lantern if members individually decided that it is for other members to make postings in order to make it interesting and viable?
Not everybody has magic numbers for speaker setup - dare I say it (wash my mouth out with soap) even some Dark Lantern members might not have come across them. AAS didn't and instead used trial and error followed by more error to the point that they were thinking of finding new premises. The Cardas and Smith magic numbers worked wonderfully well as do the current $65 per meeting hire costs. Because the width of the hall is 10 metres, the calculations weren't that hard.
Pearson's rule of three (which will be well known to photography clubs) might also have worked. If all else fails asymmetric speaker placement (i.e. one speaker slightly offset from the calculated 'optimum' placement) might be the last resort.
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Post by michaelw on Jun 28, 2023 15:57:36 GMT 12
Same with Wellington Audio Club.
Club newsletters come and go like the tide but without the regularity.
Those with long memories will recall the WAC newsletter was the genesis of Mike Jones' AudioEnz magazine.
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Post by Citroen on Jun 28, 2023 16:48:41 GMT 12
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Post by RdM on Jun 30, 2023 23:03:59 GMT 12
A few photos were taken for the forthcoming updated Facebook page. We took a break from music whilst the rain was thundering downand Richard talked about his new Oswald Mills K4 turntable. Voluntary societies like the AAS and indeed Dark Lantern only survive if members contribute to what is on show. There is not much sense staying home or lamenting that there is 'nothing in it for me'. What is offered is what members contribute. The Outer Link bus service passes your home and the venue RDM. No excuses next month when I am demonstrating a First Watt F1 current amp with Toshiba JFet output devices!
I'm sorry I missed the event, and talk of the K4; -
I'd seen him earlier discussing it via YouTube I think, obviously a nice chap, and it would have been a privilege and pleasure to have been in the same room with him.
However, I'm still recovering from smashed teeth, concussion, and an underlying terminal condition. I get tired easily, and I just wasn't able to make it. I've missed a couple of amateur radio club monthly meetings too.
Actually the Outer Link nearest point for me would be Victoria St some 845m away, & the long way round.
I'd take a 22 something from near Grafton Bridge, half the distance and more direct, less time. If I'm up for it.
I'm glad to read that the speaker-room interactions have begun to be addressed.
As for jfets, I find I have 3 pairs of Sony 2SK60 & 2SJ18, two pairs with same codes. I should upload pics in a separate thread. With test results. Almost unobtainium?
Looking at the heatsinks required and all for a few watts, I'm not sure that I'd want to continue with them, even with 91dB speakers. Or, really, whether I have time to. Although construction is possibly simple enough, and I do have saved chassis and heat sinks ...
So maybe I'll document them and put them up for sale. Or should I try them out?
What do you reckon?
Cheers, no problems!
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Pundit
Post by peter0c on Jul 1, 2023 12:54:19 GMT 12
RdM here is a link providing circuit for your Sony V-FETs, the precursor to the wonderful SIT device found only in First Watt SIT 1 (100 made), SIT 2 (100 made) and SIT 3 (250 made). www.firstwatt.com/pdf/art_diy%20sony%20vfet%20os2.pdfThe boards are available from DIYAudio and complete kits were made available last year through a 'lotto' draw. The First Watt F1J and more recent F8 use NOS Toshiba 2SJ74 P channel Jfets and new (now also unobtainable) SemiSouth R100 SiC power J-FETs.
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Pundit
Post by peter0c on Jul 2, 2023 12:49:21 GMT 12
A bit more on speaker placement. I followed up a link on one of our forums which led to another about room treatments, namely the AMROC tool. amcoustics.com/tools/amroc?l=365&w=321&h=520&re=DIN%2018041%20-%20Music It is a wet and windy Sunday here in the land of Auck and I presume in much of the country. So pull out your tape measures and record your listening room dimensions (mine is a standard kauri villa living room with a bay window 5.28m long, 3.65m wide and with 3.21m ceiling) and enter into AMROC. The results can be interpreted via amcoustics.com/articles/roommodes. The calculations informed me that my internal volume was a 61 cub metres and that the room Schroeder frequency was 198hZ at .6 sec with a critical distance of .57m. My music certainly sounded better from knowing this (!) but I need help in understanding the graphs and recommendations. Has any one else had experience with this tool? .
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Post by michaelw on Jul 2, 2023 14:17:12 GMT 12
I went to the same link mentioned by Robert Harley, plugged in my room dimensions and also got back numbers that I don't know what to do with... I think my system sounded better too
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Post by Citroen on Jul 2, 2023 15:55:29 GMT 12
Now what?
