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Post by karatestu on Feb 6, 2018 12:48:00 GMT
Hello I'm Stu.
I have been reading the forum for quite a while now and just decided to register and hopefully contribute. I found this forum via HFS (hope that doesn't go against me) and am a member of various other forums.
My hifi journey started in 1990 when I bought some Marantz electronics and Wharfedale speakers from Richer sounds. They stayed with me until 1997 when I bought Naim Nait3, CD3.5 and B&W P4 speakers. Still have the speakers and CDP although the speakers have been side lined since last year and the CD3.5 is hardly recognizable since I have modded the nuts off it and added numerous psu's.
Got a LP12 and Lingo in 2000 from a friend for £150. Still cant quite believe that I got it so cheap. Amp was upgraded to Nac72 with hicap and a pair of Nap140's. Nac 72 had all the boards ripped out except the internal phono boards and Avondale 821A preamp boards were added. Still use the 821A's but not in the Nac 72. Nap140's I converted to two mono amps. Then added Avondale minicap and NCC200 boards. I still use Avondale power amp boards but with new transformers and I have split off the front end and given them their own regulated psu's. Plus added two more identical mono blocks so that makes four all together. Naim cases and parts are in a cupboard now. Only Naim thing I have left is the modded CD3.5 and Aro tonearm.
LP12 got some attention too. Fitted a Naim Aro and a Lyra Argo cartridge. I have a Rubikon subchasis waiting to be fitted along with an Avondale Taps2 psu to replace the Lingo. Thinking of moving the motor position to 7.30 and have some Anologue Innovation "in sole" spring replacement thingies to try as well.
As the LP12 is the only serious TT I have owned I decided to open my horizons a little. Bought Les W's Pink Triangle PT1 with Alphason HR100S arm, Linn Asaka cart and Avondale PSU. Have not tried it yet. Along with that I now have a Pioneer PL-71 to try (after I have tightened the horizontal bearings a little). Much TT comparing fun to come.
I used my B&W P4 2 way transmission line speakers for 20 years without trying any others. I like them but wanted to explore other ways of doing things. After joining HFS I decided to make some sealed semi Omni speakers using the NVA drivers and making my own cabs. Turned out to be a hoot and I loved the semi Omni presentation. Then some larger cabs were added underneath with some 12" woofers which are doped of course with no crossover. Loved the improvement to the sound these brought. Not content with that I turned the big bass cubes into isobaric by adding another doped 12" woofer behind the original ones with equal volume given to both woofers. Tight bass here we come. They are still in prototype form waiting to be made into some cabs which are more aesthetically pleasing. I continue to listen to them every week.
Recent purchases have included (except for the PT1) NVA BMU, NVA AP20, NVA phono1, NVA TIS and NVA LS6. Needless to say, I like the NVA sound. Not sure where I am heading in the future. Possibly more NVA purchases and I will have to see which turntable I prefer when I have a shoot out between LP12, PT1 and PL-71.
Stu
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Post by Deleted on Feb 6, 2018 12:59:23 GMT
Hi Stu,
Sounds like you have a wealth of knowledge about Hifi components that you will be able to share with us all at TAS.
Your system also sounds very interesting, do you have pics?
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Post by ChrisB on Feb 6, 2018 13:46:36 GMT
Hi and welcome to the forum.
That's an interestingly evolved speaker system you have built and/or are currently building.
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Post by MartinT on Feb 6, 2018 13:59:05 GMT
Hi Stu and welcome to TAS! NVA make good kit and you have an interesting system there.
If I may, once you've heard a good DD turntable going back to belt drive is not easy!
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Post by karatestu on Feb 6, 2018 13:59:32 GMT
Yeah I know a few things and would be happy to share if any of it is useful. I am no electronics engineer and don't own any test equipment apart from a digital multi meter. Everything I have learnt is from selectively reading on the internet and trying things out for myself. I find trying things out myself to be the only way to really learn and listening to be the best way to assess changes (in my case the only way as I don't own a scope).
