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Little Dot Tube Amps: Vacuum Tube Rolling Guide - Page 235

post #3511 of 6832

Hi All,

 

I'm thinking of a suitable headline for this experience; don't know how to word it:

 

Scary Moment in Tubeworld

 

Disaster in the Mancave

 

Listening Room Filled With Acrid White Smoke (exaggeration)

 

Anyhow, I was sitting there and doing some paperwork with the music on fairly low volume listening via speakers to Harry's Happy Four from 1925.

 

Suddenly a pop, the music cuts out, comes back and another pop! Silence. I turn around to see what's going on. White acrid smoke surrounds my receiver and the Little Dot! I immediately switch of all power. Oh no - did I finally kill my beloved Little Dot? Different thoughts flash through my mind - how much is it going to cost to ship it back to China? How will I manage without the beautiful music?

 

Slowly I try to find out what's wrong. Wait a second; the Little Dot works fine with headphones. Like wise the receiver works with phones, but no sound from the speakers. Where is the problem?

 

Call my retired engineer friend. I take the cover off the receiver - no visible signs of something burning. He tells me that the best way to find out is to use your nose and smell where the acrid smoke comes from. A smell test of the Little Dot does not tell anything. Now the receiver:

Yep, it does have a bad electrical burnt smell. I finally locate it to one side of the receiver. My friend tells me that it could be anything; perhaps a blown capacitor due to a faulty transistor. I call the manufacturer - they can't tell me anything over the phone. I find out that it is going to cost me around $200 for shipping and repair. Ouch...

 

The effects of AMWS start to set in. I can't even listen to the Little Dot because all the wires go through the receiver, and I am advised not to turn on the receiver since it could be dangerous.

Acute Music Withdrawal Syndrome - What am I to do?

 

My friend offers to take a look tomorrow but does not know how long it will take to get the parts etc.

 

Suddenly I remember that I have an old 1980's Sony receiver sitting in the house that one of my kids gave me some 15 years ago after the grandchildren had wrecked the stereo console. (Sony Slave - r u reading this?)

 

To make a long story short, it is a Sony Integrated Stereo Receiver TA-AX530. 110 Watts/channel. I worry about the warning of not using a DC (Direct Current) Amplifier. But it says Integrated, not DC. On the back are jacks for inserting an equalizer, and I plug in the LD into this circuit. Turn everything on, and then flick the equalizer switch on, ready to cut the power if something explodes.

 

Success! Whew, don't have to suffer from AMWS. Four speakers are working, but I don't know how to connect my two subs.

 

 


The sound is fairly good - warm beer vs champagne. I am happy again....

post #3512 of 6832

I just saw a deal on a Little Dot MK III appear in the F/S section within the last 50 minutes.  Complete with box, good shape, etc.  $160, shipping included in price.  I don't have any affiliation with this seller.

 

I checked the Little Dot sites for this model and it runs $199 + shipping expenses.

 

Enjoy!

post #3513 of 6832
Quote:
Originally Posted by TrollDragon View Post

Great info on the DAC_1, I was pondering this as an addition to the MKIV keeping case style and so forth. Now I don't know, the DAC_1 or an Audio-gd product...

 

I actually had the two units (MK IV SE + DAC_1) stacked for a year before having to keep the DAC closer to the computer for technical reasons, and the stacked pile looked pretty good in fact (a bit of blue LED overkill though... I've long since kept a piece of tape of those horrific Chinese LEDs).

 

Quote:
Originally Posted by gibosi View Post
 

 

The LD DAC-I or this NFB-15.32....  An interesting choice. With shipping, both of these units are about the same price. However, one is a dedicated DAC and the other is a DAC/amp. It could be argued that with the NFB-15.32, I am buying something I don't need, the amp, and I wonder how much this unit would cost if it didn't have an amp? But on the other hand, this is listed at a "promo" price and it may well be that this unit usually costs more....

 

LD DAC_2 is DAC+Amp, same price, no balanced outputs... I find it often turns out better to just get what you need, let go of the useless freebees, and use the money these extra perks secretly cost to get the best gear you can.

 

DAC_3 is their crazy year-old unit with balanced digital inputs and I2S inputs. Interesting offering if you know what you're doing with digital signals.

 

Again, a regular person with regular gear shouldn't blow over $300 on a DAC imo; at least not without a solid transport or music computer rig before that...

 

Quote:
Originally Posted by wje View Post
 

 

My take on the offering.  Price is $235.00.  Plus, add in about $45.00 / shipping as well as PayPal fees, and you'll have a "close" accurate estimate to the cost.  I see options for the DAC end and the ESS Sabre is listed.  Normally, on their gear, the ESS Sabre is usually more costly and I suspect the Wolfson, would come standard - or, that's my impression.

 

I'm a big fan of Wolfson chips; they do everything well and couple with any gear nicely. The Sabre chips are probably better overall, but some people just can't get used to them for some reason... I'd love to get a ESS Sabre based DAC one of these days just to change flavors once in a while. We all know the implementation of the chip is just as important as the chip itself in DACs though...

