juke
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Post by juke on Apr 13, 2013 12:26:00 GMT
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Certainly does, I'll be wanting a few please!
Syd
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solderdude
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Post by solderdude on Apr 13, 2013 15:17:37 GMT
Ember is in and tested but I am not satisfied and we are going to redesign some of it..... The filter PCB has had some minor layout changes and after I do another thorough check will send it to the manufacturer. For info on this new PCB see the website: diyaudioheaven.wordpress.com/schematics/headphone/Info will always be at this location.
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Post by imagemaker18 on Apr 14, 2013 14:56:06 GMT
BMF, Frans designed the Sunrise/Horizon amps with Jeremy in the USA so those tubes might well come in handy!! I have a Horizon which is really powerful and dynamic. (amongst my collection!!) There is something about valves that I really enjoy as well. New amp on the way as well - the Ember. Ian, I also have both the Sunrise and the Horizon and was using the Horizon extensively until I bought and modded the T40 and T50, which require more power. I then switched back to the Sunrise, which at 50 Ohms produces much more power than the Horizon. Check out Frans' specs on both these amps that he tested some time ago. Frans, please correct me if I am wrong. Keith, I agree with you about the Telefunken tubes! I have several of them, and to my ears none of the other tubes can touch them in clarity, transparency, and lack of audible distortion! I use Telefunken ECC88 tubes on both my Sunrise and the Horizon. Cheers!
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Rabbit
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Post by Rabbit on Apr 14, 2013 17:14:46 GMT
oh .... don't tell me that Israel. My Sunrise has gone into the Sunset and rises every day in another house!
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solderdude
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Post by solderdude on Apr 14, 2013 18:36:21 GMT
The upcoming Ember will be best of both worlds. high power for low and high impedance headphones....
The SR has twice the power (thus can play 3dB louder) than the Horizon. The Ember will the twice the power of the SR (low impedances) and has the same power for high impedance headphones as the Horizon. Also it doesn't get hot (not class-A) and biasses itself and auto selects the heater arrangement.
When I am done playing with the proto I can send it to you Ian so you can have a listen.
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Rabbit
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Post by Rabbit on Apr 14, 2013 18:55:48 GMT
Actually, when you said further changes were going to be made, you did get me curious, Frans. Was it the listening to the amp that made you want to make changes or second thoughts? Would you notice if a Bravo came back?
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solderdude
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Post by solderdude on Apr 14, 2013 19:16:14 GMT
The changes needed are of electrical/thermal origin and have been corrected/altered in the prototype but requires a redesign for the final version. It has to do with thermal problems of the output opamp used when it pumps out close to 2W power. The opamp get's quite hot as it doesn't have heatsinking. Need to play with it and alter things a bit more though and measure it as well.
For normal to loud listening levels this is no problem, but it is on a test bench with continuous sinewaves in 32 Ohm loads it is.
a Bravo I'd notice .... an Horizon might not be detected.
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Rabbit
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Post by Rabbit on Apr 14, 2013 19:26:45 GMT
Great. As you know, I'm not too happy when gear gets a bit too warm. It's fine at the start but over time, it can cause problems which isn't good news for people on budgets.
All of my Bravo types have now fully cooked themselves to death!!
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Deleted
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Post by Deleted on Apr 15, 2013 12:05:14 GMT
Quick question for Frans (or anyone else that knows the answer) I've got myself a T40 and checking the T40 pdf it shows "malleable eraser" to mass-load/deaden the driver baffle. Do you mean Blu-tack?? And if not - will Blu-tack do the same job? Jeff en.wikipedia.org/wiki/Blu-Tack
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BMF
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Post by BMF on Apr 15, 2013 12:11:07 GMT
Scroll down to 'visco elastics.' I don't know about the accuracy of these data. qualia.webs.com/newdampingfactors.htmI've tried basic non-drying plasticine, blutak, re-usuable erasers, Newplast (readily available and cheap in The U.K.), and my own formulation of tungsten putty. I seem to get the best results from Newplast and tungsten putty. Newplast is much easier to use and can be easily removed with a a small screw driver or similar tool. I've found that Dynamat X-treme installed surrounding the ear side of the drivers has a similar effect as Newplast in the baffle compartments. You have to sand or chisel off (I use a Dremel rotary tool or X-acto knife with chisel blade) the dust cover surrounding the ear side of the driver before installing the Dynamat. Overlay the Dynamat with Paxmate Plus or Silverstone acoustic foam. This combo cuts down on both mecanically-induced resonance/distortion and ear side reflections, as well as creates a smaller chamber for "funneling" the sound from the drivers to your ears. I've also begun to try Paxmate Plus on the "front" half of the pads' inner "walls" to reduce reflections off the pads....jury is still out on this one. Anyone tried any of these mods? Or, have other suggestions? Word of caution: Don't use "bake to dry" plasticine/clay. It reacts with and literally melts the plastic baffles and cups. This was discovered by 'mrscotchguy' on head-fi. several months ago. Luckily, he knew someone with extra cups and baffles and successfully transplanted his Fostex T20RP mk2 drivers. Off topic: After several modding opening/closing of the cups, the cup threads tend to weaken and eventually will fail. This prevents a tight seal and results in massive bass loss. If anyone strips the plastic threads in the cups or "outside" metal rail hanger holders, check my Incremental Mods and Measurements for a solution ---> Post #1: www.head-fi.org/t/618659/fostex-t50rp-incremental-mods-and-measurements
