[manaox2]

Quote:

Originally Posted by tomb /img/forum/go_quote.gif As for Beezar parts, I'll be putting up a 0.18uf 96P-series Vitamin Q shortly that pairs very, very well with Nichicon Muse ES's. It makes them sound very close to Black Gates. Motherone on DIYForums.org also has had great experience with the ES's using Xicon MKP's, of all things. So, the ES's can give great performance with the right bypass. They're pretty good with Wima's, too. ES's with those VitQ's in front and Wima's elsewhere, 12FK6's, and 2SC3422/2SA1359's is very hard to beat and not very expensive, either - at least $100 cheaper in parts than using Black Gates. Black Gates are very nice and unbeatable if you have the time for break-in and use them often (they will lose their break-in if you let them sit too long). So, take your pick, I guess.

Thanks for the great summary, I've added it to my notes. I'll be happy to save the $100, capacitor rolling could be a future option. Thats great news about adding the 0.18uf VitaminQ's to Beezar, I remember reading about that discovery earlier too(I'm reading through the thread backwards currently). I'm really happy to be at the front line for the improvements, if only everything in DIY was this well researched as a community.

I'll try to contact Amphead tomorrow to ask about possible impending problems and the balanced implementation. If I get this done properly guys, I'll be happy to provide some notes on the experience.

 

[joneeboi]

I'm wondering if anyone, who bought those used 50VA wallwarts from Beezar, is getting crazy loud humming from the unit. I tried opening it up, but it really isn't cooperating. I wanted to just secure the toroid somehow that is fire-safe, but I couldn't even get it opened. Since I rearranged my room, it sits right next to where I listen to my music, and the sound can be transmitted well across the room (I switched out carpet for fake laminate hard wood). I can hear it everywhere, and now I have to start unplugging it, a hassle. Should I chop it open or buy a new one, find a new one in a dumpster, dip it in a vat of epoxy?

 

[fault151]

has anyone got any pics of the alien dac that they have made? Im thinking about making one. Was it a fairly easy build?

 

[ruZZ.il]

Quote:

Originally Posted by fault151 /img/forum/go_quote.gif has anyone got any pics of the alien dac that they have made? Im thinking about making one. Was it a fairly easy build?

here are some I have floating around:



These are actually a little more than the standard board, with the additional board that helps mounting it securely in a hammond case, and with bypass caps on one too. basically, the build is pretty straight forward if you have steady hands and some tweezers. read through some techniques for smd soldering (tangents site for instance) and you should be ok. I use flood and absorb for the main chip (with solder wick braid).

 

[fault151]

cheers for the pics. How does the dac sound overall? It looks pretty small and compact.

 

[tomb]

Quote:

Originally Posted by joneeboi /img/forum/go_quote.gif I'm wondering if anyone, who bought those used 50VA wallwarts from Beezar, is getting crazy loud humming from the unit. I tried opening it up, but it really isn't cooperating. I wanted to just secure the toroid somehow that is fire-safe, but I couldn't even get it opened. Since I rearranged my room, it sits right next to where I listen to my music, and the sound can be transmitted well across the room (I switched out carpet for fake laminate hard wood). I can hear it everywhere, and now I have to start unplugging it, a hassle. Should I chop it open or buy a new one, find a new one in a dumpster, dip it in a vat of epoxy?

Joneeboi, it's a code violation to even open one. I know that doesn't stop most of us DIY-er's, but you will more or less have to destroy one to open it up.

It's quite possible that yours has gone bad. Since they're used, I plug everyone one of them in to test that they work and that there's not something unusual like you're describing. Nevertheless, they are used and there's a small chance that something like that can happen to them. I've personally used about 5 of them - have one at work with me now - and have never had a problem.

Nevertheless, the supply has dried up. So I started carrying -brand new- versions of these monsters that are fully guaranteed (at a correspondingly higher price, unfortunately).

 

[tomb]

Quote:

Originally Posted by manaox2 /img/forum/go_quote.gif Thanks for the great summary, I've added it to my notes. I'll be happy to save the $100, capacitor rolling could be a future option. Thats great news about adding the 0.18uf VitaminQ's to Beezar, I remember reading about that discovery earlier too(I'm reading through the thread backwards currently). I'm really happy to be at the front line for the improvements, if only everything in DIY was this well researched as a community. I'll try to contact Amphead tomorrow to ask about possible impending problems and the balanced implementation. If I get this done properly guys, I'll be happy to provide some notes on the experience.

Forgot to mention the Russian K42 capacitors. Sound and quality go something like Wima -> K42 -> VitaminQ's. The K42's are not as detailed as the VitQ's, but have more punch. So, they make a good pairing with 12AE6's if you want the basshead treatment.