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Pundit
Post by peter0c on Jul 2, 2023 21:30:24 GMT 12
I blame Michael. It was his blog on Robert Harley's listening room from which I got the AMROC link. I can see that I am about to have a sleepless night worrying about my fundamental resonance.
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Post by michaelw on Jul 2, 2023 21:55:57 GMT 12
Good audio is founded on paranoia
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Pundit
Post by peter0c on Jul 2, 2023 22:56:12 GMT 12
And jealousy.
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Post by RdM on Jul 3, 2023 23:05:04 GMT 12
RdM here is a link providing circuit for your Sony V-FETs, the precursor to the wonderful SIT device found only in First Watt SIT 1 (100 made), SIT 2 (100 made) and SIT 3 (250 made). www.firstwatt.com/pdf/art_diy%20sony%20vfet%20os2.pdfThe boards are available from DIYAudio and complete kits were made available last year through a 'lotto' draw. The First Watt F1J and more recent F8 use NOS Toshiba 2SJ74 P channel Jfets and new (now also unobtainable) SemiSouth R100 SiC power J-FETs.
Thanks. I'd seen and read the earlier Sony (V-Fets, of course!) articles but hadn't noticed those recent updates. All downloaded now.
If I were to do anything with them, I'd like to prefer a stereo PP circuit version. But maybe I don't have time anyway, so they could go to someone else.
I see on diyaudio a thread on F5T. What circuits for PP?
But again I have to move soon, 3-4 months, so I'll be lively doing that, packing things into boxes, not undertaking any new work!
Cheers
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Post by RdM on Jul 3, 2023 23:20:04 GMT 12
Recently viewed and really interesting interview talks in Munich with Richard Krebs, on the K5 turntable development saga. Wow.
The 2nd part even more so.
Are we waiting for Part 3?
I hadn't even realised he was NZ based.
Great talks.
Thanks! ;=})
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Post by michaelw on Jul 4, 2023 10:59:34 GMT 12
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Post by RdM on Jul 5, 2023 21:00:46 GMT 12
Are we waiting for Part 3?
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Post by Citroen on Jul 5, 2023 21:23:55 GMT 12
More like Part 1 on repeat!
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Post by RdM on Jul 5, 2023 22:46:36 GMT 12
More like Part 1 on repeat! Well, I can understand and accept some repetition, different or some same swirling crowds in the audience over 3 days.
It is what it is;-
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Post by michaelw on Jul 6, 2023 11:17:41 GMT 12
Someone should have moved the plonker who continually stands in front of the camera.
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Pundit
Post by peter0c on Jul 6, 2023 14:11:04 GMT 12
It is the same person who stands in front of the speakers they are interested in and talks loudly about them (or the amplifier driving them) instead of listening.
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Post by Citroen on Jul 6, 2023 16:00:03 GMT 12
Seems like every demo room has one of them!
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Pundit
Post by peter0c on Jul 7, 2023 11:05:26 GMT 12
Every audio society has at least two. A natural law of the universe.
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Pundit
Post by peter0c on Jul 19, 2023 13:26:58 GMT 12
FYI "AAS JULY MEETING - MONDAY JULY 24 Softball Clubrooms, Cornwallis St, St Lukes This month’s meeting features a presentation by Andre Gil of ‘AG Lifter’, audio isolation specialist, principally isolation racks. As he might not be terribly well known to some of our members, I copied some info from his website. “AG Lifter is powered by AE Gil Technologies, a 100% Kiwi Owned and Operated engineering-based company, born of over 35 years’ experience in industrial engineering, design and automation, with engineering capabilities extending into category one motorsport. Andre and Vanessa Gil, Company Directors and avid music lovers, created AG Lifter out of passion for high quality audio reproduction and New Zealand made products by like-minded Kiwi Companies. AG Lifter Mk 1 Isolation Foot was born, on completion the proto-type was tested and performed favourably. This was the driver toward understanding the problems present in the Audiophile’s listening environment. Now we have arrived at Mk 6, this product alone, went through over 40 changes from its conception. Through extensive research and development, we reached our goal.” “AG Lifter customers describe the sound of our Isolation Racks as: Lower Noise Floor Tuneful & Melodic Energetic & Lively Natural & Organic Better Rhythm & Timing” Their motto is “ MORE MUSIC, LESS NOISE” Andre’s website is aglifter.co.nzWe hope to be able to run the Oppo front end on our standard gear support, and on one of Andre’s racks. Should be interesting – see you there. Sec"
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Post by Citroen on Jul 19, 2023 13:46:17 GMT 12
AG LIFTER DULCET 20 GOLD ISOLATION FEET 4 PACK $2,996.00
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Pundit
Post by peter0c on Jul 19, 2023 13:54:11 GMT 12
Those go under your Lazyboy chair Citroen to prevent excess snoring finding it's way into your system.Apart from that here is an explanation from Nirvana Sound, an Australian retailer.
