Curious how the Russian Military 6SN7 (ie 1578) works with the Crack? Anybody know? Since I have some NOS 1578's here that have less than 100hrs on them, I really need to find some way to use them! :)
Recent Images In This Thread
Related Forum Threads
- [Review] Ortofon HD-Q7 Last post on 1/16/11 at 11:59pm in Headphone Amps (full-size)
- All Aluminum Bottlehead Amp.... Last post on 11/10/12 at 5:17pm in Headphone Amps (full-size)
- Schiit Valhalla and the overly bright mids that are masking the bass Last post on 5/24/12 at 1:40pm in Headphone Amps (full-size)
- Do I even need a headphone amp (Tesla T1 / Yamaha home cinema amp) Last post on 11/30/13 at 7:52am in Headphone Amps (full-size)
- Just looked at the Bottlehead amps and... Last post on 10/9/11 at 5:25am in Headphone Amps (full-size)
Diy Beginners Guide
Last edited: 7/22/13
- Headphone ImpedanceLast edited: 8/18/12
Just some background stuff before the review...this is the second source i have owned dedicated to music (i.e not listening to music off my iphone) so i don't have much experience with high end...
I recently got the AK 100 II after dabbling with a phone based stack. Alternate setup: Samsung Galaxy S5 FIIO E18 + PowerAmp Pro (Cost: 2.99€) + iSyncr (Cost: 3.99€) + Stream to...
After an extensive search online for a replacement for my very good Schiit Bifrost, I settled on the Dacmini, in part from comments here on Head-Fi, and the fact that Stereophile has had it as a...
DUNU DN-2000 Quick Review Full Review at http://www.head-fi.org/t/728105/dunu-dn-2000-review Thanks to DUNU for the sample. Brief: DUNU take’s it to the top. Price: US$316 or £186...
Ok first I need to say that I'm not an audiophile, and I use this site mostly for help than giving advise whit that told I will continue I've owned this headset for more than a year and they...
- Headphone Impedance
Crack;Bottlehead OTL - Page 103
Gear mentioned in this thread:
There was a discussion on the BH boards a while back about how 6sn7's might not be an ideal match for the crack due to PS circuit. My recollection is that the crack delivers ac to the tubes' heaters, whereas 6sn7's should ideally be getting dc - to say nothing of the possible noise introduced by the adapters.
At the time, this was enough to send me hunting 12bh7's instead - my favorite of which is a 1959 Tung Sol. But I confess I am still curious to hear how a good 6sn7 sounds.
I'm getting a lot of noise through my Crack when I attach a USB DAC to it. I hear the noise regardless of whether music is playing. Pretty sure it's the USB because when I unplug the cable from my computer it completely disappears. I don't get any noise from the USB DAC when I use my M-stage as an amp though.
When I use an E10 as an SPDIF interface and output coax to my DAC, it's dead quiet. When I input coax (SPDIF) from my Oppo 980H CD player it's dead quiet as well. However, when I use the E10 as the DAC and output it's analog line-out directly to the Crack, I hear the noise again.
Do I just have a noisy USB socket on my computer, or is it the cable, or is the DAC not filtering out the noise?
Or could it be that the braid on the wires from the RCA inputs to the pot in the Crack wasn't done well enough?
Any ideas on why I'm hearing so much noise?
Edited by EraserXIV - 3/5/13 at 12:25pm
Do you get the noise when plugging in an mp3 player? What about running the laptop from battery?
Is the noise like a low hum, or more like static/white noise?
My initial guesses would be noisy usb socket and/or power supply, or a ground loop.
It's like static/white noise that seems random but does have a slight pattern to it (if that makes any sense). It seems like it has a cyclic pattern where it gets louder and softer at intervals without me touching anything on the amp, DAC, or computer. I haven't tried an mp3 player or unplugging the laptop, will definitely try that when I get home later tonight.
Edited by EraserXIV - 3/5/13 at 1:31pm
So that's an issue with the power supply to the laptop? I guess this can be tested easily by unplugging my laptop, will do that later today.
Just curious, why does this noise not transfer when I use an SPDIF interface in the middle of the chain?
