[Negatron]

Quote:

Originally Posted by Dept_of_Alchemy /img/forum/go_quote.gif That sounds like good news, the stock power tubes on the LDII++ are quite unstable and with the Russian upgrade 6S19P-V tubes even though the sonics improve quite a bit the amp itself still runs hot. EF92 and 5654 are quite rollable and gives a fair amount of room for tweaking the sound to your liking and doesn't cost too much to roll either.

No disrespect meant, but your comments about the instability of the LDII++ output tubes is slightly mis-understood. The unstable tubes were in the LDII+, where the supplied Chinese tubes arced to the cathodes upon turn-on and Russian tubes solved the problem. Generally the stock tubes in the II++ are pretty stable. I've had several of both amps and never saw a problem with the II++. The primary reason for replacing the tubes in the II++ with Russian tubes is simply that they sound better as you mentioned. I might add that the heat issue is just that the heater regulators use the chassis as a heat sink and so the heat is normal and not an issue of concern. I'm just trying to defend a wonderful and cheap little amp whose own native language is only Music.

 

[nkoulban]

I will stick to my LDII++, with the Russian power tubes and the Mullard driver tubes it sounds very musical and controlled yet still has the tube lushness. I still listen to it as my single ended rig and it works a treat as a preamp too. If LD release a valve balanced unit, then I'll go and buy it as I now mostly listen balanced. Oh and yes, when I have the LD II++ on I'll toast a few marshmallows to snack on while listening.

 

[vcoheda]

Quote:

Originally Posted by Negatron /img/forum/go_quote.gif No disrespect meant, but your comments about the instability of the LDII++ output tubes is slightly mis-understood. The unstable tubes were in the LDII+.

i agree with this. i never had any problems with the power tubes of the ++, including the stock pair.

Quote:

Originally Posted by nkoulban /img/forum/go_quote.gif If LD release a valve balanced unit, then I'll go and buy it as I now mostly listen balanced. Oh and yes, when I have the LD II++ on I'll toast a few marshmallows to snack on while listening.

if LD released a balanced tube amp, i would be game.

marshmellows. yum.

 

[Dept_of_Alchemy]

Quote:

Originally Posted by Negatron /img/forum/go_quote.gif No disrespect meant, but your comments about the instability of the LDII++ output tubes is slightly mis-understood. The unstable tubes were in the LDII+, where the supplied Chinese tubes arced to the cathodes upon turn-on and Russian tubes solved the problem. Generally the stock tubes in the II++ are pretty stable. I've had several of both amps and never saw a problem with the II++. The primary reason for replacing the tubes in the II++ with Russian tubes is simply that they sound better as you mentioned. I might add that the heat issue is just that the heater regulators use the chassis as a heat sink and so the heat is normal and not an issue of concern. I'm just trying to defend a wonderful and cheap little amp whose own native language is only Music.

Appreciate the cordiality, Negatron.

Perhaps it's my bad luck, the fact is I too have had both the LDII+ and the LDII++ and both have developed problems relating to their respective power tubes. To elaborate, the problems with the Chinese 4P1S on the stock LDII+ are well documented so I won't beat the horse again, as far as the 6C19P on the LDII++, I've heard several reports of them going bad within a few months of operation so I hope I didn't go overboard in saying that the Chinese 6C19P are relatively 'unstable'. Given the significant sonic increase that can be realized from switching to the Russian 6C19P-V and their apparent short tube life, I suspect the stock LDII++ power tubes were quite poorly made.

As far as the heat issue is concerned, it is true that the v-regs are bolted to the chasis to better dissipate heat and this does make the chasis hot, but every month or so I'd see reports of the v-regs themselves failing due to excessive heat, so evidently the amp is running too hot for the v-regs even when they are bolted to the chasis.

 

[Negatron]

Quote:

Originally Posted by Dept_of_Alchemy /img/forum/go_quote.gif Appreciate the cordiality, Negatron. Perhaps it's my bad luck, the fact is I too have had both the LDII+ and the LDII++ and both have developed problems relating to their respective power tubes. To elaborate, the problems with the Chinese 4P1S on the stock LDII+ are well documented so I won't beat the horse again, as far as the 6C19P on the LDII++, I've heard several reports of them going bad within a few months of operation so I hope I didn't go overboard in saying that the Chinese 6C19P are relatively 'unstable'. Given the significant sonic increase that can be realized from switching to the Russian 6C19P-V and their apparent short tube life, I suspect the stock LDII++ power tubes were quite poorly made. As far as the heat issue is concerned, it is true that the v-regs are bolted to the chasis to better dissipate heat and this does make the chasis hot, but every month or so I'd see reports of the v-regs themselves failing due to excessive heat, so evidently the amp is running too hot for the v-regs even when they are bolted to the chasis.

Any piece of electronics can have it's failure. And in fairness you seem to have been targeted by 'Murphys Law' an unreasonable amount of times. Also, I am not a supporter of the reliability of Chinese tubes, far from it. But the II++ did a pretty good job of overcoming the disaster of the original batch of II+ tubes.

EDIT: Most of the reg failures I have read about are the II+'s, which stem from the Plate arcing to the directly heated cathode (which is also the heater) which is driven by the V-regs. An arc - the reg pops.

