Jump to content

Ittaku

Amateur OB speaker builder and his ARC based digital system

Recommended Posts

16 hours ago, andyr said:

I was interested to read your comment "this is probably a function of just too many similar sized caps in parallel".  I had always thought it was a good idea to use multiple same-value caps, rather than a biggie and a little ... but you're saying I thought wrong?

Actually I had another thought about this. The earlier experiment was 3uF of PP+tin foil and 0.68uF of PE+tin foil. The later experiment (with only the one Mundorf) had 13uF of PP+tin foil and 0.68uF of PE+tin foil. Perhaps the problem is that the PP+tin foil aren't what's making the sound better at all but it's actually the PE+tin foil which are the best sounding caps I've ever had (prior to the copper paper in oil), and adding more of the PP+tin foil ones was what was making it worse. Either way, the Mundorf sonic signature was not going away which was the point of testing less Mundorf.

 

I'll test this theory by trying ONLY the 0.68 as bypass to... every other combo.

Edited by Ittaku

Share this post


Link to post
Share on other sites

Unhappy with the Mundorfs and surprised by the sound of the cheaper miflex by comparison, I've got yet another shipment and I'm going to use them to the midrange and woofer instead now, and bypass with a PIO to the midrange.

 

vS8OKoG.jpg

Share this post


Link to post
Share on other sites

So I've wired in the miflex caps and given them a good 24 hour burn in and listening to. I much prefer this sound to the Mundorfs I had there. It is a little less detailed "softer" sounding but much more pleasant on the ears and not fatiguing. Trying them directly that was obvious already, but putting in the 1.5uF bypass cap separately had yet another soundstage improvement, much like it did on the tweeter! It's like the midrange stage depth has moved back to join up that of the tweeter and make the air around instruments just seem more natural rather than just air for air's sake. So the whole sound stage is now focussed at a greater depth, like moving a few rows back in the auditorium (I've always had an extremely forward sound stage, like row D). It added a degree of delicacy too that was never there in the midrange. I love this sound. This is interesting because according to the humblehomehifi review, the plain miflexes which are the bulk of the capacitance, should have a "forward sounding midrange" but that's not remotely what they sound like to me. However, he was using them in a different application to mine so perhaps they behave quite differently as high power low voltage crossover caps. It's also interesting that the Mundorfs had a quality to the sound that I didn't like that reminded me of what I didn't like about the Chord Dave in my system. Perhaps it's very easy for my speakers to start sounding on the hard glarey side, and both of these quite renowned  components did that here, and it just needs that little bit of extra softening or warmth. Unusual given the tube pre+power amplification, but then again, modern ARC SE amps are not remotely lush and warm sounding, and the supratek preamp with the valves I have in it is also quite neutral. Either way, I'm extremely pleased with the sound of the midrange now.

 

The main caps on the tweeter are apparently due to come in from back order in October, so that will be the next - and probably final - change to the crossover components. I'm curious to see how much better it will get there.

 

The next experiment is to replace the internal wiring now that I've found what fits all the requirements I've always been looking for in internal speaker wiring. I've ordered some Neotech speaker cable which is four OFC flat strands sheathed in teflon:

https://www.hificollective.co.uk/wire/neotech-rectangular-speaker-cable-nemos-5080.html

Almost solid core, no skin effect, no proximity effect (unlike litz wire), very low capacitance, decent overall gauge (for internal wiring) and good quality copper. This is close to the holy grail for what I've always been looking for, without anything extra that I don't like, or haven't heard improvement with (like silver or silver coating, shielding, 6Ns copper, UP-OCC etc.)

 

I also ordered some of the Neotech interconnect wire to see what happens if I make up my own interconnects with similar qualities, plus shielding (for balanced interconnects):

https://www.hificollective.co.uk/wire/neotech-rectangular-interconnect-cable-nemoi-5220.html

Share this post


Link to post
Share on other sites
Perhaps it's very easy for my speakers to start sounding on the hard glarey side


I would have characterized the response curves posted previously as sounding ‘like that’ - but it’s impossible to be sure without seeing more charts, as one may not show the full story (eg 10 degree horizontal angles, or similar)

Did you ‘redo’ the DSP correction for each set of caps? (I wouldn’t have thought so)... but if you did, was there much change?

