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Post by luckbad on Feb 20, 2016 21:45:21 GMT
I have owned the Project Ember II, Project Polaris, and Project Sunrise III (in that order).
I currently have the Project Sunrise III at work and swap between Voskhod 6N6P/6H6pi and Electro-Harmonix 12BH7 Gold Pin tubes.
The Project Ember II is at home and currently has an RCA 12AU7 clear top in it, but I have an Electro-Harmonix 6H30Pi Gold Pin on the way from Jeremy today (more cost than some places, but I support Jeremy's business).
Right now, I'm finding that I long for the romantic sound of the Sunrise III. The Ember II is certainly more dynamic and versatile, but it seems to be missing out a little on the lush, musical euphony of the Sunrise III somehow.
Is that tube choice, or amp choice?
Now getting to the actual subject, the Project Horizon.
Is the Project Horizon III of the same musical lineage as the Sunrise III?
It is listed as being for higher impedance headphones, and I'm wondering if I would be okay using these two headphones:
Sennheiser HD650: I assume this would be great with the Horizon, and would be used 4-5 nights a week with it.
JVC HA-DX2000: Impedance - 64 ohms
& Sensitivity - 102 dB/1 mW. Would this do well with the Horizon? It would be used 2-3 nights a week with it (and is otherwise used at work with the Sunrise III).
Thanks! Perhaps my ears or placebo are causing my to miss the Sunrise III while listening to the Ember II or the tube is not to my taste / isn't fully broken in.
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solderdude
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Post by solderdude on Feb 21, 2016 9:35:46 GMT
The project Horizon is sort-off inbetween SR and Ember.
The tubes run on the same (higher) voltage in Horizon and Ember.
The output stage in the Horizon is most similar (but not exactly the same) as the SR
The Horizon is better suited for HD650 but can be used without any problem on the JVC as it is a high sensitivity headphone it can still play very loud.
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Post by luckbad on Feb 22, 2016 2:01:27 GMT
Thank you sir! I placed an order with Jeremy for the Horizon.
I'll be doing a review of all three at once on Basshead.Club.
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Post by luckbad on Feb 26, 2016 7:29:46 GMT
solderdudeJust got in the supercharged Horizon III today. One issue I'm having is that I intermittently get a scratchy/static type sound that shows up for a couple of seconds then goes away maybe once every minute or two. It's most obvious when no music is playing, but I hear while music is playing as well. This is not happening with the same tubes from Ember II or Sunrise III. I'm using HD650s. Any ideas what it could be?
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solderdude
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Post by solderdude on Feb 27, 2016 12:22:20 GMT
Strange, I would suspect the heatersupply is doing something weird ?
Have you asked Jeremy yet ?
It should be the exact same board as the SR-III.
The main differences are the operational points of the converter and the output stage as well as supply voltage.
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howie
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Post by howie on Feb 27, 2016 13:20:57 GMT
solderdude Just got in the supercharged Horizon III today. One issue I'm having is that I intermittently get a scratchy/static type sound that shows up for a couple of seconds then goes away maybe once every minute or two. It's most obvious when no music is playing, but I hear while music is playing as well. This is not happening with the same tubes from Ember II or Sunrise III. I'm using HD650s. Any ideas what it could be? I think I know the sound you are referring to. I can usually get rid of it by a slight tweak of the bias screw. It's tube dependent though. Horizon can be a little more fussy with tubes than Ember and can be a bit noisy with the more exotic ones we have been trying with Ember. If I stick to noval 9 pins there's not a problem. Most dual triode octals are fine too but a few do make that intermittent shuffly/ scratchy noise. Of course some of these tubes are old and of doubtful provenance anyway. I have the Starlight as well and it's quite possible for the same tube to produce noise in one amp and not the other. Incidently, my favourite Horizon tube type is the E80CC. Tungsram's is clean and detailed and Valvo (Hamburg) is similar, just a little warmer. Both quiet as mice! Will look forward to your comparisons. Maybe I should get a Sunrise too. |
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Post by luckbad on Feb 27, 2016 15:45:12 GMT
Strange, I would suspect the heatersupply is doing something weird ? Have you asked Jeremy yet ? It should be the exact same board as the SR-III. The main differences are the operational points of the converter and the output stage as well as supply voltage. Yep. Waiting on a reply. It seems to have something to do with power. If I plug it in anywhere other than my Emotiva CMX-6, the noise is constant and louder in the left channel. Tried 5 tubes now, 2 of which are new production and all of which work fine in the Ember and Sunrise. |
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Post by luckbad on Feb 28, 2016 4:44:46 GMT
Is there a relatively straightforward way of adding auto bias to the Horizon III and Sunrise III?