Sometimes the most amazing products are born when a ‘perfect storm’ of conditions comes together at the right time and place. In the case of the superb AG Lifter range of isolation devices, we can be thankful that the creators happened to have both a passion for music and decades of experience in mechanical engineering, including solving resonance issues across a broad spectrum of industrial applications.
AG Lifter is powered by AE Gil Technologies, a New Zealand based engineering company with over 35 years of experience in industrial engineering, design and automation and with engineering capabilities extending into category one motorsport. Company Directors Andre and Vanessa Gil are ‘mad audiophiles’ and understanding the negative effects that resonance has on the performance of hi-fi equipment, one day these avid music lovers created an isolation device to improve their enjoyment of their audio system.
After a long period of research, development and testing which saw 40 changes to the initial prototype, the first batch of AG Lifter isolation feet were taken to a prominent audio dealer in Christchurch, New Zealand where they were auditioned against some of the world’s most renowned established brands. The results were so conclusive that orders were placed and AG Lifter was officially born.
AG Lifter audio isolation products are designed to be a mechanical diode which stops resonance from entering audio components in both directions, both externally but also internally. It is a general misconception that harmful vibrations only enter your audio equipment externally from elsewhere in your room. In fact, most harmonics are actually produced internally by your audio equipment. Factors such as transformers, power supplies and electronic components resonate to the frequency that music signals enter components on your rack. Audio components micro-phonically pick up these frequencies and repeat them, causing reverberations. This can be heard through your speakers as a ghosting sound after the last note has been played. In other words, the presence of resonance in a music system can result in a smearing, or lack of clarity of sound.
An often-repeated complaint from many audiophiles is “my system sounds too harsh or bright and it ruins my listening experience”. There are a number of factors that may influence components or combinations of audio equipment to inherently sound this way in your listening room. However, quality mechanical audio isolation systems can go a long way to help with this, removing the harder or harsher edges from your listening experience. Together with combinations of careful system placement and cable choices this problem can be greatly eliminated.
The addition of AG Lifter isolation devices can have the following effects on a system:
Quieter background, lower noise floor An opening & expanding of the musical presentation A deeper, tighter bass performance with increased definition More ‘organic’, or natural textures An increased weight and scale to the sound stage An increase in detail across all frequencies
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Post by michaelw on Jul 19, 2023 15:35:01 GMT 12
Stereo rack comparison
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Pundit
Post by peter0c on Jul 25, 2023 11:28:33 GMT 12
Alright I will admit it. I was wrong and am sorry. Very very wrong and very very sorry. I am of course talking about the "AGLifter (Audion Isolation Specialists) which was demonstrated last night at the AAS. My sin was in entering the AGLifter for the weekly DL "sweet tunes or crack pipe" award, chiefly because of the price and my well-practiced cynicism about miraculous new products. However this one from Andre Gil really works, an opinion shared by all 20 or so people attending. We first listened to a tune (lousy music but all is forgiven) through the AAS system (Oppo 105, Krell K300i integrated amp and Q Acoustic Concept 500 speakers) with the CD player and amplifier sitting on the usual softball club two-level light and rigid table thingy, the sort of thing that patrons typically lean on in RSA and Cossie clubs across the country, whilst drinking and watching Sky Sports. So nothing special but we thought good enough. (In retrospect we possibly also should have tried the equipment simply sitting on the club-room's concrete floor to test out whether this table was a contributing to isolation problems). Both pieces of equipment were then placed on an AGLifter support and the track repeated, followed by a wider selection of music. The improvement was immediately obvious and not at all subtle. That everything sounded less congested is probably the best summary that I can give. Holy crap, humble pie it is for me at lunchtime. I hesitate to say what the price is - well I will say, $3kish for the single amplifier platform and up to $10k for the two, three or four level models. Best you see for yourself on www.aglifter.com. I am starting a givealittle page for me alone, so please give generously. Please.
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Post by michaelw on Jul 25, 2023 12:02:51 GMT 12
Given the baseline of Linn-style light and rigid table, results could only go up. One can only imagine the possible improvements wrought by replacing all that steel and acrylic.
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