Share this post


Link to post
Share on other sites


These guys arrived today. Speaker rewiring is going to be a lot of work so I might try the interconnects first. Speaker wiring on top, interconnect at bottom.

 

h9YZ0tO.jpg

Share this post


Link to post
Share on other sites
24 minutes ago, Ittaku said:

These guys arrived today. Speaker rewiring is going to be a lot of work so I might try the interconnects first. Speaker wiring on top, interconnect at bottom.

Apologies if you have listed it earlier - but where did you purchase the NeoTech wire from - thanks

Share this post


Link to post
Share on other sites

Still busily wiring up the interconnects. Unfortunately the cable doesn't fit easily into the neutrik XLRs I bought so there's quite a bit of grunt work and making everything fit. Will post more on my findings once I have replaced DAC to pre and pre to power with them.

 

In the meantime, I actually asked Carlton Audio Visual way back when the ARC Ref 160Ms were announced about auditioning them in my system. They still haven't actually hit our shores here, but they promised I would get to listen to them once they had them and had a pair run in. Meanwhile, stereophile just published their review of the 160Ms (I have a digital subscription) and it's just making me even more anxious to listen to them. However, I don't just plan to drop them in and replace my 250SEs. Stereophile have never reviewed the 250SEs so from their end at least, I have no indication of whether the 160Ms are a worthy successor or not. The fact is that I have far too much power at the moment in the 250s, and if I can actually get improved sound, and still have plenty of power for my own speakers, it'd be a worthwhile change. I'm also keen to try their triode mode out as I often listen to a lot of music at quiet levels where lack of power would be meaningless, though it's interesting to hear the reviewer say the triode mode was basically the old warm coloured valvey sound that modern valve designs had pretty much gone away from. I still plan to audition them so watch this space.

Share this post


Link to post
Share on other sites


IMG_20180908_105129.thumb.jpg.1a0c053d1ef7473fa68051490bb6abe0.jpg

 

First impression of the new interconnects: Quiet. The background to everything is just blacker, and it's almost like the volume has been turned down slightly. Consequently there also appears to be less overhang to notes afterwards as well, without affecting the air around instruments itself. Otherwise, tonally they're virtually identical to the WyWires silver I had in my system. The only other notable difference was a little more focus in midbass notes. So the lack of overhang in notes is probably the only detriment so far that I can recognise. The big question now: Will there be any burn-in? I've thought that I've heard cables burn in myself, and if it is - as I theorise - due to a change in the dielectric of the cable after application of voltage over time, then with teflon dielectric in these cables it could be 400-800 hours before they burn in. That's kind of good and bad since it means it should improve substantially (I hope) but bad because it could take forever to get there. Either way, there's nothing unpleasant about the sound, and if it improves from here it can only be good. One very nice thing about working with teflon insulation, though, is the lack of it melting when you solder near where the insulation is stripped up to. I was very happy with my WyWires interconnects but they were a bit short, limiting where I could place my preamp, so I figured I'd try my hand at making my own longer first before just buying longer ones, hence why I've ended up here.

 

So I'll give these a good run for a week or so before resuming experimentation by changing the internal speaker wiring. I miss aspects of the megatwistlan (21 pairs of separately insulated solid cores) I had going to the tweeters when I changed to cardas crosslink 1S and am hoping to regain that with the flat neotech cable.

 

And now if you'll excuse me, I have to go listen to Beethoven's 9th to help burn them in.