Also, if it is the switching power supply from the laptop, are there any ways to fix the noise? I don't really mind using the SPDIF interface, but I like keeping the chain as simple as possible and if I can avoid it, the better. Will certain DACs filter the noise better than others? How come the M-stage didn't pick up the noise?
The spdif is essentially isolated from dirty power noise.
It could be the Matrix has better power or input filtering, or is configured in a way that happens to reject that particular sort of noise.
To "fix" the laptop... well, you could get a better power supply, or just run off battery (maybe a bigger battery, or external battery pack). You can also try a ground loop isolator. They're cheap... like $10 from radio shack. It looks like a regular RCA interconnect with a block in the middle (typically about the size/shape of a D cell battery).
So I think the noise I was hearing is a combination of a couple things. I switched power supplies on my laptop to one with a 2 prong plug and it reduced the noise a lot. At first, I thought it completely eliminated the noise, but when I turned the pot up on the Crack past 12 I started hearing it again (albiet only slightly). Before I switched supplies I was able to hear the noise with the pot completely turned down to 6 (and it was much louder than the new supply past 12).
With the pot turned up to 12 using the new power supply, unplugging the power supply altogether slightly reduced the noise. The noise doesn't completely disappear unless I unplug the USB from my laptop. I'm thinking it's a combination of noise from the power supply (ground loop?) and a noisy USB port. I do most of my listening between 8-10 so it's not really an issue for me I guess. I only barely hear it at 12. I might still toy with the idea of the SPDIF interface though as it completely eliminates the noise.
Any ideas on what a powered USB hub would do?
Edit: this video gave me the idea to switch to a 2 prong plug power supply: http://www.youtube.com/watch?v=jSA2F1AwboU
Edited by EraserXIV - 3/5/13 at 10:04pm
The powered usb hub *might* help, but no guarantee. You're better off with the unearthed power supply or a signal isolator.
Just curious, is he describing jitter or is it simply dirty power from the USB port?
There's no way any jitter would cause noise that bad. That'd be an utter failure of the device right there.
- Crack;Bottlehead OTL
Gear mentioned in this thread:
- › Lets Talk Metal 19 seconds ago
- › AKG Q701 or Philips Fidelio X1 1 minute ago
- › Havi B3 Pro-1 Impressions Thread 3 minutes ago
- › iBasso DX90. Dual Sabre, 1st page to reformat latest FW download &... 3 minutes ago
- › D.C. Area Meet (Saturday, July 26th, 2014) - part of CanMania @... 3 minutes ago
- › looking for a pair of headphones that can handle most edm 5 minutes ago
- › Bose Sues Beats for Patent Infringement 5 minutes ago
- › What Are You Listening To Right Now? -New thread, new rules. Please... 6 minutes ago
- › 「Official」Asian Anime, Manga, and Music Lounge 7 minutes ago
- › Show us your Head-Fi station at it's current state. No old... 9 minutes ago
- › Apple iPod classic 160 GB Silver (7th Generation) NEWEST MODEL by fluffyberry
- › Astell&Kern AK100II High Resolution Single DAC Audio Player... by CasperBxl
- › CEntrance DACmini CX by joespride
- › DUNU DN-2000 Hybrid 3 way earphone by mark2410
- › Astro A40 Audio System - White by MaxiMarciano
- › Logitech Z553 2.1 Speakers by Nada190
- › Future Sonics mg5pro 10mm Ear Monitors by Kunlun
- › AKG K812 by jk47
- › Sennheiser Grado Hybrid a.k.a. SennGrado by fleasbaby
- › T-Peos Altone200 by ClieOS
- › Audio Connections between components --...
- › Head-Fi Buying Guide (Introduction)
- › Head-Fi Buying Guide (Over-Ear Headphones)
- › Head-Fi Buying Guide (Over-Ear Headphones) 2
- › Head-Fi Buying Guide (Over-Ear Headphones) 3
- › Head-Fi Buying Guide (In-Ear Headphones)
- › Head-Fi Buying Guide (In-Ear Headphones) 2
- › Head-Fi Buying Guide (In-Ear Headphones) 3
- › Head-Fi Buying Guide (Gaming Headphones)
- › Head-Fi Buying Guide (Exercise Headphones)