S.E.X. wiring for planars

[PassionForSound]

I previously haven't bothered with the impedance switch because I only had T1s (very sensitive) and low impedance cans, but now that I have some HE-500s I'm wishing I had the switch.

Until such time as I get around to ordering it (which includes having the spare cash), I'm wondering what other people's experiences are with planars and specifically the HE-500s at different impedance settings.

My S.E.X. + C4S is currently wired on the 4 ohm taps and I am using only 25-30% of the volume range to drive the HE-500s, but I've noticed that the sound from the S.E.X. is better than the Mainline because of the extra power on tap (I assume). This got me thinking, will I achieve any sonic improvement by re-wiring for a higher impedance tap or will I just reduce the usable range of my volume control?

 

[physicsmajor]

The changes are subtle. I have mine set at (checks) 4 Ohms to drive the HE-500s. I tried all the settings, but decided (or convinced myself due to low -> high impedance matching theory; I'm an engineer and there's a potential "this should be right" bias) to stay at 4 Ohms.

The only reason I could see not to stay low was if the power on tap was in any way insufficient. As far as I could tell there was gobs of headroom even with 4 Ohms driving 38. I only use about 20% of the volume pot's range; going above this gets very loud very quickly but still doesn't clip - I've listened with the cans off my head.

YMMV, but that's what my ears say. If you do get the switch and decide to stick with 4 Ohms it would also let you experiment with balanced via the speaker outputs.

 

[mcandmar]

Very interesting to hear as i have just ordered a pair of HE-500's  I found with Grados (just under 40ohms like the 500's), the 4ohm tap sounds the best, at 8ohms the bass sounded a bit wolly. With the HD650's (300ohm) i prefer to run them at 8ohms in balanced mode. With 4ohm they sound a bit too light in the low end, and unbalanced doesn't sound as controlled dynamically to me.

I plan to make up a balanced cable for the HE's so i will report back with my findings there...

 

[PassionForSound]

My thinking is identical to yours, physics, but I'm beginning to discover that planars aren't subject to the same rules as dynamic drivers it seems. Looks like I'll have to do some rewiring and see what I hear...

 

[PassionForSound]

Just re-activating this thread to see if anyone else has tried the S.E.X. with LCD 2s or HE-500s and can comment on the sound with higher output wirings. I am contemplating re-wiring from 4 ohms (current setup) to 8 ohms for balanced or maybe even to 32 ohms.

The manual recommends the 32 ohm configuration for dedicated headphone use, but I'm not sure why given that there seems to be ample power at 4 ohms. Can anyone help?

 

[mcandmar]

You can ignore the 32ohm blurb in the manual, see Doc's post near the end of this thread http://bottlehead.com/smf/index.php/topic,5043.msg50288.html#msg50288

I find i only ever use 4ohm for 32ohm headphones, or the 8ohm for high impedance cans like the 300ohm HD650's.

 

[PassionForSound]

Brilliant - thanks for the link! I think I'd read it before back when I first built the S.E.X. and had completely forgotten what I'd read.

 

[mcandmar]

I received my 500's this evening and have only just started listening.  First impressions are good, i have to admit i was very worried in case i didn't like them and they turned out to be another dust collector like my HD650's.  For detail and clarity they not only match my beloved Ms-Pros, they may even surpass it so no regrets at all with this purchase.

Only thing that is lacking is low end bass.  They are meant to have fantastic low end extension but they cant hold a candle to the Ms-Pros so i suspect the 4ohm setting is too low for them, i will report back when i have tried the 8ohm setting...

 

[physicsmajor]

I received my 500's this evening and have only just started listening...

Only thing that is lacking is low end bass.  They are meant to have fantastic low end extension but they cant hold a candle to the Ms-Pros so i suspect the 4ohm setting is too low for them, i will report back when i have tried the 8ohm setting...

The thing with the HE-500 is that - unlike many other headphones which diffusely boost mid-bass & bass frequencies - they don't. So when transitioning from other headphones, you may feel they are bass lean. I'd encourage you to give them a day or two to win you over.

Where they shine is in bass impact and extension. The HE-500 (at 4 Ohms) hits so much harder than my HD-650s on the same recordings, they aren't in the same league. Put on some well recorded music with a lot of hits, like the Blue Man Group, and your jaw will hit the floor. I really don't think changing the impedance has a big impact on the bass... just so many other headphones boost it, we get used to that.

I'm also a musician. To my ear, the HE-500 conveys reality. Not everyone wants accuracy, but the HE-500's bass is real, extended (pipe organ recordings...), and scary fast.

 

[PassionForSound]

I received my 500's this evening and have only just started listening...

Only thing that is lacking is low end bass.  They are meant to have fantastic low end extension but they cant hold a candle to the Ms-Pros so i suspect the 4ohm setting is too low for them, i will report back when i have tried the 8ohm setting...

The thing with the HE-500 is that - unlike many other headphones which diffusely boost mid-bass & bass frequencies - they don't. So when transitioning from other headphones, you may feel they are bass lean. I'd encourage you to give them a day or two to win you over.

Where they shine is in bass impact and extension. The HE-500 (at 4 Ohms) hits so much harder than my HD-650s on the same recordings, they aren't in the same league. Put on some well recorded music with a lot of hits, like the Blue Man Group, and your jaw will hit the floor. I really don't think changing the impedance has a big impact on the bass... just so many other headphones boost it, we get used to that.

I'm also a musician. To my ear, the HE-500 conveys reality. Not everyone wants accuracy, but the HE-500's bass is real, extended (pipe organ recordings...), and scary fast.

