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Post by Deleted on Sept 19, 2015 12:03:12 GMT
Mark, with something really sensitive, if I want the tubey sound, I put an adjustable resistor on the output, turn the volume off and adjust the attenuation to get rid of any hiss there, before I turn up. Just a cheap thing but it works as well for those portable radios that hiss with no volume. Gordon, it's amazing what reading the instruction book does, isn't it? The Polaris is actually a lot quieter than the Ember but that might also be my reluctance to play around with tubes and hear these enormous differences!!  My hearing isn't so good at the top end but I've never heard any hiss on my Ember. I only have 4 tubes but all are silent. |
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solderdude
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Post by solderdude on Sept 19, 2015 12:33:48 GMT
These attenuators do exactly the same as a higher output R setting.
It's just a series resistor.
The headphone attenuation adapter I was talking about lowers the output resistance, for some headphones (especially MA IEMs) a low output R is essential.
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Post by Deleted on Sept 19, 2015 23:33:09 GMT
Hi Frans, when you say the attenuators do the same thing as the high output R setting does that also mean the same dramatic increase in output R?
I recall from the info I was able to get from iFI that you surmised that the output R of their attenuator is around 1 Ohm, which presumably makes it better suited to low impedance headphones & IEMs than the Shure & Sennheiser attenuators that were mentioned above?
My grasp of audio electronics is sketchy at best but would you mind explaining something? You mentioned that if you were building an attenuator you would use the Mid R setting and then lower the output R to an acceptable level. Is there a benefit to using Mid R rather than the Low R setting which presumably already have a suitably low output R e.g. less noise, better SQ, more tube flavour retained?
Thanks.
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solderdude
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Post by solderdude on Sept 20, 2015 6:54:35 GMT
It depends on who made the attenuators. the iFi one is indeed low impedance. Most of the (cheaper) and variable options is just a series resistor. It could be possible they have some sort of 'L-Pad' in there but is unlikely because of the required power rating. You can build a low output R attenuator in 2 ways: HERE is more info on how to make 'proper' attenuators yourselfUse 4 resistors and drive that from a low output R amplifier capable of delivering power in a low impedance. In such an adapter there are 2 series resistors and 2 parallel resistors. The series resistors will be in value between 22 and 33 Ohm. You can also build a version with just 2 resistors and use the series resistors of the amplifier. This will onloy work when it has an output R of (roughly) the same value as the series resistor mentioned above. The mid setting of all garage 1217 amps have about 35 Ohm as output R so can be used that way. Small caveat: you cannot use this adapter on low output R amps and will give too much attenuation for H output R amps. In that sense using 4 is MUCH more universal applicable as one using 2 parallel resistors and better than those having only 2 series resistors. |
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Rabbit
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Post by Rabbit on Sept 20, 2015 9:32:03 GMT
Hi Frans, when you say the attenuators do the same thing as the high output R setting does that also mean the same dramatic increase in output R? Thanks. The cheap one from Shure one is variable and includes a 'volume' type dial, so you can set the resistance to just the exact amount that you need to get rid of the hiss. So it doesn't need to be at 120 ohms output if hiss has already gone before you reach that point. That way, sound differences are at least minimalised I guess. |
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Post by hifidez on Sept 21, 2015 13:36:51 GMT
Hi Frans, when you say the attenuators do the same thing as the high output R setting does that also mean the same dramatic increase in output R? Thanks. The cheap one from Shure one is variable and includes a 'volume' type dial, so you can set the resistance to just the exact amount that you need to get rid of the hiss. So it doesn't need to be at 120 ohms output if hiss has already gone before you reach that point. That way, sound differences are at least minimalised I guess. This is 'cheap and cheerful' which is my normal habit I suppose. It used to be about 7 quid, www.maplin.co.uk/p/headphone-extension-cable-with-volume-control-l43afI use it for the same reason e.g. bedside radio has high background hiss hiss when used at low volumes over headphones. Turn radio to zero, use in-line volume control to lower hiss level until hiss can't be heard, turn radio back up. Also use it to reduce output from my NX1 as its volume control is poorly balanced at very low levels - which I use at night. |
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dpump
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Post by dpump on Sept 21, 2015 17:09:00 GMT
I have my Ember V1 listed For Sale on Head-Fi if anyone is interested.
