[2359glenn]

Those apps are great.
I am just saying that the SQ of cell phones are horrible. Was just talking to my new boss and he sounded like he was under water.
Had a analog cell phone and it sounded pretty good. And drove through 4 states with my lady on the phone and it never dropped the call.
They should try working on the actual phone part and make it work right. It does everything else GPS internet good just the phone
part sucks.

 

[Zachik]

They should try working on the actual phone part and make it work right. It does everything else GPS internet good just the phone
part sucks.

Glenn - most people (especially younger generation) do not use their phone to make any phone calls anymore...
For them, it is a digital communicator by means of text, e-mail, Instagram, etc.

 

[Tjj226 Angel]

Glenn - most people (especially younger generation) do not use their phone to make any phone calls anymore...
For them, it is a digital communicator by means of text, e-mail, Instagram, etc.

Nah. Im sort of in their weird middle ground in terms of age, but I do sadly count as a millennial.

Most younger kids, people around my age, and older adults I know still make calls over texting. It just depends on the situation. For instance if I am meeting someone for a job somewhere, they might text me to let me know they are 10 minutes out. However if they get a flat tire along the way and they need help, they will call.

I would say that texting is the new form of sticky notes more than the new form of calling someone.

 

[L0rdGwyn]

I have been quietly enjoying the spoils of my work, but that does not mean DIY shenanigans have ceased...I have three projects in the works.

1) Plans are taking shape on my 841/801A A2 build, to the point that I am ordering parts for a prototype. LTSpice can only go so far - all is well and good in the models, time to test in the real world. It will be something of a drawn out process, different than my approach in the previous two amps, but it will be necessary to work out the kinks as the design is more complex. Very much looking forward to getting these tubes in an amplifier, they will double as a night light.



2) Still waiting for my Omega speakers - I suspect a delay as Louis told me he moved into a new workshop - no rush on my part. Once they are in my stereo, I will be doing surgery on the Snells to re-cap, re-resistor, and re-ferrofluid. Want to do it all in one go, just need some speakers to listen to while I tear them apart.

3) And lastly, the 6A5 revamp - R120 tubes are on the way. When I have them, I will be making some changes to the power supply in addition to adding voltage regulators on the driver tube heaters. All the power supply parts are on hand and the regulators are assembled. If the changes are positive, I will be moving the amp into a new chassis with improved ventilation and layout for the additional regulator boards, correcting some oversights from my first build with more knowledge and experience under my belt.

So that's my non-update update. I'll post again once I have something I am physically working on.

 

[chrisdrop]

they will double as a night light.

Perhaps as a spin-off; "vintage artisanal lighting". I am sure there is a market. The "quality of the light spectrum cast" is the new "quality of the tube sound".... Custom lampshades... LOL

 

[L0rdGwyn]

Perhaps as a spin-off; "vintage artisanal lighting". I am sure there is a market. The "quality of the light spectrum cast" is the new "quality of the tube sound".... Custom lampshades... LOL

People on Etsy would eat it up! As long as they can find use for a 9W light bulb lol. That was my girlfriend's reaction...

Me: "Look at the beautiful filament glow from these rare vintage tubes! Aren't they pretty?"
Her: "They look like light bulbs."

-_-

 

[johnjen]

Me: well they are and so much more. It's a good thing too because now I can listen to music and light up the night all at the same time!!!

JJ hahahahahahahaha

 

[L0rdGwyn]

Starting to make some real moves on this next amp. All of the parts for the prototype are ordered (I think...hard to keep track). Have a massive shipment coming from Mouser tomorrow. Usually the little passive components represent a somewhat negligible expense compared to the other parts - not the case this time around. Lots of sand assistance in this build, so lots passive components.

For the prototype, I got these cool socket boards from Hificollective.



And everything will be built on the 2'x2' piece of plywood below, doing both channels.



This amp will have four different power supplies, Antek transformers, although I haven't ruled out switching to something else for the big guy in the middle for space saving measures since I am only using one of the two secondary windings. The 841 B+ (via voltage doubler), 801A B+, and source follower V+ will be Maida regulated; the source follower V- / bias supply will be shunt regulated.

Rod Coleman regulators for both input and output tubes, filament bias for the 841, fixed bias for the 801A. I was originally looking at getting some cool meters for the 801A fixed bias, but I am starting to consider using test points and current sense resistors instead for a few different reasons, one of them being space. That is TBD, but will be the approach for the prototype.

The circuit I am using for the 801A bias as well as the constant current sink for the source follower will need to be prototyped - I have some solderable prototyping PCBs coming to build them out. Once everything is up and running, I will put together the gerber files and order the finalized PCBs.

Yet another thing coming to me - a giant 12" x 7" x 3" heat sink. Has something like a 0.25 C/W thermal resistance with zero airflow, going to throw all of the regulators on that bad boy for the prototype, will use it for future prototyping as well.

By the time I get this all laid out and the power supply and input stages working appropriately, the output transformers should be here.

So yeah, this is the big project right now, a monster of a 801A A2 SET amplifier, ~6-7W output into 8ohms.

 

[L0rdGwyn]

Some more bits and pieces going into this amplifier.

Here is one of the completed Maida regulators - well sort of, the reg and FET chips are not actually soldered on yet, that will be done when attached to heat sinks. This particular variation of the Maida is the work of @A2029 , so mad props to him, vastly simplifies the power supply, and it still isn't very simple. This baby eats ripple for breakast and has very low output impedance across the audio band. They will be used on the 841, source follower, and 801A supplies.



Here are the Hammond filament transformers for the input and output tubes. Yup, one per tube, feeding the Rod Coleman regulators. Again, a monster.



Panel mount fuse holders and fuse, protecting the 801A from thermal runaway in the event of a bias supply failure. This is the most expensive fuse I have ever bought, but it met my spec...not even made of gold and audiophile crystals...these will go on the amplifier chassis back panel, beneath the output transformers.



Prototyping board - my source follower circuit, constant current sink, and bias circuitry will live on these before proper PCBs are made.



And the oh-so-important power switch. I sort of have a thing for toggle switches, decided to go for it this time around. This particular one is pretty and has very satisfying tactile feedback. It is also waterproof, so if my living room floods and my amp is submerged, at least my switch will be spared.



More stuff on the way believe it or not. I didn't intend it this way, but probably the best thing about this build is that it will keep me busy for quite a while. I need to be working on something to distract me from...stuff, so I welcome the complexity this time around.

 

[Xcalibur255]

NKK switches are awesome.

 

[L0rdGwyn]

NKK switches are awesome.

Loving it so far. Need to stop switching it back and forth, I'll wear it out before it even makes it in an amp

 

[johnjen]

I like using big honk'n toggle switches with their satisfying Ca-Lick, so I go for the 2 pole 20 amp rated ones with the larger baton.
A Manly Mans switch… hahahahahahahahaha

JJ

 

[Zachik]

NKK switches are awesome.

I agree!
I have built a (my first audio DIY) switch box for connecting 2 amps to 1 set of speakers, and used NKK switch. VERY satisfying switch to use!!

 

[L0rdGwyn]

Results from an evening of board stuffing: three Maida regulators, dual channel bias shunt regulator, four raw DC boards for Coleman regulators, and the four Coleman regulators.

#Regulated



Working this weekend, so I will start laying out the prototype early next week. By then my giant heat sink will be here and the real fun will begin

 

[L0rdGwyn]

YES.



To be continued.