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Qwin
19-06-2017, 11:39
Had a low key meet at mine on Sunday, Peter (Petrat) and Gordon (Halfwaytree) dropped in.

Peter was in the area and suggested a get together, it turned out to be a great session.



http://www.jkwynn.co.uk//Project_Images/Tech3/Tech3_037.jpg

Gordon brought a test LP that worked with an App on his tablet. It showed my Turntable had remarkably low wow/flutter and that the speed was very accurate, which being based on a Technics SL-1200 motor assembly is no great surprise, but nice to have confirmed after all my modifications.




I've just completed building a fully discrete tracking power supply for my Pro-Ject Phono Box RS, replacing the tiny wall wart supply.(Still needs painting Black)

http://www.jkwynn.co.uk/Project_Images/Pro-Ject/Proj_08D.JPG

http://www.jkwynn.co.uk/Project_Images/Pro-Ject/Proj_09A.JPG

It's a Sigma 22 kit available from glassjaraudio.com and designed by AMB Labs. I basically copied a project by killie99 on wigwam and added my own twist on the packaging. Find it here: https://hifiwigwam.com/forum/topic/122897-off-board-linear-power-supply-for-project-phono-rs/


I was more than chuffed with the improvements the new power supply brought.


That was, till Peter dropped his EAR 912 pre/phono into my set up.

https://www.stereophile.com/images/1205ear139389.jpg

I know it's from a completely different price point, costing many, many times more than my Pro-Ject gear, so a direct comparison is a bit unfair, but boy did it sound good. A level of dynamics, transparency and mid range detail I've not had from my system and something to work towards achieving.


The positives I got out of it, were that my TT set up is even better than I had thought and capable of working with top performing gear.



http://www.jkwynn.co.uk////Project_Images/Yam/yam_25.jpg

Also just how good my Nakamichi AV power amp is, when fed a good signal.





I think the consensus was that my DIY active speaker set up is certainly capable of holding its own at this level.

http://www.jkwynn.co.uk///Project_Images/SAP/sap_14C.JPG

I have lots of other things I want to try with the speakers, but I can do this with confidence, knowing that I can always come back to this current point, which works so well.

My Pro-Ject based set up is good, very good at it's price point, but I just had a glimpse of what lies beyond and I am hooked. :D

Great day guys, must do something similar again.

Apologies for using old pictures, but no one got a camera out and I know how you all like pictures. :)

JohnJo
19-06-2017, 11:48
Great post Ken, lots of nice photos to look at.

Very neat build on the PSU!

Peter, I love the way you're prepared to bring some of the best hifi gear around to share with others for the mutual enjoyment of all :cool:

Sounds like a great day.

brian2957
19-06-2017, 12:56
Nice one Ken . It's good to have an occasional meet of like-minded people . Good to see that you all enjoyed it .

I had a great at Ali Taits place yesterday , and made a few new friends into the bargain :)

I took a couple of snaps and will post them when I have the time .

Qwin
19-06-2017, 15:05
John - Yes, glad Peter went to the trouble of bringing the 912, which is a hefty piece to lug about, I learnt a lot from what we tried.

Alan - Looking forward to the low down on what you guys got up to at Ali's.

petrat
20-06-2017, 07:06
Yes, a really interesting day!

I'd agree with Ken's analysis. The diy turntable/arm/cartridge are top-notch, and I'd be hard-pushed to figure out how they could be improved, without starting all over again. The Nakamichi 5 channel power amp continues to impress (wish I'd never sold mine :doh:). The way that Ken has tuned the crossovers for his diy speakers is really spot-on for the room. The only potential improvement I could hear was that the bass drivers weren't quite of the same high quality as the ribbon tweeters and mid units .... I think I'd have preferred paper cones to give more 'texture' in the low bass, but Ken pointed out that the cost of decent ones might be a bit prohibitive. OTOH, Ken's next project is to do away with the analogue cross-overs and go fully active ... something which often raises the bar ime. That would also allow him to ditch the pre-amp, which I think we showed is a real 'bottle-neck'. With my pre/phono in, we heard the true potential of the rest of the system, and if I were in Ken's situation, I probably wouldn't even bother going active, and put the effort into building a really good diy pre and phono, as what we were hearing was really rather good :thumbsup:

Overall, I was truly inspired by what Ken has achieved so far ... high quality on a 'real-world' budget. Thanks to Ken and Gordon for a very pleasant day ... I learned a lot. Cute dog, too :D

drSM
20-06-2017, 10:55
Sounds like great fun at Kens
That tt looks intersting Ken.
Not being fmiliar with Technics DDs i was really amazed when a friend who had modded a 1200 demoed it for me and showed me the motor assembly and how precise the speed control was.
Re phonostages i too have heard what expensive ones can do (Pass labs in my case )
I thought you were going to use yr NS1000 s ( i followed yr thread re going active, until i couldnt understnd wht was going on ! duhh )
Cheers

Halfway Tree
20-06-2017, 13:07
The diy turntable/arm/cartridge are top-notch, and I'd be hard-pushed to figure out how they could be improved, without starting all over again.

I have to agree with Peter, here. That really is a very, very good turntable. Not only does it sound good it measures exceptionally well - the very low wow and flutter figures (better than numbers I've seen for a Rocksan TMS costing way, way more) show why it sounds rock solid with real drive. I should have taken a screen shot so I could post it here - they really were exceptionally good. In case anyone is interested I was using Dr Feikert's Platterspeed app together with a Tacet test LP.

