Showing 1 of 959 conversations about:
Eli35
585
Sep 19, 2018
bookmark_border
My unit worked well for two months, it sounded amazing with the HD6XX and Topping D30 DAC, specially after replacing for some NOS tubes. Problem is that after two months, the right channel suddenly stopped working for unknown reasons and Massdrop does not offer any warranty or support on this: I contacted support, it took them a week to basically say "sorry, you're screwed, good luck".
I've tried contacting the manufacturer, but according to my readings the company "Orphean Sound Audio-Video" does not exist anymore and/or there's not a way to contact them. 2 of the 3 founders of this company created "Yuking Audio-Video Lab" and developed the newer La Figaro tube amp, but there's no info around the former company, even their old website is down.
Now I'm basically stuck with a $230 paperweight, and some weird vintage light bulbs I can't plug anywhere else. I'll have to figure out how to repair my unit, if possible, by my own. If anyone knows a way to contact the manufacturer for a RMA/repair/whatever just let me know please!
Sep 19, 2018
Gallicdweller
15
Oct 10, 2018
bookmark_border
Why so negative - check out where you live for someone or a company that can repair valve/tube gear. In the process I'm sure they will be able to suggest modifications that will amaze you and I'm not talking about uber expensive mods either. Basically, this is a good h/amp which can be made to outperform.
Oct 10, 2018
Eli35
585
Oct 10, 2018
bookmark_border
Well, I'm negative because I paid for a WORKING product, not a almost-working pre-assembled DIY kit. I'm a computer engineer with some experience in electronics, basic soldering skills and access to a lab with minimum equipment, so hopefully I will be able to fix it, probably gonna try a few mods here and there after that, but that's not the point.
If I wanted to spend some time making my own tube amp, I've probably bough a Bottlehead Crack kit. I just wanted a working tube amp, got a defective one, no warranty/refund/repair/X was offered. That's why I'm upset.
Oct 10, 2018
Gallicdweller
15
Oct 10, 2018
bookmark_border
I do understand but Massdrop don't hide the fact that they do not give warranties on the gear they sell.
I would say you have an excellent opportunity to learn and get a real buzz out of repairing and improving your D/V. First do a continuity check to find out what component of the right channel has gone open circuit. The volume control is crap - you have many choices here - (1) you can use resistors to attenuate the sound level - (2) you could bypass it completely by providing volume control via an external pre-amp. On another forum it's suggested that the pre-amp circuit can be de-soldered and improve the sound (this is easy). I did this and it does improve the sound.
The output caps (3 per side) can be changed, with only 30uF per side it seriously restricts the cans that can be used with this amp. There are many examples of caps used on different forums. Be aware that changing these caps does mean a lot of de-soldering to remove the PCB these output caps are soldered to. You don't mention that you had a buzz with your amp - great but if you did, there are solutions.
You will be amazed at much better your NOS valves sound after these changes.
Oct 10, 2018
Motologist
73
Oct 10, 2018
bookmark_border
I was about to write something similar, great advice! All of these low cost Chinese made tube amps seem to be enthusiast products that require some user-side QC to achieve good results. Also, they all seem to have bad pots for some reason.
Oct 10, 2018
Eli35
585
Oct 11, 2018
bookmark_border
I know, they never said there was a warranty, my complain is about the support: they took a week to say "nothing I can do, sorry"; no contact to the manufacturer, no contact to any repair company, no options, nothing. If they could just tell me who can I speak to in order to get a RMA (as far as I know, any CE compliant electronic product HAS to get a minimum 1-year warranty, not 100% sure about that), or at least let me know who could fix this for me.
Thanks for the details, I'll definitely try those mods out. Yeah, I had some hum initially in one channel (don't remember which one), but it went away after some burn-in (removed power tube, unplugged RCA inputs and headphones, turned on for 6-8h daily for a week or so). Stock tubes had even worse hum, NOS were better but still there. It had a dead silent background last time it worked, and it sounded great with my HD6XX (and terrible with any low impedance cans, from planars to closed back dynamics, specially planars sounded dull and congested).
Would it sound better with high-impedance headphones if I replaced the output caps? I don't care about low impedance cans too much, because I know OTL tube amps have high output impedance and there's no point trying to drive low impedance headphones from it, they won't sound "good", right?. Also I have some other amps for driving low impedance headphones, so no big deal.
Thanks for your time, I appreciate :)
Oct 11, 2018
Eli35
585
Oct 11, 2018
bookmark_border
Yeah, right? My Little Dot I+ has one of the worst pots I've ever heard, if you're brave enough to change volume while listening to some bassy music, there's cracking everywhere. And sometimes it feels loose, like it should have more "resistance" to the force you apply to move it, but other times it doesn't... Just a bad, bad pot.