I think you will find the pictures of my hifi to be either fascinating, amusing or cause you to report me to the internet diy audio safety police. I am happy to post some if people here can prepare themselves for what they are about to see. All of my main system is in a room where no one else can access apart from me. I have no lids on any of the cases (except the NVA stuff) and there are wires going here and there. Bits and bobs (regulators, caps, additional home made psu's ) are soldered in at various points and I have made sure things are easily accessed for tinkering. None of it is really finished as there is always something else to try.
My family are not without music in the main living room however. I have a little NVA AP20 integrated, Cambridge audio CD5 and B&W CM1 speakers making everyone dance including my 8 year old son and 4 year old daughter. It really surprised me how bloody good this little lash up is and made me wonder (for a day or two) why I bothered buggering about with diy audio at all.
As a taster of the type of things I get up to, today I have removed the input coupling caps, zobel and output inductor from a couple of old (well respected) amp boards just to see what it would do (hopefully not oscillate and melt itself and the speakers). Well, with my low capacitance LS6 speaker cables it has turned out to be a revelation, completely safe (so far) and taught my a thing or two (that Richard Dunn has been saying for years).
Regards, Stu
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Post by ChrisB on Feb 6, 2018 14:18:49 GMT
We'd love to see the pictures and I shall prepare myself for any, and all, of the three potential outcomes!
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Post by MartinT on Feb 6, 2018 14:19:46 GMT
<holds breath>
I'm ready for the photos!
Removing input coupling caps can work provided it doesn't feed DC back into, say, a volume pot (which would become horribly noisy). It depends on the input circuit. Similarly, taking out the Zobel network is fine as long as the speaker cable doesn't cause instability. I've used LS6 and it sounds fine.
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Post by Deleted on Feb 6, 2018 14:23:46 GMT
Sounds intriguing, Stu. Looking forward to the pics.
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Post by karatestu on Feb 6, 2018 14:31:03 GMT
<holds breath> I'm ready for the photos! Removing input coupling caps can work provided it doesn't feed DC back into, say, a volume pot (which would become horribly noisy). It depends on the input circuit. Similarly, taking out the Zobel network is fine as long as the speaker cable doesn't cause instability. I've used LS6 and it sounds fine. Thanks Martin, The pre amp as I have it at the moment is an active stage which sits after the volume pot - so hopefully removing power amp coupling caps has not done anything bad. I can not hear any down sides as yet. I have been monitoring the power amp heat sinks carefully since removing the zobel and inductor and they are fine so far. There are no audible oscillations and if there were any inaudible ones then the heatsink shoud get hot - that is my understanding any way. |
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Post by karatestu on Feb 6, 2018 14:54:19 GMT
Hi and welcome to the forum. That's an interestingly evolved speaker system you have built and/or are currently building. Hi Chris, Yes the speakers evolved by accident really, well in the beginning they did. I bought a pair of 70's Marantz, 12" woofer, 3 way jobbies off ebay for peanuts. They arrived damaged so needed some work. I intended to do plain and simple "Doc mods" to them (see HFS) - remove xovers, dope drivers, cap & resistor on tweeters, remove wadding, steel line etc etc. The mid drivers were shagged so I decided to purchase the drivers RD uses in his cubes plus a big 12" woofer. They arrived ready doped but the mid and tweeter would not fit in the Marantz cut outs. A bit of work was needed and my interest was aroused in the semi Omni design that I read about at HFS. So, I made a little pair of cabs to house the doped 5 1/2 inch mid/bass and the visaton tweeter. I made everything from scrap bits of wood from the family farm. As I wanted to compare semi Omni to point & squirt I made two cut outs for the woofer - one on the front below the tweeter and one on top of the cab to try semi Omni. I made a thick aluminium blanking plate to cover the woofer hole that was not in use. Well my curiosity got the better of me and I decided to try semi Omni first. Well I was so bowled over by the experience that I did not bother to try the point & squirt option. I still had two 12" woofers doing nothing so these went in the Marantz cabs as all the other holes were blocked and there is LOADS of steel lining inside. I had trouble moving them. Little semi Omni cabs were placed