juke
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Post by juke on Feb 7, 2015 16:36:56 GMT
Syd, I'm sorry. I know I do this, but I can't help being enthusiastic over gear that is superb. I covered the cracked paint on mine by putting a Beyer strap on the headband. That way, you don't see it and it's more comfortable. I think I'll be looking for a Kameleon myself now. I don't really know whether the mains driven one is much different to the portable one. The only reason I have a mains one is because I mentioned it to Frans who made this one for himself at home. Much what I was after; rather than a portable battery powered unit. It has given me much greater respect for the Senn HD650 tbh. It goes into another league. The sound is much the same, but more lower bass welly and less mid bass hump. It transforms it into a different headphone in one respect, whole still retaining some of the Senn warmth. Open as heck as a result. Powerful and full bodied and basically very natural sounding. It is kind of similar to the HD600 with a better treble. Not so grainy if you like. More refined. I think I'd be using it solely for the hd650. I've tried the DT990 filter today. It's a little more strident in the top than the Senn and the bass hump is down but the Senn is spot on for me. I put the Senn filter straight back!! I like the Ember and Polaris a lot with the Senns but the Kameleon makes it take off. The old colourations recede and it sounds like a lovely toned high end headphone. No problem Ian, I regretted selling my Senns, but the paint issue annoyed me. I like your idea of the Beyer strap, so I'll get one - as I weakened last night and grabbed one of Amazon's remaining bargain priced pairs  I have plenty of space since I sold off 4 or 5 'phones a while back on Ebay, no regrets about any of those and I think the 701s will go next. I just really like the build quality of them but that's a pretty stupid reason for holding on to something! I'll just check my components stock later to get a Kameleon filter built, ready for the Senn's arrival. The Kameleon is an excelent little amp, I would rather it had a volume control but still so handy. I copied Fran's sliding case top idea which makes a world of difference for such a minor mod. Syd |
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juke
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Post by juke on Feb 7, 2015 16:47:30 GMT
Yes, I remembered you had an entry about your mains version back near the start of the thread, just thought maybe the mains power supply might give it more oomph.
The Kameleon does a really good job with the HE-6 but I do find I use it a lot at close to full volume, and would rather there was slightly more power in reserve. It still does much better than many of my
mains-powered HAs.
It has more volume than I would ever need with all my other 'phones including the T50, highly recommended.
Syd
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solderdude
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Post by solderdude on Feb 7, 2015 19:49:45 GMT
The filter for the HE-6 was designed for the HE500 (which basically needs the same correction)
The HE500 has a much higher sensitivity.
I could have a look to increase the gain of the filter so you get better travel on the pot.
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juke
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Post by juke on Feb 7, 2015 23:02:08 GMT
The filter for the HE-6 was designed for the HE500 (which basically needs the same correction) The HE500 has a much higher sensitivity. I could have a look to increase the gain of the filter so you get better travel on the pot. That would make a great difference Frans. Being so close to 'flat out' really shows up the variance of output level of a lot of my tracks. Syd |
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Rabbit
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Post by Rabbit on Feb 8, 2015 12:44:51 GMT
I had a nice long listen with the Beyer dt990 filter today.
Slightly different to the Senn sound but actually quite close, which is really odd when you know these two headphones.
Without filter, the Senn can be quite bloaty in the mid bass and 'seem' recessed whereas the Beyer hits hard in the bass but has a treble edge as well. So I tend to go between the two of them depending on what I'm listening to.
The Senn filter makes it jump to life with a more apparent top end and less bloating. Very low sub bass is more apparent and for me, this becomes an amazing headphone.
The Beyer goes the other way!! The treble is less piercing. Sub bass is there and the mids are more apparent in comparison to it without the filter. The bass response is slightly different in that it hits hard, in a very similar way to the Senn, but I think that it just lingers for slightly longer so is slightly 'thicker' sounding in the bass than the Senn.
So the Senn actually sounds a fraction more open, although they are both pretty similar now. It's quite weird to have a Beyer and a Senn kind of sounding similar.
Both are improved. Beyer actually, quite a lot but my preference is still the Sennheiser as a headphone. It seems slightly more natural and open. However, the Beyer is really tastey on rock music.
I'd say that the Senn spits out bass transients and the Beyer thuds them out. That seems to be the most obvious difference between the two headphones, but overall, the sound of both is uncannily similar!!!!
If you like the Beyer sound, it's once again, still there but my goodness is it improved.
So now, I need two Kameleons!!!!!! No not really. Some self restraint is needed here.
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solderdude
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Post by solderdude on Feb 8, 2015 13:57:00 GMT
I have 3 kameleons (well 2 at the moment) for that reason alone.
One for HD650, one for T50RP on the go and one 'stationary'.
For my stationary T50RP I have an amp with a filter built into it (so it can only work with the T50RP alas as there is no switch currently) and also a dedicated filtered portable amp for the DT1350 (that thus can only driver DT1350's)
My regular amps are used for testing/measuring and on the PC soundcard.
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Rabbit
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Post by Rabbit on Feb 8, 2015 14:04:49 GMT
That's what I'd do Frans. Fix the filter in for Senn hd650. I've become obsessed!!!
I can see continual movement of the filters causing the pins to wear or the socket. (Like valves) I'd lock a Senn filter in there. No lid then as well.
It's just fabulous sounding and I can't stop myself revisiting loads of recordings which I'm hearing in a new light. Even hearing myself is enlightening !!!!!!! Proper bass at last.
I tell you, Senn could make a killing .... Amp and headphone as a matching combo.
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juke
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Post by juke on Feb 18, 2015 14:47:58 GMT
My new Senn 650s arrived last week. I had a Kameleon filter ready for them.