A PCB below the existing one?
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solderdude
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Post by solderdude on Feb 28, 2016 17:09:28 GMT
Is there a relatively straightforward way of adding auto bias to the Horizon III and Sunrise III? A PCB below the existing one? You could duplicate the Ember autobias circuit and remove the manual bias circuit. May need some slight changes though. Will take quite some work and components being replaced + wiring though. |
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Post by luckbad on Feb 28, 2016 20:32:54 GMT
Maybe I could convince jhelms to add a $50 option to convert the Sunrise and Horizon to auto-bias. I'd definitely pay for it! |
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Post by luckbad on Mar 12, 2016 1:31:40 GMT
Update on the Horizon issue I was having: It was a bad left bias trimmer. Jeremy replaced it.
Quick question: I have the supercharger on it. If I use 6H6Pi tubes, it blinks for ~75 seconds, then goes into normal protection mode and is ready in ~2 minutes.
Is that normal because the tube draws so much current?
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solderdude
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Post by solderdude on Mar 12, 2016 17:03:33 GMT
That tube has approx 800mA heater current but it could be the inrush current is well over 1A.
When it blinks 2 or 3 times and then stays on it will be O.K.
However, 75 seconds is a long time for this.
Jeremy has experience with these tubes (I only have 300mA tubes).
Maybe he could chime in.
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Post by luckbad on Mar 12, 2016 18:59:07 GMT
Oddly, it only happens with legit old 6N6P and 6N6P-I tubes. New production 6H30Pi? No problem.
Sounds perfect, dynamic, and as expected after it stops blinking and the tube warms up fully. Really, A/B testing between the Horizon and Sunrise with identical tubes and either the Sennheiser HD650 or JVC HA-DX2000 I can barely tell a difference. Probably all mental, to be honest. The Horizon seems perhaps a tough more dynamic with the Sennheisers.
I'll just assume it's a quirk of the tube combo and close my eyes, pretending it never happens. If I ever experience issues with the sound, I'm sure Jeremy will help fix it.
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solderdude
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Post by solderdude on Mar 12, 2016 21:25:38 GMT
Oddly, it only happens with legit old 6N6P and 6N6P-I tubes. New production 6H30Pi? No problem. Sounds perfect, dynamic, and as expected after it stops blinking and the tube warms up fully. Really, A/B testing between the Horizon and Sunrise with identical tubes and either the Sennheiser HD650 or JVC HA-DX2000 I can barely tell a difference. Probably all mental, to be honest. The Horizon seems perhaps a tough more dynamic with the Sennheisers. I'll just assume it's a quirk of the tube combo and close my eyes, pretending it never happens. If I ever experience issues with the sound, I'm sure Jeremy will help fix it. In the good old days (where the NOS tubes come from) there was always a big transformer that supplied the high voltages and also the 6.3V glowing voltage. Heaters needed to get hot quickly and so most of these tubes have heaters that draw a LOT more current when cold compared to the 'hot' condition. For transformers it didn't really matter. They just sagged a bit and gave 4V or so but could deliver the needed current. When the heaters where on their temperatures the heater voltages would rise towards the 6 (6.3)V and all would be O.K. In these amps the heater supplies are DC converters/switching regulators that simply 'shut off' when over current is detected. After a short while they retry... and retry ... Because the heaters do have a chance to heat up during the short power bursts they get at some point the currents will become low enough that the circuit doesn't go in overload and the heater lights up normally. Newer tubes often have heaters that do not draw high start-up currents and still heat up quickly. |
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Post by luckbad on Mar 12, 2016 23:46:46 GMT
Just counted. Flashed 15 times before staying lit up. It's about 70 degrees F in the house so it's not terribly cool.
In the Sunrise III, it lights up immediately with the same tubes (I've tried multiple similar tubes).
Is the Horizon III with a supercharger still less able to provide current than a stock Sunrise III?
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