Oct 11, 2018
Gallicdweller
15
Oct 11, 2018
bookmark_border
The 30uF per side o/put caps are fine for high impedance cans, like the Senn 600/650s, it's just that the caps fitted are easily bettered. I was asked to write a review of the D/V and mentioned that one improvement would be a bigger chassis. There are some really good caps that could be fitted but no room. I'm lucky because I remove the bottom plate and sit the D/V on a slate box (no bottom or back plate) as on my Bada hybrid amps and use computer fans underneath to lower operating temperature of power resistors/mosfets and tubes. Check out via pinterest all the different mods for the D/V , especially the output caps. I'm also not at all sure that tube rolling every 5 minutes is a good idea with any tube amp. With the Bada PH12 h/amp and the PH32 power amp this was a total no-no - blown mosfets. Try one set of tubes once a day , leave the amp overnight, remove the tubes and fit another tube or set of tubes
I have to say that running any valve/tube amp without tubes for any period of time is not a good idea at all. Sometimes when testing a valve circuit it's permissible to have the amp on without tubes but only for as long as measuring particular points in a circuit - I wonder if this is the cause of your losing a channel?
Many have low impedance cans and use the D/V BUT after raising the values of the o/put caps considerably - again by using pinterest you will see along with photos of modded amps references to different forums that did the mods.
Fingers xed today - I have disconnected the volume pot and will be using a Stereo Coffee LDR volume/pre-amp kit I built to provide volume control
Oct 11, 2018
Gallicdweller
15
Oct 11, 2018
bookmark_border
The Valab 23 step att. fitted with SMD resistors would be a huge improvement @£19/$25, never heard anyone make a negative comment about them, just check out available space before buying
Oct 11, 2018
Eli35
585
Oct 11, 2018
bookmark_border
I know running a tube amp with any tubes removed is not a good idea at all, but I read a lot about this process before trying and a lot of people did that before without any issues, so I really doubt this could be the problem.
About tube rolling, I only replaced tubes once or twice, and never went back and forth. And last time I rolled was long ago, so I don't think that could be the problem. Do you think plugging-unplugging headphones while the amp is on (but not playing anything) could be the cause of my problem?
BTW thanks a lot for all the info, it's really helpful.
Oct 11, 2018
Motologist
73
Oct 11, 2018
bookmark_border
The pot on my LD Mk.II pretty consistently flips between sending more power to one channel over the other, excepting a couple points where it's balanced. Worst part? I've got a Milspec pot sitting in my basement that I think is correct size, I haven't been bothered to install it. I also had the rectifier blow up after a week, then I burned out the transformer trouble shooting it. But... the quirks kinda made me like it more. In my mind, your best option with respect to the D/V is to just open it up and ohm out the dead channel. These tube amps are pretty simple and the boards are spacious, whatever part you need is on Mouser somewhere.
Oct 11, 2018
Eli35
585
Oct 11, 2018
bookmark_border
Same here, the LD I+ channel balance is a joke at best, terribly inconsistent after changing the volume. Which pot did u buy for your mkII? Any suggestions for mine? I'll probably replace it sometime.
Oct 11, 2018
Motologist
73
Oct 11, 2018
bookmark_border
Mouser is probably the best place to find a replacement, you'll need to take some measurements to determine which one you need. A name brand Alps pot built for audio use isn't expensive and should provide good results.
I didn't buy my pot, my dad worked as an electrical technician for ATK when I was a kid; I've got a couple tool boxes full of board components from their various projects in the 80's/90's. He's the one who taught me how to work on electronics.
Oct 11, 2018
Eli35
585
Oct 11, 2018
bookmark_border
That sounds super cool, I'd love to have someone teaching me too, and some boxes w/ random components to tinker. Ok, I'll check Mouser, thanks a lot!
Oct 11, 2018
Gallicdweller
15
Oct 11, 2018
bookmark_border
Must disagree, I know a lot of commercial companies fit an Alps Blue as standard, that's not because they are good it just means that bought in quantity they are really cheap. Shunting an Alps Blue makes it into something far better. You can buy a small PCB on Ebay for use with the Alps and it makes it easy to shunt. Second best is the Valab.. A good volume control and good signal wiring are the first things to think about, second come the tubes - crap in - crap out. As you have the expertise, seriously think about shunting the pot, you can see how to do it on the World-Designs site.
Years ago I discovered for me the best pre-amp tube (6V) by a mile was the Tung Sol RP 6F8G. By the time I found out about these (thanks Skylab) the younger version - 6SN7 was outrageously priced. Many who have both say the 6F8G is a touch better, all these Round Plates sound damn good. I hav'nt shelled out for the very expensive o/put tubes for the D/V, the feeder tube has to be more important.
Oct 11, 2018
View Full Discussion