I tried the Senns with the 'standard' general purpose filter first just to remind myself of their sound. As I am so used to the filtered HE6 and TP50s I found the new 650s really boring, sort of warm and lacking detail.
Quickly switched filters and could hardly believe my ears!
Totally transformed, evrything exactly as Frans and Ian have said, I just hadn't grasped what a tremendous difference Frans has achieved, brilliant.
These will see a lot of use. I decided to build a 'permanently coupled' Kameleon just for these, as I had bought a board, case and most of the parts some time ago.
The current amp was built by Javier and is superb.
Sadly, my second amp is now built but has a fault or two.
I'll set out the problems in a separate post.
Syd
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juke
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Post by juke on Feb 18, 2015 14:53:43 GMT
I thought the build of my second Kameleon had gone well, but the volume is very low, maybe 10% of what is possible with the Javier-built amp.
Also the on-off switch makes no difference, plays away regardless of position (tried two different switches, both tested and work well otherwise. Also the battery charging light comes on if the USB charger is inserted
and the music plays on.
I hope you have some ideas Frans, I can find nothing wrong. I haven't yet built it into it's case so the two front LEDs haven't been soldered into the board yet, in case it matters.
Syd
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Rabbit
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Post by Rabbit on Feb 18, 2015 15:56:14 GMT
My new Senn 650s arrived last week. I had a Kameleon filter ready for them. I tried the Senns with the 'standard' general purpose filter first just to remind myself of their sound. As I am so used to the filtered HE6 and TP50s I found the new 650s really boring, sort of warm and lacking detail. Quickly switched filters and could hardly believe my ears! Totally transformed, evrything exactly as Frans and Ian have said, I just hadn't grasped what a tremendous difference Frans has achieved, It is absolutely outstanding. Mine has gone back now sadly, but the sound from the HD650 is extremely good. They light up. |
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solderdude
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Post by solderdude on Feb 18, 2015 16:09:51 GMT
Something seems to be wrong with the MOSFET or the opamp circuit driving it.
Could be caused by the extremely small zener diode that may be the wrong way around.
If the jumper is set to switch off the amp while charging than most likely the MOSFET is conducting constantly.
Before looking at the volume perhaps test the voltages in the power supply circuit.
With the black test lead on the -V terminal (con8) and the meter set to DCV.
Can you post voltages you measure (red lead on):
D3 (both leads)
Z1 (both pins)
R16 (both leads)
audio ground
Cathode of D8
Jumper J1 (both pins WITHOUT the jumper)
repeat the measurements with 1 battery connected and the other one removed but the battery connector clip connections need to be shorted.
DON't short the battery !!!!
The 2 batteries are in series....
The measurements below must be done with the black lead connected to the audio ground (running on 2 batteries) no filter module inserted:
Pin 7 of one of the OPA's (doesn't matter which)
Pin 6 of one of the OPA's both opamps.
Pin 4 of on eof the OPA's (doesn't matter which)
Anode D7
Anode D8
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juke
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Post by juke on Feb 18, 2015 17:18:02 GMT
D3 (both leads)6.54v neg side 19.53v + side: one batt 3.67, 9.73
Z1 (both pins) - side 5.6 other side 0: one batt 0 and 0
R16 (both leads)0v both sides: one batt 9.72 9.63
audio ground
Cathode of D8 0: one batt 0
Jumper J1 (both pins WITHOUT the jumper)2.94 7.81 one batt 2.19 5.65
Pin 7 of one of the OPA's (doesn't matter which) -.42
Pin 6 of one of the OPA's both opamps. -.06 both
Pin 4 of on eof the OPA's (doesn't matter which) -.042 both
Anode D7 -.04
Anode D8 -.04
I didn't have the filter module in for thr the first tests, is that OK
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Javier
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Post by Javier on Feb 18, 2015 17:34:06 GMT
IIRC Frans said it didn't work without the filter board in place.
Sent from my GT-I9100 using proboards
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juke
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Post by juke on Feb 18, 2015 18:49:01 GMT
Thanks Javier! This are the new readings with filter in for first part..
If the jumper is set to switch off the amp while charging than most likely the MOSFET is conducting constantly. It is.
Before looking at the volume perhaps test the voltages in the power supply circuit.
With the black test lead on the -V terminal (con8) and the meter set to DCV.
Can you post voltages you measure (red lead on):
D3 (both leads)6.51v neg side 9.34v + side: one batt 3.66 9.68
Z1 (both pins) side 0 other side 5.59: one batt 5.31 and 0
R16 (both leads)0 and 0 both sides: one batt 9.68 9.57
audio ground 0.41 one batt 0.41
Cathode of D8 0: one batt 0
Jumper J1 (both pins WITHOUT the jumper)2.92 7.77 one batt 2.18 5.62
repeat the measurements with 1 battery connected and the other one removed but the battery connector clip connections need to be shorted.
DON't short the battery !!!!
The 2 batteries are in series....
The measurements below must be done with the black lead connected to the audio ground (running on 2 batteries) no filter module inserted:
Pin 7 of one of the OPA's (doesn't matter which) -.40
Pin 6 of one of the OPA's both opamps. -.06 both
Pin 4 of on eof the OPA's (doesn't matter which) -.042 both
Anode D7 -.2
Anode D8 -.33
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juke
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Post by juke on Feb 18, 2015 18:52:48 GMT
For just a 'normal' amp without filter, I think that you need to have a 'straight through' filter installed, if you see what I mean. Saw your post too late Ian. I used the 'New Senn 650' filter. I'll leave it for now before my eyes fall out of their sockets! I'll check later if Frans comes on and redo them if it's needed. Syd |
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