 

[jarensberg]

Quote:

Originally Posted by tomb /img/forum/go_quote.gif Yes - Joneeboi is probably correct. You'll get up to 40mV or more with the trimmers at dead zero. If you only screwed them down 20 turns instead of 25 turns, then 70mV may still be OK. I'm with Joneeboi - see if you can start adjusting upwards and they change accordingly - go 5-10mV at a time until you get to 90-100mV. Let it sit there for a few hours, checking it every once in awhile and listening to the sound. If all's well, then boost it up to 110mV - you're done! They should be able to take 200mV for short periods. That's on the low side for MOSFETs, for instance, but we normally recommend 1-1/2" sinks in that case. Still, it's not that bad - assuming you don't find something wrong.

Thanks! I'll give it a shot and see how it goes.

 

[Migroo]

Hi guys

Some progress tonight!

I've also added the WIMA caps since taking the photo, but that can wait for another evening. This is a glass-jar audio kit

I'm just waiting for a couple of items to come in and I'm ready to go!

Want to clarify something - I currently use a PSU which my Dad made a few years ago. It outputs DC (and can do 24v). According to Dad, putting DC into the Millet Max should be OK, but I wanted to check with you guys too. From what I can see, the DC will just pass through (half of) the bridge rectifier and into the amp without problem.

 

[tomb]

Quote:

Originally Posted by Migroo /img/forum/go_quote.gif Hi guys Some progress tonight! I've also added the WIMA caps since taking the photo, but that can wait for another evening. This is a glass-jar audio kit I'm just waiting for a couple of items to come in and I'm ready to go! Want to clarify something - I currently use a PSU which my Dad made a few years ago. It outputs DC (and can do 24v). According to Dad, putting DC into the Millet Max should be OK, but I wanted to check with you guys too. From what I can see, the DC will just pass through (half of) the bridge rectifier and into the amp without problem.

Looks good so far!

About the DC supply. What your Dad says is completely true, of course! However, there's the regulator to worry about. Quality, linear regulation is extremely important for the MAX because that supply voltage is carried throughout the rest of the amp with no more regulation - supplying heaters, tubes, and DB's. It has a great deal to do with the quality of sound produced by the MAX.

Unfortunately, the LM317 will need to burn about 3 volts to give you linear regulation. That means you'll be down to 21VDC probably under load. Cut that in half (10.5VDC per tube), and it's not enough to support the minimum voltage needed by the heaters. You need more voltage.

The reason 24VAC is such an advantage is that when rectified and smoothed by the big power caps, the resulting DC voltage is (1.414 x 24) - 1.4 = 32.5VDC. From there, the regulator burns its 3 Volts leaving a maximum of 29.5VDC to supply the MAX. We tune it down from there to 27VDC and burn a bit extra through the regulator heat sink. That's because there are variances in line level voltages from place to place in the US (some are 110VAC, others 120VAC). If the line voltage is not high enough, but you have the MAX board set to that ~29.5 maximum, you may lose that 2-3V burn through the regulator, and the supply may drop out of regulation. Setting it at 27VDC pretty much guarantees the regulator will always have plenty of volts to burn and that the MAX will always be under total linear regulation - ensuring good quality sound.

 

[Migroo]

Hi Tom,

Thanks - an interesting read. I'll have to do some investigating and see how much voltage I can get out of this thing. Its currently happily powering my Pimeta at about 18v.

If I have to find / buy a 24vAC wall wart it isn't the end of the world

 

[ruZZ.il]

I'm not sure the diodes can handle the full load cycle? Anyway, thats not the ideal way of powering it. The MAX could be adapted to work with an external DC supply but I wouldn't just feed it straight through. Inputting 24vdc through 2 diodes, through a regulator, etc will have quiet a voltage drop and a redundant regulator leaving you with less than 24v, far from ideal. You could probably leave out the diodes and regulator and patch the 24vdc straight in but you're still left with 24v. Just build up the PSU on the MAX and use a transformer. you'll get a solid 27~28Vdc and leave it as is, IMHO. unless you really cant find a trafo..

edit: I'm beat, I cant compete, you're fit for the feat and just too damn neat!

(kudos for that)

 

[tomb]

Quote:

Originally Posted by ruZZ.il /img/forum/go_quote.gif edit: I'm beat, I cant compete, you're fit for the feat and just too damn neat! (kudos for that)

You got me beat on the poetry for sure.

Nice to know you had my back, though.

 

[slowpogo]

I'm using a 1 amp Triad wall wart, with my BJT Max. Would there be any audible advantage to using one of the larger Beezar wall warts, or is it just more juice that my amp wouldn't use?

 

[Marzie]

Anyone have any extra superbright blue or violet LEDs for the tube lights? I didn't order them and if anyone has some or a source to get some fast (I will be checking my local place on the weekend) I am all ears!

Mike