Edited by Ittaku

Share this post


Link to post
Share on other sites

Had the new cables burning in "hard" with 2 days of max volume white noise to see if they changed. I didn't hear much change after the first day but after the second they've changed a lot. The sound has opened right up and the overhang of the notes has returned in force. If anything, the sound is bigger than ever now with instruments seemingly larger than life. Conversely, the "quiet" impression they gave when I first put them in has gone away. I suspect the quietness and lack of overhang to notes were actually one and the same thing. All good, and worth almost ripping my fingers to shreds trying to make them up. I guess this must be what the actual Neotech interconnects sound like, assuming their lowest range ones are the same cable (the Sahara sound like they are on paper) and should cost about $2k for a 2 metre pair. I made them up for a heck of a lot less :)

Share this post


Link to post
Share on other sites

The sound has been so good after the new interconnects that I haven't been tempted to do any more mods until more hardware arrives. It's hit one of those sweet spots where I can just listen and smile. Today I finally received notification that my larger caps for the tweeter have arrived and are being shipped, which means time for more tinkering. I have yet to rewire the internal wiring to the tweeter and midrange with the speaker cable - I need the new baffles to know how much wire to cut and where so I'm holding off on that for now. Still no new woofers though, thanks to the extraordinarily slow supply chain thanks to speakerbits 😕 My new baffle is still in the workshop, so hopefully that'll be ready soon. Exciting times, nonetheless.

Edited by Ittaku

Share this post


Link to post
Share on other sites

Finally these monstrous beauties arrived! My paper + polypropylene in oil copper foil Miflex caps for my tweeters.

 

IipLhdT.jpg

 

I've got my hand and a pen in the picture for reference to show just how monstrous they are. I also added a few similar valued caps I've used to comparison. The top right one is a multicap tin film and foil cap. Below it is my new "standard" cap from miflex which is a non-inductively wound metallised polypropylene in oil cap, and below it, one of the most popular affordable metallised polypropylene caps for crossover, the solen. If size alone is a determinant of quality, this is going to be something else. They each weigh 1.75kg and are as big as two coke cans.  Going to put them in this afternoon and give them a serious listening to. So far even just the small bypass value made a big difference, so I'm hoping for real magic.

Share this post


Link to post
Share on other sites


After almost a day of burning in, the top end change is nothing short of remarkable. The fleshing out of high frequency harmonics makes it sound like they're using different instruments. The sweetness added to the top end is incredible. It's like changing from paper cone tweeters to ribbons. It's interesting how the small value bypass made a completely different improvement to the sound than this one with the bulk of the signal going through it. The small value affected the air, focus and stage depth. This one changed the tonality. It's amazing how sweet a violin playing high pitched notes can sound, and yet even piano notes now seem to have harmonics that go on into the stratosphere. Then there's the peal of trumpets, the sonority of flutes, the clash of cymbals, the list goes on... Unlike when I put the Mundorfs in, there isn't a single thing to fault about the sound change, and it hasn't even been a day of burning in! It's a shame that it's impossible to meaningfully get 80uF of these in place for the midrange - it would be the size of a garbage bin and would break my crossover:driver cost rule - the crossover would cost almost 10x the cost of the drivers... To be honest, I'd always thought I hadn't made the most of these amazing tweeters, and now I finally do, though the high pass crossover to each tweeter costs as much as the driver it's feeding. Miflex, where have you been all my life?

Edited by Ittaku

Share this post


Link to post
Share on other sites
On 08/10/2018 at 1:38 PM, Ittaku said:

Finally these monstrous beauties arrived! My paper + polypropylene in oil copper foil Miflex caps for my tweeters.

 

IipLhdT.jpg

 

I've got my hand and a pen in the picture for reference to show just how monstrous they are. I also added a few similar valued caps I've used to comparison. The top right one is a multicap tin film and foil cap. Below it is my new "standard" cap from miflex which is a non-inductively wound metallised polypropylene in oil cap, and below it, one of the most popular affordable metallised polypropylene caps for crossover, the solen. If size alone is a determinant of quality, this is going to be something else. They each weigh 1.75kg and are as big as two coke cans.  Going to put them in this afternoon and give them a serious listening to. So far even just the small bypass value made a big difference, so I'm hoping for real magic.