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Rabbit
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Post by Rabbit on Apr 15, 2013 14:14:08 GMT
Jeff, I'm not keen on plasticine because over time, I suspect that it will dry up and shrink, like putty. Then it could plop out on a knock. Frans used the eraser stuff because it's really tacky. I seem to remember that he felt the effects were actually minimal though. It served to 'stiffen' the baffle which is a good thing but he wasn't sure that its effects were that great. The wool and driver covers were more influential. Jeff, I know you're going to dampen one but Frans found the drivers weren't very well matched. He determined the amount of stuffing by watching the actual measurements of each cup. If it is done a little bit 'roughly', it may not be that well matched between the cups; therefore imaging may be a little off. I noticed the wool offer - really surprised since you appear on here and didn't get yourself banned!!! ;D
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solderdude
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Post by solderdude on Apr 15, 2013 15:51:21 GMT
Quick question for Frans (or anyone else that knows the answer) I've got myself a T40 and checking the T40 pdf it shows "malleable eraser" to mass-load/deaden the driver baffle. Do you mean Blu-tack?? And if not - will Blu-tack do the same job? Jeff en.wikipedia.org/wiki/Blu-TackThe T40 and T50 are similar once modified. I differentiate the 2 articles for different pads used. If you plan to use the SRH940 pads you can use the T50RP article. BMF had kindly sent me some Newplast and could compare it with maleable eraser (the stuff kids like, sold in the bookstore). The mass is about the same and the newplast is somewhat easier to apply 'neatly'. It can be pried off easier too which makes me think the maleable eraser is stickier and know it doesn't dry out. Had plenty of it so used it. I used the Newplast in Juke's T50 and took measurements before and after application of the newplast. I could not find any 'notable' changes in FR nor in CSD, but my CSD may not be resolving enough, need to try ARTA. With notable I mean differences bigger than those I get when remeasuring the same headphone a few times in a row while slightly repositioning them. It should be noted that BMF has done LOTS more experimenting than I have. Juke's T50 drivers (black ones) also weren't matched very well either b.t.w. but with appropriate dampening and playing with the bass port I got the closely the same. see: diyah.boards.net/index.cgi?board=technical&action=display&thread=61
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juke
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Post by juke on Apr 15, 2013 17:41:27 GMT
Didn't mean to cause you so much bother Frans, but it's great that you have matched them so closely!
Syd
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BMF
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Post by BMF on Apr 15, 2013 17:50:50 GMT
I'm not convinced that adding anything to the baffles makes an appreciable difference in sound quality. I've been moving away from using it for a couple of months. The damping scheme and pads used account for 90% of modification improvements with about equal variance, IME. Take a great sounding mod configuration and put on a pad different than used during tuning and the sound will likely be quite different.
I think the simplest mod I've made that sounds really good is 1x7x7 cm "slab" of Grodan rock wool compressed into the cups and Shure 840 pads. Nothing else unless I want the extra 10%; and who doesn't! LOL
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Rabbit
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Post by Rabbit on Apr 15, 2013 18:11:32 GMT
BMF, you're like a breath of fresh air!! Enthusiasm. That's what I really enjoy reading and at this moment, I'm listening to my T40's. Frans at one time said when I was particularly stressed, 'Listen to some music on the T40' - how right he was. It's relaxing and just exhilarating and totally takes me away from thinking about anything else. I still listen now for real relaxation and it never ceases to surprise me what it can reveal in the music I'm listening to. They are just nothing short of stunning. It never ceases to amaze me how deep they can go on some recordings and yet on others, they don't - depending on the recording. They have this deep, powerful sound which is on the 'dry' side if you compare them to the HD650, but the sheer power and depth they deliver is absolutely brilliant. The HD650 seem to be more full of resonances that the T40 doesn't produce. I'm not exactly sure why that is, but the HD650's sound like they are in another room on the same recording. I can't help using them at life volume. They are so enjoyable. In fact, I'm quite happy with them as a straight headphone. Fran's filter brings up the top end, but to me, it really just doesn't change the character of the headphone, but just extends it. I like it so much, I've been looking for a portable that produces enough current to drive it properly. At the moment, I'm trying out the O2 on 6X gain and it's just brilliant to think that you can now get this kind of quality from a portable set up. Syd, Frans got mine absolutely right!! They are really lovely and he teased me with them before he sent them by wearing them and telling me while we were chatting online!!! They seem to make many headphones seem gutless with no real body or even synthetic sounding. I've moved from the DT150 to the T40 for work stuff. It's just streets ahead. Your first feeling is that nothing seems to stand out and on extended listening, you start to discover just how natural sounding they actually are. I would say use a powerful amp though. They soak it up and start to really sing on the end of real power.
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