I just hate to see a great entry level amp crossed off the list by people new to this Hobby. I don't think you do either, you have spoken well of the II++ at times. I would not hesitate to recommend it as a first stationary amp, tube or otherwise to anyone. Heck, I gave one to my Sister. (w/Russian tubes

)

Just remember, LD had a long road to overcome the disaster of the first tubes and their excellent service saved a Company that benefits all of us, so we need to be careful they are not un fairly labeled for past events. 'Nuff said.

 

[Angry]

Stolen from Little-Tube

 

[Dept_of_Alchemy]

The Mk2 looks promising. They even bothered to clean the resin off the PCB.

The inclusion of a fuse in the power supply is also a nice improvement, although the tubes still look shady as heck.

Looks like it's gonna sound better than the LDII series, can't wait.

 

[Dept_of_Alchemy]

Quote:

Originally Posted by Negatron /img/forum/go_quote.gif I just hate to see a great entry level amp crossed off the list by people new to this Hobby. I don't think you do either, you have spoken well of the II++ at times. I would not hesitate to recommend it as a first stationary amp, tube or otherwise to anyone. Heck, I gave one to my Sister. (w/Russian tubes )

Make no mistake, I think the II series were great amps and will surely go down in head-fi history as a benchmark by which future budget tube amps will be judged. I too would not hesitate to recommend the ++ to anyone who are new to this hobby, that said, I do feel obligated to point out the few flaws that I see plague the II series, namely the reliability concerns with the + and the far-below-par quality of the stock tubes on the ++.

 

[mwallace573]

Quote:

Originally Posted by Angry /img/forum/go_quote.gif Stolen from Little-Tube

They've definitely moved some stuff around on the board since the 2++, so it's not the exact same internal design, though it looks very similar. The switches to change the gain are a nice addition. Anybody else notice that on the board it says Little Dot MK I/II? Are they using the same board for two amps?

 

[vcoheda]

yeah. the PCB looks a little different, but otherwise things look pretty much the same. the gain switches instead of jumpers are a nice addition, but nicer still would have been the ability to change the gain w/o opening it up. the numbers on the volume control look bad. tacky. also, it would have been nice to have a neutrik locking jack for the headphones. and what is the tube complement for this amp. same as the ++? the driver tubes look different.

 

[Penchum]

Quote:

Originally Posted by vcoheda /img/forum/go_quote.gif yeah. the PCB looks a little different, but otherwise things look pretty much the same. the gain switches instead of jumpers are a nice addition, but nicer still would have been the ability to change the gain w/o opening it up. the numbers on the volume control look bad. tacky. also, it would have been nice to have a neutrik locking jack for the headphones. and what is the tube complement for this amp. same as the ++? the driver tubes look different.

Well, if David Z was correct (and I'm assuming he was), then it should except both families, EF92s (and equivalents) and the 5654s (and equivalents). The numbers on the volume control will take me some time to get used too. I wonder if there is room to modify it to accept a Neutrik locking jack? I'm very fond of those too!

 

[Dept_of_Alchemy]

Quote:

Originally Posted by Penchum /img/forum/go_quote.gif Well, if David Z was correct (and I'm assuming he was), then it should except both families, EF92s (and equivalents) and the 5654s (and equivalents). The numbers on the volume control will take me some time to get used too. I wonder if there is room to modify it to accept a Neutrik locking jack? I'm very fond of those too!

Not a big fan of locking headphone jacks myself (makes sense for microphones, but what's the point in paying more for the opportunity to accidentally pull your amp off the shelve?) My vote goes to improving the volume control pot, the stock ones are quite flimsy and non-linear at low volumes.

 

[Penchum]

Quote:

Originally Posted by Dept_of_Alchemy /img/forum/go_quote.gif Not a big fan of locking headphone jacks myself (makes sense for microphones, but what's the point in paying more for the opportunity to accidentally pull your amp off the shelve?) My vote goes to improving the volume control pot, the stock ones are quite flimsy and non-linear at low volumes.

I guess I'm not understanding you clearly (nothing new for me these days) when you say "quite flimsy and non-linear at low volumes". My LDII++ has no play in it and the scale of volume increase is pretty much steady up too "ow that's too load". I know some folks had trouble with the stock volume knob's plastic interior wearing, but I changed mine to a nice heavy gold one that screws down, long ago. Are we talking about the same stuff??

The only reason I like the locking jack is to keep from unplugging accidentally. I found out with my MKIVse that the headphones will come off my head long before the unit decides to slide anywhere, so I assumed the weight of the LDII++ would bring similar results. Ow and I almost forgot, I have both units sitting on some of that anti-slip material you can buy for shelves and such. I'm sure that helps more than I think.

 

[Penchum]

Well, I'll post my external mods to my LDII++ here. Don't laugh too hard about the white dock for my black Creative Vision sitting next to it. I got the dock on clearance for $7! Ow and under the LDII++ is a non skid material surrounded by aluminum foil, to reflect the heat away from the wooden shelf. It actually works!

I'm still looking for the smaller tube guards for the driver tubes. They are very hard to find, and if anyone knows where to get them in any color, please let me know.

 

[NeObliviscaris]

I wanna get one of the older Little Tubes, hopefully they come up cheap since the MK series is out!