I’m currently on the lookout for a budget tube amp to pair with my Fiio K11. I know that 99% of IEMs aren’t hard to drive at all and wouldn’t need an amp but I kinda wanna try out tube and get a feel on how it would affect the sound of my IEMs. Since it’s just an exploration phase at this point and I don’t use any headdphones, I’m rather unwilling to spend too much money on it in case I don’t really enjoy it.
The top shout I have seen is Apos Gremlin, which is sold for 120$. Price wise its ok for me but its open design worries me since my apartment tends to get dusty really quick. I also have found some cheap chinese tube amps on ali from Nobsound/Aiyima/Douk Audio but can barely find any reviews about them. I guess up to 100 ish € is ok budget for me, cheaper better ofc.
Do you guys have other recs regarding this topic? Thank you for the help in advance!
Isn’t the Gremlin full balanced in and out and the K11 SE out only?
Xduoo MT 602 is a fun little hybrid amp with plenty of tube rolling options and SE, I’ve got the MT 604 which is pretty much the same but the balanced version and I use it to drive IEMs
I’m not really well versed with sources yet, so correct me if i’m wrong, but would it be possible to connect the K11 and the gremlin apos with, for example, RCA to 4.4 balanced or RCA to XLR cables? Or is this not recommended for the same reason a 3.5 mm to 4.4 mm adaptor is not recommended?
I will take a look at the Xduoo MT 602. It looks nice and definitely falls in my budget rn. Thanks for the rec!
I can run my DX300 via a DD 4.4mm to 1/4 inch jack to my Little Dot MKII just fine I wouldn’t recommend going the other way…So I think balanced to SE is ok but SE to balanced not so…
wouldn’t rec tubes with IEM unless you’re using it to preamp another amp
they’re too low impedance for pure tube amps to run properly (maybe could use impedance adapter) and will pick up any noise the tubes/chain make
hybrid tube amps could have mixed results but still not ideal imo
Not all IEMs are low impedance. Many are but certainly not all. I have a set that are 60Ω
@potatopotata To avoid unintentional frequency shifts, the rule of thumb is 8:1 ratio meaning the load/IEM/HP/speaker impedance is 8 times the output impedance of the amp.
A higher ratio is usually ‘better’ as it increases the amps control (damping) over the driver…but IEMs are often very sensitive AND very efficient so the inherent noise of the electron flow in vacuum tubes can be quite apparent at low volumes but again it depends on the specific IEMs measurements.
Over the decades of tube output stages a bit of hiss was normal and really doesn’t affect the enjoyment of music at normal listening volumes but then solid state changed things by being exceedingly quiet, and often sterile, clinical. We’re past the bad parts now; for a long time though. For many who’ve only ever heard the clean output of non-tube outputs are turned off by a touch of hiss/noise but in my experience there is some magic in that noise only provided by the organic nature of tubes. Specifically the 2nd order harmonics. The level of hiss and 2nd harmonics varies greatly between different tube types and different tube designs within the same family.
I built several speaker systems with tubes in preamp and/or amp stages (mostly input stages with SS output stage) over the decades but currently only have a single amp with NuTubes in them. For the money and my opinion and experience, the Apos Gremlin is fantastic and should work great with your K11…although to use with IEMs you may not be able to get the volume low enough. The Gremlin pumps out a couple watts though it does have an excellent dual pot volume control. You can further attenuate using the K11 control but at some point it will be affecting the resolution. Best to run full scale from the K11 and adjust at the amp…
The dust really isn’t an issue for the Gremlin. The top keeps most out but the little devil really needs the open chassis to breathe. Just blow it out from time to time with a blower of your choice.
There are gobs of variety of tubes the Gremlin supports 6/7V and 12V. I would avoid the ‘upgraded’ tubes from Apos and put the money into the plentiful NOS and new tubes out there.