WOW!  Crazy!  :lol:

 

Andy

 

Share this post


Link to post
Share on other sites
12 minutes ago, andyr said:

WOW!  Crazy!  :lol:

And you'll get to see - and more importantly hear - them in a couple of weeks :)

Share this post


Link to post
Share on other sites
11 minutes ago, Ittaku said:

And you'll get to see - and more importantly hear - them in a couple of weeks :)

Looking forward to it, Con!  :thumb:  As is Russ.

 

Andy

 

Share this post


Link to post
Share on other sites


Just got back from the hi-fi show. Feeling good about my system :)

Share this post


Link to post
Share on other sites

IMG_20181019_125906.thumb.jpg.d602abf408ae064840b5fb2a5571a5e0.jpg

 

Look what finally came! These are my 4x8ohm woofer variants of the current 4ohm woofers I'm using. These are courtesy of wagneronline who delivered, unlike speakerbits who I simply couldn't get through to. Interestingly from the email discussions I had with Monti at wagneronline, they said they're using a new supplier which means to me they dropped speakerbits. Anyway, alas I don't have my new baffles yet to start assembling the new design, so unfortunately those coming to audition my system on Monday won't get to hear them. The reason for going for 2 woofers instead of one was because of the substantial amount of room correction I use in the bass range, the current drivers can reach their excursion limits if I crank it up very loud, and I always want them operating in their optimal linear range. It's interesting because the woofers are rated to 350W, however it's very different when they're unloaded in an open baffle versus in a box. I really want to recreate realistic volumes for my Shostakovich symphony performances...

 

 

Share this post


Link to post
Share on other sites
On 24/05/2018 at 4:30 PM, Ittaku said:

I've been making my own custom speakers on and off for over 20 years and recently got inspired to start all over again with an open baffle design and all the latest scanspeak drivers, and upgrade pretty much all of my components. Apart from the baffle itself being only temporary still, I'm extremely happy with the final result. I set out to create something that should be very natural sounding and be scalable to recreate large scale symphonic works and organs. Here is the executive summary of how it looks, before I introduce the family members:

 

7nNZjLE.jpg

 

 

 

You call them open baffle?

 

This is an open baffle!  :P 

 

https://www.audioasylum.com/forums/MUG/messages/23/234213.html

 

Andy

 

Share this post


Link to post
Share on other sites
2 hours ago, Ittaku said:

I'll pay that...

 

Not sure you should, Con.  :)  I can't imagine why he needs so many drivers!  :o

 

Andy

 

Share this post


Link to post
Share on other sites
34 minutes ago, andyr said:

 

Not sure you should, Con.  :)  I can't imagine why he needs so many drivers! 

Uh yeah, I don't mean literally pay for it... Just acknowledging your comment.  That many drivers of the quality that I'm used to buying would cost about a million dollars... I think hes using the approach that school orchestras do, enough quantity will overcome the quality of each individual...

Edited by Ittaku

Share this post


Link to post
Share on other sites
23 minutes ago, Ittaku said:

Uh yeah, I don't mean literally pay for it... Just acknowledging your comment.  That many drivers of the quality that I'm used to buying would cost about a million dollars... I think he's using the approach that school orchestras do, enough quantity will overcome the quality of each individual...

 

Haha - good point, Con.  :thumb:

 

Andy

 

Share this post


Link to post
Share on other sites

As always these things take far longer than I'd like them to. Anyway the baffles are finally in progress with the most difficult construction aspects attended to.

X0XX5vB.jpg

Still need to add the sloping edges but the main construction from solid pieces of timber stuck together is complete.

 

1C5AyQB.jpg

The back of each driver mount position will be flared out like these woofer holes.

 

Things are looking good and this solid timber was chosen for its very low rate of flaws, veins, and knotholes. Probably still 3 months away before they'll be complete and I can start using them though.

 

On the upside, my friend cabinet maker said it would take far less time to make more in the future if I ever productionised this. I wonder if I could have something ready for next year's hi-fi show...

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...