on top of the larger Marantz cabs and that brought the tweeters up to ear level. At the time I did not factor in that the 43L volume of the Marantz cab would be too little. Turned out the bass was a bit over powering and a little flabby. Tried to pad the bass driver down but I was still not happy. So I decided to make some larger bass cabs (again out of old ikea furniture) of around 85L internal volume. Tried them in these bigger cabs and the result was awesome in every way. Never having had a driver over 6.5" my eyes (and ears) were well and truly opened. I lived with them like that for a while but the prototypes are not very aesthetically pleasing being thrown together from junk with no thought to tidiness. They were just for proving the designs worked, which they did. I thought of ways in which I could make the woofers work in the Marantz cabs and the only way was to go isobaric. RD uses isobaric loading in his cubix designs and raves about them, so I thought if it is good enough for Richard then it is good enough for me. I adapted my big bass cubes to give each driver the same volume as according to RD this us the right way to design isobaric speakers. Tried it and my lower jaw dropped to the ground and stayed there for quite a while. So whilst the design has been proven (to me) I still have some work to do to make some proper, pleasing to the eye cabinets that my wife will give house room to. I have been side lined though by messing about with amps, CDP and turntables. Stu |
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Post by karatestu on Feb 6, 2018 14:57:04 GMT
Hi Stu and welcome to TAS! NVA make good kit and you have an interesting system there. If I may, once you've heard a good DD turntable going back to belt drive is not easy! I have never heard a DD in my system and so am bracing myself for the result. The PL-71 is quite well respected and so should be in the "good" category. We are all different though and I am just hoping I don't prefer the Linn. I could live with the PT1 winning. Stu |
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Post by karatestu on Feb 6, 2018 15:41:11 GMT
 I don't think this pic is going to be visible as it is not to me when I try to preview it. I ended up deleting a bit off the end of the link code - something to do with redirects. Anyway I can now see the picture  This is the view in side one of my cubic bass cabs. I have added some thin strips of wood which I attached the rear baffle to which has another 12" woofer in it.  Another pic showing the rear baffle inserted and the associated wiring. I only had the back panel to attach then I was good to go. More pics to follow. It's pictures of the electronics where things get a bit hair raising. |
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Post by karatestu on Feb 6, 2018 15:59:15 GMT
Well, I cant work out how to put pics up hosted on my own website. Never had a problem with other forums.
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Post by julesd68 on Feb 6, 2018 16:18:51 GMT
Hi Stu and welcome to TAS! NVA make good kit and you have an interesting system there. If I may, once you've heard a good DD turntable going back to belt drive is not easy! I have never heard a DD in my system and so am bracing myself for the result. The PL-71 is quite well respected and so should be in the "good" category. We are all different though and I am just hoping I don't prefer the Linn. I could live with the PT1 winning. Stu I had a PL-71 for a while - very good deck indeed and there's not much you can do in terms of upgrades, which is great for some and not so great for others ... |
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Post by julesd68 on Feb 6, 2018 16:22:31 GMT
If I may, once you've heard a good DD turntable going back to belt drive is not easy! This of course is heresy. Expect the harshest sentence Martin ...  |
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Post by MartinT on Feb 6, 2018 17:31:25 GMT
<hides>
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Post by MartinT on Feb 6, 2018 17:33:37 GMT
Well, I cant work out how to put pics up hosted on my own website. Never had a problem with other forums. Give us a full URL to the photo (ending typically in .jpg) and we'll show you how. |
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Post by karatestu on Feb 6, 2018 17:53:30 GMT
Hi Martin,
If you look further up the page (i edited an earlier post) i managed to do it by deleting a bit off the end of the link text.
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Post by sq225917 on Feb 6, 2018 18:06:10 GMT
hair raising pics of NVA, that'll be a first...
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Post by ChrisB on Feb 6, 2018 18:14:43 GMT
Simon, please leave your squabbles from other forums at the door.
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