[vlach]

That's a rather vague answer, I'm not even sure how to interpret it. Of course i don't run the QS at full volume, who would??

 

[luishi5000]

I interpreted it as running the DAC at full volume.

Seems like we all agree that it seems to work fine at 2v. It certainly doesn't seem like it's lopping the tops of our waves off.

 

[Tomm11]

I interpreted it as running the DAC at full volume.

Seems like we all agree that it seems to work fine at 2v. It certainly doesn't seem like it's lopping the tops of our waves off.

No, pretty sure Mike means running the amp at full volume. It will make full, undistorted power with 1 - 1.5 volts input ('input sensitivity"). The amps volume pot is essentially controlling the amount of voltage allowed into to the rest of the circuit.

As a rough example ... if you fed the QS with a 1Khz tone at 2 volts the amp would clip at the output with the volume pot wide open. If you fed it with a 1Khz tone at 1 volt (or maybe up to 1.5 volt since Mike gave a range of 1 - 1.5v) the output should be clean with the volume wide open. With the 2 volt input, the output is going to be clean with the volume pot turned down somewhere below wide open. Thus Mike's comment, "Yes, but you don't have to run it at full volume".

edit to add that the downside is that with sensitive headphones (or especially iem's) you may have too little play with or a "touchy" volume control if the source is kicking out 2 volts (or more) with the input sensitivity being 1 - 1.5 volts. Personally, I haven't had any issues.

 

[luishi5000]

Thanks for clarifying! Good to know that 2v is in the clear.

 

[jamato8]

No, pretty sure Mike means running the amp at full volume. It will make full, undistorted power with 1 - 1.5 volts input ('input sensitivity"). The amps volume pot is essentially controlling the amount of voltage allowed into to the rest of the circuit.

As a rough example ... if you fed the QS with a 1Khz tone at 2 volts the amp would clip at the output with the volume pot wide open. If you fed it with a 1Khz tone at 1 volt (or maybe up to 1.5 volt since Mike gave a range of 1 - 1.5v) the output should be clean with the volume wide open. With the 2 volt input, the output is going to be clean with the volume pot turned down somewhere below wide open. Thus Mike's comment, "Yes, but you don't have to run it at full volume".

edit to add that the downside is that with sensitive headphones (or especially iem's) you may have too little play with or a "touchy" volume control if the source is kicking out 2 volts (or more) with the input sensitivity being 1 - 1.5 volts. Personally, I haven't had any issues.

That is fairly normal. You can clip most any amp under the right/wrong situation.

 

[Tomm11]

Thanks for clarifying! Good to know that 2v is in the clear.

No problem.

 

[Tomm11]

That is fairly normal. You can clip most any amp under the right/wrong situation.

Yep.

 

[luishi5000]

I got the Toroid isolation transformer (isobox 900va), it definitely made some improvements.

Without it I would hear noise when I got to 2 o'clock (not that I would ever listen that close).

With it I can crank the dial front to back and it's dead silent, also my very quiet 60hz hum is completely gone.

Glad it's doing something, I was skeptical after reading all the conflicting info.

That said, my tubes occasionally still have the high frequency buzzing, so either something is still getting through or is somehow caused by the tubes themselves. Playing the tube lottery has been the best help so far, just one of my tubes needs a little help now. Getting a set of quads and will pick the best among. Wish me luck!

 

[gefski]

Regarding the earlier comments about 2V out to the QS input being too “hot”, I’ve got a couple pairs of simple Harrison attenuators to try. The 6db moves my normal vol knob listening position from 9:00 to 11:00, so I certainly like the improved range there. I’ll listen for a week then remove them and see if I can determine if they created any audible degradation in sq. Initially, I don’t hear any.

 

[Kevin.T]

I just acquired this beast of an amp in a trade (along with the supremely enjoyable Auteur Classics). I am having a bit of noise issues with the amp using the Auteur, and it's almost exactly like luishi5000 describes!

I hear a low level buzz in the left channel. Just like luishi5000, the buzz is louder at the very beginning of the volpot, then quiets down around 8-9 oclock. Maxing out the volpot brings the noise back (but would make me deaf instantly with music playing, so a non-issue).

