Crispy
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Madrigal music is playing - Voices can faintly be heard, "Please leave this patient undisturbed."
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Post by Crispy on Jul 21, 2013 19:38:33 GMT
I think you will like what is coming with an alloy / metal chassis. May not be the last say in noise rejection as we will not be hiding a tube and the guts totally in a metal can (that can be left for the diy crowd), but it will keep with the current style of the amplifier. I aim to keep it that way for reasons you stated - it is about the sound, art, build quality and attention to detail as a whole package. Anyone can stick a machine built mass produced PCB into a can, but we pride ourselves in workmanship, quality and our signature look / layouts. I will look forward to seeing the metal enclosure, but the glass one interests me more, you just cannot hide away all that beautiful workmanship. Agreed on the glass! I have been looking at water-jetting glass as a possible chassis option as it would be rather unique for us in our style. Edge finishes are not always the greatest though with jetting and I worry about safety and shipping (mainly safety as we overpackage our built amplifiers) I think I could fall in love with a 3/16th thick starphire glass upper and lower chassis with machined edges for a perfect finish. Starphire is a low iron, beautiful glass with a blue tint (blue when looking through the width)I have used it often with aquarium work. I had a quote out a few months ago for machined glass but good grief they wanted a mint for lower volume. Still keeping a lookout though. A couple new places have come up locally so will see what they say. Keep looking for the glass alternative Jeremy, I think I could also fall in love with 3/16th thick starphire glass with a blue tint to match the cool blue led when set to that colour. |
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Crispy
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Madrigal music is playing - Voices can faintly be heard, "Please leave this patient undisturbed."
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Post by Crispy on Jul 21, 2013 19:58:23 GMT
That's a thorough review and think Jeremy is likely to appreciate. Thanks Frans, I do find reviews difficult to write me being a total novice at anything like this, but I know when something sounds good to my ears and the Ember certainly sounds superb. You mentioned 'gain' but the jumpers you refer to are output resistance settings. The higher the value the softer the headphone will sound when the volume control isn't moved. The effect is greater for low impedance headphones than for high impedance headphones. The low impedance setting is most likely to sound best on the DT770. The bass might become bloating and or more boomy on higher output resistance settings. The output Resistance setting is not of any influence in pre-amp mode as they are only in the headphone socket's pathway. Aha, resistance settings? they still confused me because the low setting should have given me the least resistance and should have sounded the loudest, yet the medium setting sounded the loudest to me? STRANGE! I did know the settings were for headphones only, but it was worth pointing out to other members who are in line for a listen. Encased in solid acrylic it might be difficult to change jumpers, tubes, tweak components or (heaven forbid) do repairs  Also the heatsinks (responsible for the low running temps) wouldn't work any more. Thanks for the nice write-up ! Sorry I mis-led you on the solid acrylic enclosure Frans, it was only meant to give you an idea of what the Ember could look like if it was enclosed in some sort of solid or semi open glass case, where everything would still be on show  |
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juke
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Post by juke on Jul 23, 2013 22:08:03 GMT
the burning question for me is will this amp drive the he-6 to a decent level? . Yes it does !!!. Mick. I'm looking forward to your review Mick. Any thoughts so far compared to your Hifiman HE-5 amp? Syd |
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Post by jhelms on Jul 23, 2013 22:13:49 GMT
That is the protection circuit - it is active if the led is red and always turns on when you first power up the amplifier. After about 30 seconds of being powered on, it will turn off with a click. This can also activate if the amplifier ever overheats. To note, even with 15ohm dummy loads driven into a pure square wave, we could never get her close to overheating. User manual Project Ember Manual |
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Post by jhelms on Jul 24, 2013 15:20:31 GMT
Hey Mick, That is such good news to hear multiple customers say Ember powers the HE-6's effortlessly. And appreciate the comments on the aesthetics! Guess open designs can be one of those love/hate deals depending on the person. Definitely keep us posted on further listening spells and roll some tubes - have fun with it!