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solderdude
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Post by solderdude on Sept 21, 2015 18:25:56 GMT
Where are you located ?
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Post by musicman on Sept 23, 2015 1:50:08 GMT
Add says he is from North Carolina. $300.00
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Post by tunkejazz on Sept 23, 2015 11:48:37 GMT
Add says he is from North Carolina. $300.00 A bit steep for me, although he includes some tubes. I cannot decide for a second Ember or a Polaris for the system that I want to have at home. A good second hand deal could help to decide :-) |
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Rabbit
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Post by Rabbit on Sept 23, 2015 16:34:26 GMT
Go Polaris!!! Especially if you already have an Ember. I often use the Ember wither higher impedance headphones and Polaris with lower. Lower noise floor. Similar in sound. More options for power output. It's extremely good!!!!!! |
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dpump
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Post by dpump on Sept 23, 2015 17:00:33 GMT
I have my Ember V1 listed For Sale on Head-Fi if anyone is interested. I am in North Carolina. Since I have a Solstice and a bunch of other amps, I need to downsize a little. The Solstice lets me use 12SN7 tubes which I have quite a few that I bought for a preamp I had years ago, so I decided to keep it and sell the Ember. I also have some other 6SN7's if there is another type you would like. Don't have any Tung-Sol round plates or Sylvania 'Bad Boys', but older RCA's and others if that makes a difference. |
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howie
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Post by howie on Sept 23, 2015 18:09:34 GMT
Add says he is from North Carolina. $300.00 A bit step for me, although he includes some tubes. I cannot decide for a second Ember or a Polaris for the system that I want to have at home. A good second hand deal could help to decide :-) I should be able to do that comparison at the weekend as I return from Spain on Friday, but if you are keen to make a decision before then I would agree with Ian that the Polaris will give you extra listening flexibility to add to your existing Ember and I don't believe you will be disappointed with Polaris. Polaris shares the characteristic musicality of all G1217 amps with engaging sweet clarity and excellent flexibility to fine tune the sound. |
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Post by walbum4262 on Sept 28, 2015 20:47:58 GMT
Hi all I'm a first time poster here even tough I have been in contact with Frans trough the Danish head-fi site for other reasons  I have read trough most of this thread but I must admit I don't remember where I saw some of the solutions for my problem. So my apologies if this has been answered. I just got my hands on this beauty of an amp and I must say that I'm pleased with it so far with my modded fostex t50rp and he500 With it I got a matched pair of kenrads 7193 and the Frankenember  And also a Shuguang CV181z tube  With the cv181 I barely pick up any noise but with the kenrads I do get quite a lot of noise, when I touch the RCA input plugs I am able to lower the hum some but not completely any advise on what to do here as I can't sit and hold my finger on the input Best regards David Walbum |
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solderdude
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Post by solderdude on Sept 28, 2015 21:44:32 GMT
Hi David, Welcome to the forum.
The Ken Rads have some mighty big antennae on the top of the amp.
That may be a reason for picking up interference.
It is an open frame amplifier and obviously susceptive to all kinds of interference when those unwanted signals are high enough.
Sometimes re-routing cables or even mains cords could 'cure' the problem.
WiFi, cell phones, wireless house phones etc in the vicinity could also cause these problems.
Sometimes grounding helps (running a wire from the RCA screen to a real ground such as waterpiping or central heating).
It is very difficult to say what's exactly causing it BUT many people have reported not having similar issues with this setup so it should be possible to get it right.
It will be a matter of experimenting.
Start with switching off or removing wireless stuff.
Try moving the amp to another location and see if that helps.
Sometimes moving it 30cm could be enough.
Perhaps re-arranging cables is an experiment worth doing.
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