 

I'll keep my posts relevant and back to tube rolling from here on... Too much distraction around here...

post #3514 of 6832

The Reflector is a nice tube imho but the EV is better again but neither seems to have a following like the Voskhods. The 'basic '6N23P' Voskhod from the 70s seems to be the goto Russian '88' atm but are getting hard to find now and expensive. Two years ago you could hardly give them away! [not tried these on LD yet only other amps]. Just treated myself to some Siemens CCas :)

post #3515 of 6832

A few days earlier, I had mentioned static being received on one channel of my LDI+ amp.  It was intermittent static.  After cleaning the tube prongs with some emory cloth to clean up the oxidation, the intermittent static went away as mentioned earlier.  However, there was also one other change that I've since noticed.  Both of my tubes now really glow - and, at a consistent level.  Before, it seemed just like was was brighter, and the other a bit dim.  Now, they are both brighter and on par with respect to that brightness being observed on both tubes.

post #3516 of 6832

Gearing up for using 12AX7 tubes in my rig. So far I got one each of Sylvania 12AX7A and 12AT7 tubes. Also got one each of Syl 12AU7A and 12AZ7A tubes. Would appreciate if somebody could tell me if the last two tubes are compatible with the LD MKIII.

 

As regards my receiver, turns out that one channel burnt out. Have to send it back to the manufacturer.

post #3517 of 6832

I just realized that although I have mentioned my pair of Orange Globe Amperex ECC88, I neglected to post a picture. Of course, they have orange print with an orange globe of the world. These particular tubes were manufactured in 1971. They are said to have an "A-Frame" supporting the getter. And instead of a halo getter, these have a round disk getter with dimples. The earlier Amperex BugleBoys, manufactured in 1960, have white print with the BugleBoy logo, and a metal disk supported on two legs below a halo getter.

 

While I have not had a chance to critically compare these tubes, my impression is that they are very similar and both are excellent. Further, the BugleBoys and the Orange Globes can often be found for around $25.00 a pair. If you are thinking of trying some 6DJ8 / ECC88 tubes, I strongly recommend both of these.  

 

 

post #3518 of 6832

I just received two 6DT6A tubes, one of them are  PHILCO Star light (Ford related) and the  other IEC Mullard (International Electronics Corporation.

 

Do the tubes have to be matched pairs or from the same company for them to work properly on the Little Dot 1+?

post #3519 of 6832

Need to buy 9 pin sockets for the "flying" 12AX7 tube. There are many different kinds available. What is better for soldering: a socket with solid tabs , a socket that has holes in the tabs, or a socket saver that comes apart and has pins coming out instead of tabs? Looks like some sockets are one piece, and some two piece. Any advantage of one type over the other?

post #3520 of 6832
Quote:
Originally Posted by Sony Slave View Post
 

I just received two 6DT6A tubes, one of them are  PHILCO Star light (Ford related) and the  other IEC Mullard (International Electronics Corporation.

 

Do the tubes have to be matched pairs or from the same company for them to work properly on the Little Dot 1+?

 

I suspect that you would get a somewhat different sound from each channel.

post #3521 of 6832

Is there something wrong with my Little Dot 1+? Because every single tube that I roll in sounds exactly the same, do you need a quality external DAC to hear the differences. So far I am using music straight from my MP3 player.

 

I'm even starting to wonder if my Little Dot 1+ is on the right setting.

post #3522 of 6832
Quote:
Originally Posted by Sony Slave View Post
 

Is there something wrong with my Little Dot 1+? Because every single tube that I roll in sounds exactly the same, do you need a quality external DAC to hear the differences. So far I am using music straight from my MP3 player.

 

I'm even starting to wonder if my Little Dot 1+ is on the right setting.


I think the extent to which tubes sound different is probably down to the individual.  I don't usually hear very prominent differences either, though I accept that others do.

post #3523 of 6832
Quote:
Originally Posted by Sony Slave View Post
 

Is there something wrong with my Little Dot 1+? Because every single tube that I roll in sounds exactly the same, do you need a quality external DAC to hear the differences. So far I am using music straight from my MP3 player.

 

I'm even starting to wonder if my Little Dot 1+ is on the right setting.

Imo Its mostly subtle differences anyways.

post #3524 of 6832
Quote:
Originally Posted by Sony Slave View Post
 

I just received two 6DT6A tubes, one of them are  PHILCO Star light (Ford related) and the  other IEC Mullard (International Electronics Corporation.

 

Do the tubes have to be matched pairs or from the same company for them to work properly on the Little Dot 1+?

 

I am pretty sure that Mullard did not manufacture 6DT6 tubes and neither did Philco, so these tubes were manufactured elsewhere and simply relabeled. And therefore, in this particular situation, the company name printed on these tubes doesn't really matter. The real question is who manufactured these particular tubes. Do they appear to have the same internal construction? If so, there is a good chance they were manufactured by the same company, and they should work fine as a pair. If not, then they were likely manufactured by different companies, and of course, they are not a good match. So get out your magnifying glass and take a good look at them. :)

post #3525 of 6832

And speaking of subtle differences...  

 

I have had some time to listen to the Mullard and Amperex ECC88 and the Reflector 6N23P. The Mullards are very good tubes, but given that my HE-300s are somewhat dark, they are just too subdued. The Amperex are a little brighter, with more mid range presence, which compliments my headphones well. The Reflectors are even brighter, but a little too bright for my taste. Further, the Amperex have this wonderful sense of flow, liquid and fluid, which I find very enjoyable. The Reflectors don't seem to flow as well....

 

So for now, Amperex remains at the top of the heap.

 

Next up, the Tesla PCC88. As they are NOS/NIB, whereas all my other dual triodes have been used, these need to be burned in....   (>_<)

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