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dicky
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Post by dicky on Aug 1, 2013 20:46:03 GMT
Mick did you compare with your panda?, assuming you still have your panda of course Simon Simon, my Ember arrived today and I've fired it up to check it survived being kicked around in Customs for a week. Anyhoo, what I have noticed is how much quieter it is - I have 2 Pandas (one standard gain and one +6dB) and both are quite noisy at high volume levels. Otherwise I haven't really listened to it yet - too much else going on at the moment.  Oh, I should add that the build quality is very good! Mine came with a Russian valve - a 6N1P-VI. Dicky |
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Post by afrenchguy on Aug 3, 2013 21:06:32 GMT
:) power is not a problem  |
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solderdude
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Post by solderdude on Aug 3, 2013 21:42:36 GMT
Does it drive the K1000 to more than reasonable levels ? It should be able to reach 106dB which is quite loud with 1.8W into 120 Ohm. The K1000 puts out 74dB/mW That is hard to test for us as there aren't many of those K1000's around.... I know it does drive the HE-6 quite well too, but the HE6 is a tad more efficient with 77dB/mW. The HE-6 should reach about 108dB SPL (around 1.5W) which is effectively equally loud. Both are quite inefficient headphones but have a very nice sound. |
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Post by itsalive on Aug 4, 2013 13:05:03 GMT
Does it drive the K1000 to more than reasonable levels ? It should be able to reach 106dB which is quite loud with 1.8W into 120 Ohm. The K1000 puts out 74dB/mW That is hard to test for us as there aren't many of those K1000's around.... I know it does drive the HE-6 quite well too, but the HE6 is a tad more efficient with 77dB/mW. The HE-6 should reach about 108dB SPL (around 1.5W) which is effectively equally loud. Both are quite inefficient headphones but have a very nice sound. My friend who own the Ember and the K1000 said that he won't go further 40% of the volpot, it's loud enough for his taste ! |
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Post by itsalive on Aug 6, 2013 11:36:12 GMT
 Ember received  |
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Post by itsalive on Aug 7, 2013 15:33:14 GMT
 The Project Ember with 6GU7 PhilipsECG and a brand new DAC : "Philips Is 5021" (built in 1995 !), great combo, and project Ember is very Quiet, no background noise with my K601, very weighty sound ang great bass on a K601, very pleasant sound ! |
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solderdude
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Post by solderdude on Aug 7, 2013 18:24:57 GMT
The K601 may sound 'best' when the output R is set to 'high' (120 Ohm).
Be sure to try all options though.
Maybe 0 or 35 Ohm suits your taste better.
6GU7 has very long plates and the heater current is a bit on the high side (600mA).
The heater regulator in the Ember (and Horizon) are spec'd for 500mA continuous but tests have shown it can handle 600mA heaters without failing.
In reality the heater current will be somewhere between 500mA and 600mA anyway.
Starlight and Sunrise(II) heater regulators are spec'd for 1A continuous.
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Post by itsalive on Aug 7, 2013 19:23:30 GMT
The K601 may sound 'best' when the output R is set to 'high' (120 Ohm). Be sure to try all options though. Maybe 0 or 35 Ohm suits your taste better. 6GU7 has very long plates and the heater current is a bit on the high side (600mA). The heater regulator in the Ember (and Horizon) are spec'd for 500mA continuous but tests have shown it can handle 600mA heaters without failing. In reality the heater current will be somewhere between 500mA and 600mA anyway. Starlight and Sunrise(II) heater regulators are spec'd for 1A continuous. I know about the heater current I will also test 12BH7a, 6N1P-Vi, 6N2P, ECC81, ECC82, ECC83 can i put a little radiator on the DC-DC Regulator? can i put a dc-dc regulator which can handle 1A continuous on the Ember? |
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solderdude
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Post by solderdude on Aug 7, 2013 19:50:25 GMT
ECC83 might be a bit hissy... depending on the quality of the tube.
You could mount some heatsinks on the DC regulator but don't think it will do that much as the thermal resistance of the 'casing' is a bit on the high side.
a small heatsink glued on with some thermal glue might lower the temp a bit.
I discussed the 1A option with Jeremy a few times.
It always means you will have to use 2 regulators or need to use DCDC converters with a bigger footprint.
The switch mode regs that can handle 48V input voltage are spec'd at 0.5A and the ones that can handle up to 30V can handle 1A (it's a power issue so higher voltage means lower current for the same power.
According to the manufacturer the 0.5A specs are deliberately held on the 'low' side and have a good margin upwards so can handle more than specified.
Jeremy tested a regulator on 600mA and has amps running continuously with 600mA tubes (AFAIK) and gave no problems.
To create a 1A capable PS the options are different and more expensive and bigger components,
Using 2 in 'parallel' or using a 0.5A version to go from 48V to 24V and feeding that 24V to a 1A reg.
This is possible because the reg is of the switching kind and not linear.
As far as we know now the 600mA tube is not a very big problem though on the 0.5A regs.
6N1P is liked by many.
Both 12BH7a and 6N1P-Vi are 600mA tubes, the others between 300 and 350mA
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Post by jhelms on Aug 7, 2013 20:34:04 GMT
Per Frans post ^ I have only had a couple of odd 12bh7's which were power hungry enough at startup to make the led under the tube flicker for a second. Otherwise no worries with the 6n1p, 12bh7, 6gu7's and so forth. I run them often and have torture tested the reg we use quite often. Very pleased with the quality of the reg.
There are a few tubes which cannot be run in Ember / Horizon as they are VERY power hungry. Such as the 6n6p or 6n30p. We are talking between 800 and 900mA! With these, even the tube gets so hot you cannot touch it around the middle once warmed up. Sunrise and Starlight will run these to note.
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