I can also hear the radio! Using my Modi 3E, I can actually hear it a lot. Using a DAC with a more robust casing, it is significantly reduced, but I can still hear it faintly occasionally. However, the buzzing is more audible, and is the main thorn in my side right now.

I also have a pair of 5751 tubes on hand. Rolling in the 5751, all noise is slightly reduced (along with the gain). Buzzing is reduced (but still audible), radio is practically gone. However, since the builder of the amp discourages use of 12AX7 alternatives in the QHA (including 5751), I would like to be able to use 12AX7 ideally.

The unit is positioned on my office desk, above my PC (the PC is under the desk). Moving my listening station to another room is not really an option right now (limited space in my living situation).

I have already tried some things, with no success in eliminating the buzz:

- Switched the sides on all tubes (EL84 and 12AX7). The buzzing stays on the left.
- I'm using a Morley Hum Exterminator. It doesn't seem to make much of a difference in my situation (still have the buzz with it on).
- I tried plugging the amp in its own wall socket; I tried plugging it in the power bar with other electronics; I even tried running a power cable to another room on an unused outlet... the buzz is still there in all cases.
- I tried moving the amplifier on the opposite side of my desk (moving it a couple of feet away from the PC). It made no difference.
- I have made sure that Wifi is turned off on my PC (and I disconnected the antenna). I'm using a wired network connection. Still hearing the buzz in the left channel, not sure it made a difference.
- Moving my cellphone towards or away from the amp doesn't affect the noise.

If anyone has any tips or ideas, I am all ears! I looove the sound of this amplifier with the Auteur Classic: incredible midrange and out of head experience. If I could get rid of this small noise issue, I would be in heaven!

Hey guys, just wanted to give a quick update on this "left channel hum'" issue I had. It was actually a blown resistor in the amp!

I did a lot of troubleshooting, including bringing the amp to another building. I got the very same hum in the other building. That's when I figured it had to be something inside the amp. I had already looked inside before, too look for anything "obvious". I guess I didn't look hard enough. After looking (much) closer, I found a small resistor attached to the left EL84 socket that was quite a bit darker than the other ones. I wrote to Mike, and he confirmed that that resistor works to balance out hum, and that it indeed looked blown. He told me replacing it would fix my hum problem. I had the amp serviced locally to change the resistor, and my amp is now hum-free! Only clean and smooth sound from now on.

 

[luishi5000]

Hey guys, just wanted to give a quick update on this "left channel hum'" issue I had. It was actually a blown resistor in the amp!

I did a lot of troubleshooting, including bringing the amp to another building. I got the very same hum in the other building. That's when I figured it had to be something inside the amp. I had already looked inside before, too look for anything "obvious". I guess I didn't look hard enough. After looking (much) closer, I found a small resistor attached to the left EL84 socket that was quite a bit darker than the other ones. I wrote to Mike, and he confirmed that that resistor works to balance out hum, and that it indeed looked blown. He told me replacing it would fix my hum problem. I had the amp serviced locally to change the resistor, and my amp is now hum-free! Only clean and smooth sound from now on.

That's excellent news! I wonder how it got blown to begin with.

Update on my intermittent high frequency buzzing:

After now going through 5 pairs of Gold Lion EL84's... I have finally found 2 tubes among all 10 of them which don't seem to have intermittent buzzing.

It makes me wonder if it's really the tubes or I have something slightly wrong with my resistor as well that takes an especially "good" tube to fix.

 

[JacquesCustodian]

Hi folks, writing here as I don't seem to have posted enough to access the Classifieds WTB feature.

I am interested in buying the Quicksilver headphone amp, preferably from someone within the EU. If you are thinking of parting ways with yours, or know of someone, I'd be happy to hear from you

 

[tamleo]

Hello,
Does anyone here compare the QS vs the Eddie Current Zana Deux SE? tks

 

[mattiastomas]

After reading thru this thread I ordered the Quicksilver amp today! Called Mike and they had 1 left and ships out today! Can't wait! Heard nothing but good things about it

 

[tamleo]

So I emailed QS about the backorder and way to buy their amp. They replied me with one short sentence without any greetings or whatsoever??! Did they consider me as a customer or ? Idn if I should expect a refined and sweet sounding amp from that company..