I completely agree about the HE-500s bass qualities. It's not a bassy headphone, but has plenty of impact and extension. I find it actually is quite similar to the T1s, but with a little less mid-bass bloom. The 500's bass is lean (not lacking), accurate and fast, but powerful.

I recently re-wired from 4ohm to 8ohm configuration and believe that it might have brought a tiny bit more bass, but it might be a faulty recollection on my part given the time from first listen through re-wiring to second listen.

 

[mcandmar]

You guys were right, i don’t know if i am adjusting to them, if headphone burn-in is actually a thing, or the pads are sealing better but as the hours go bye i'm finding the mid to low range warmth is really starting to come out and shine. I did switch to the velour pads which i think helped too. Either way i am really starting to fall in love with these.

They are lacking a bit of that euphoric warmth the Grados have in the low to mids, it’s similar to comparing a good tube amp to a solid state, both equally capable but the tube adds just that little bit of magic. High end is more detailed and precise then the Grados but in no way is there ever a suggestion of harshness or sibilance. The real selling point for me is vocals, they sound wonderfully clear, precise and detailed. They are also incredibly fast, it seems impossible to overwhelm them no matter what i tried with them.

Sonically i really cannot find a fault with them, though at half a kilogram they are easily 3-4 times the weight of the Grados which is taking some getting used to. I also need to look into headband mods as my head is slightly too small for them, yeah yeah stop laughing!  Overall the pros far outweigh the cons, these might just be my new favorite headphone, and they pair up wonderfully with the S.E.X. amp.

Have any of you replaced the cable?  The stock one makes an annoying microphonic sound when you rub the cable which i don’t like, and i have an XLR plug here to make a balanced cable, just don’t have the nerve to 
snip the end off the supplied cable.  Basically i'm looking at the extra headphone connectors in the box and an XLR connector wondering how best to join them. I have never made a headphone cable from scratch before but i did find this on eBay http://www.ebay.co.uk/itm/5meters-1-0mm-high-purity-silver-plated-OCC-teflon-wire-for-audio-DIY-0-26x19-/320998604353?pt=US_Audio_Cables_Adapters&hash=item4abd01fe41 which with a little bit of weaving should end up looking like the stock cable.  Any thoughts?

I still haven’t tried the 8ohms setting, waiting until i am 100% familiar with them before experimenting. They do require almost twice the volume of the Grados for the same output level which is roughly the same as the HD650's, but still only ~50% volume so there is certainly no lack of power to drive them.

 

[physicsmajor]

This link (the rest of the page is a trove of great balanced cable DIY info as well) is exactly what you're looking for. Converting the stock cable is as simple as cutting off the stock adapter and resoldering. The stock cable is already balanced to the jack, then both grounds are soldered together. Otherwise, some Canare Star Quad is probably what you want.

http://robrobinette.com/BalancedCable.htm#Convert_HE-500

I haven't gone this route yet myself, but probably will in the near future. Some people also think replacing the pads is an upgrade. I replaced the HE-500 stock pads with a spare set of velours from my Fischer FA-003, but not because of sound. My ears stick out a bit, and with the stock pads they were brushing the inner gauze... They are now firmer and enforce a bit more separation between my head and the 'phones.

 

[mcandmar]

Canare 4 core looks like an interesting option, seems readily available and sensible money too, thanks!

I noticed the stock cable had the four cores but could'nt bring myself to chop it up.  For example here is what i did for my HD650's, cheap aftermarket cable i bought second hand for £30, snip, splice on XLR = one cheap skate balanced cable

 

[mcandmar]

And were done, i have some paracord on order to pretty it up but for now its fully functional. I'll do some testing over the weekend to compare balanced vs unbalanced and see what changes i notice if any.

 

[mcandmar]

....after a week using the new cable i finally flicked the switch into balanced mode and there is a noticeable difference, more of a difference than i remember when i converted the HD650's. Similar to the HD's i 'm finding the low end bass more controlled, and i would even go as far as to say there is more/better sub bass then before.  Certainly i am more aware of deep bass frequencys than before, or maybe that's just a result of being better defined.  I could also convince myself they sound clearer and less muddy overall, either way it seems it was a worthwhile en-devour to convert them.

 

[PassionForSound]

I think I'm swaying towards going and buying a 4-pin XLR socket so I can use my balanced cables with the S.E.X. as well as the Mainline. You might have just pushed me over the edge, Mark!

 

[mcandmar]

That evil voice in your head again, go on, you know you want to

You could do what i did and add both TRS and XLR sockets to the chassis, an easier option would be to make up an XLR to speaker binding posts cable using one of these http://www.neutrik.com/en/xlr/xx-series/nc4fxx-b

Personally i would just drill a hole in the chassis plate but i appreciate how awkward that would be on an assembled unit.

 

[PassionForSound]

Yeah. I'm actually looking into something a little mental...

I'm going to use the reaming attachment for my Dremel to cut out the XLR hole in the place of the existing TRS and am then hoping to replace the binding posts with additional RCAs so that I can have signal into SEX, but then take signal out of SEX to run to the Quickie so I'm not always switching RCA cables. The trick now is to see if I can find an RCA socket that will fill and fit the hole made for the binding posts.

 

[PassionForSound]

I finally managed to take the time to cut out the hole for an XLR socket in my S.E.X. and wired it balanced as per the great instructions here: http://bottlehead.com/smf/index.php/topic,3362.0.html

I'm currently listening to my LCD-2s with the new configuration and it's taken them to a whole new level of performance - more so than the T1s with the Mainline in balanced mode (i.e. larger leap, not necessarily better overall, just different)

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