As for Peter's EAR 912 - beautiful tonality - it pulled off that trick of warmth without losing any detail - I would have loved to listen to it for longer but had to leave early in the afternoon as I promised the family I'd do a Father's Day BBQ.

Another highlight of the day for me was the lunch - in one word - delicious!

All in all a great day with great company - thanks guys.

Gordon

Qwin
20-06-2017, 13:26
Shahrin - Hi, I struggle to keep up with all the developments myself.

Basically I am still doing lots of different experiments that will give me a direction and a final set of speakers.

I still have the NS-1000M which I took about as far as I could, these have a 3-way analogue active crossover based on the KMTech boards, but with some modifications.

My semi active project is what we used in this get together. This is a pair of Quad S-1 Bookshelf drivers, still using their passive midbass/tweeter crossovers, augmented by a pair of 12" Scanspeak bass drivers, the whole thing is pre filtered through an analogue KMTech 2-way active filter, set at 310Hz. Above 310Hz is fed to the Quad passive filter, below direct to the woofers.

My next move for this semi active set up, is to go fully digital active, using the Hypex DLCP system. I also want to try using the Yamaha Beryllium dome midrange in this set up. I have all the Hypex boards and power supply, I just need to create a lash up and try it out. When I can find the time that is.

In post #5 above, where Peter says "and if I were in Ken's situation, I probably wouldn't even bother going active," he means fully digital as the set up we were using was already partially active, though using analogue boards.

I have further plans to replace the Nakamichi Power Amp with Hypex UcD Amp modules built into the DLCP enclosure and my lay out accounts for these. I'm taking it one step at a time though and assessing each of the changes before moving on to the next.

My choice of bass drivers, in the Scanspeak 12" alloy cone, is a slight compromise.
Ideally, I would have liked a paper cone, as I like the sound they produce, but I couldn't find one that would go deep enough in a reasonable sized sealed box. Many will give deep bass in a ported enclosure, but end up with an F3 of 50 to 65Hz, dependant on model, in a sealed enclosure.
My room does not like ported and my locations limit the size of the cabinet, so 50 to 60 Litres sealed is pretty much set.
Also I needed a Bass driver that was flat up to about 1000Hz to integrate with the midrange.
The Scanspeak is basically a subwoofer, that will do F3 of 38Hz in a 55L sealed box. It is also flat up to 1000Hz, which is unusual for a sub unit. It is fast and deep, though with the alloy cone, maybe not quite as nice, in the texture department as a paper cone. (Though some might disagree about that).
In my smallish room which has a lousy shape, I manage to get remarkably deep, well controlled bass, even at fairly loud levels.

The Scanspeak bass ticks more boxes than anything else I could find from Seas, Scanspeak, Volt, Peerless, Morel, Dayton, SB Acoustics etc or at a reasonable price (Less than £600 pair).

I still have a lot of things I want to try, like an itch I have to scratch, but I'm in no hurry. :)

Qwin
20-06-2017, 15:00
Yes, it was a great day Gordon.
I will pass on your comment regarding the food to Pat.

Just noticed a typo by Peter - The Nakamichi is a 7 Channel Amp not 5.
I was using just 4 channels of this.

Qwin
20-06-2017, 15:15
That tt looks intersting Ken.


Check out my build project here: http://www.jkwynn.co.uk/Tech3_HTML/Tech3_Thumbs.html

drSM
24-06-2017, 02:34
site not found Ken

petrat
24-06-2017, 13:39
Works for me, Shahrin.

sq225917
25-06-2017, 07:25
Gents the platterspeed app is next to useless. It filters out a huge chunk of speed error as noise. You need a w and f meter and a known good test record, ie the German test standard one to really see into the speed stability.

Halfway Tree
28-06-2017, 09:00
Gents the platterspeed app is next to useless. It filters out a huge chunk of speed error as noise. You need a w and f meter and a known good test record, ie the German test standard one to really see into the speed stability.

That's a bold statement - can you explain in more detail, please. Do you have a comparison between the platterspeed app and the same TT measured with a W&F meter?

Qwin
28-06-2017, 09:10
site not found Ken

My hosting company have been changing servers so it might have dropped out for a while overnight here (link to my site).

Or do you mean the Hifiwigwam link?

They both are working for me.

drSM
03-07-2017, 00:30
My hosting company have been changing servers so it might have dropped out for a while overnight here (link to my site).

Or do you mean the Hifiwigwam link?

They both are working for me.

It works now Ken
Super project - what parallel tracking arm is that ?

i like wht u did to your td150 too

Qwin
03-07-2017, 05:58
Thanks Shahrin, its a Trans-Fi Audio "Terminator" Arm, find them here:

http://www.trans-fi.com/

RichB
03-07-2017, 12:06
Looks like a good get together.

Ken's system and turntable always a treat for the eyes and ears.

Qwin
03-07-2017, 12:13
Looks like a good get together.

Ken's system and turntable always a treat for the eyes and ears.

Thanks Rich, made some significant improvements this week by using the balanced inputs on my Pro-Ject Phono stage, which is a fully balanced circuit.

Also just pulled the trigger on an Aqvox 2Ci mkII which is supposed to be in a different league.

So my system might be different, next time you hear it. :)