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Simple SE with KT88's

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pchw said:



Thanks for pointing that out. I had been looking on ebay but didn't know exactly what I was looking at. I am still waiting for Gery's reponse to email first. I hava feeling I can get my OPT's from him with UL taps for about the same price. If so I would rather go with his stuff. But I'll wait for the email to come back before I decide...


chrish said:
Regarding the FREDs, they have caused problems for me. This happened at the same time I had problems with the standby switch. I suspect a voltage spike from turning the standby switch on fried my FREDs, which then in turn fried my GZ34 rectifier valve (tube). Have gone through two sets of FREDs. Removing them and the standby switch and using a new rectifier valve (now a Sovtek 5AR4 and occasionally a 5U4GB) has resulted in zero problems.

As for output transformers, I think there has been much discussion.

Cheers,

Chris


At this point I am 100% sure I am not going to run the FREDS or a Bypass switch. But will buy the FREDS just incase a tube goes..


jimazz said:
i have the bigger transcendars with ultralinear tap (5K/15w/50% ul tap) with taps for both 8 and 4 ohms, you can email gery and ask him

i paid for mine something like 150 - 160 $ about 2 months ago


i use also the hammond 374bx and the hammond 193J choke and the cap from ebay, alps blue beauty 100k and everything else is exactly as George's parts list



This sounds awesome!!

This is the exact setup I have on paper and plan on buying. Except I was going to use and alps 50k blue pot. Should I get a 100k? The tubelab receommends a 50k best to my knowledge...



Sonicraft got back to me via email. They need the schematic. So I will send them the schematic and wait for a price before I decide on the parts for the board...


I'm getting closer and closer everyday.:D





Nick
 
nikolas812 said:



Sonicraft got back to me via email. They need the schematic. So I will send them the schematic and wait for a price before I decide on the parts for the board...



As others have observed, you pretty much can't go wrong with the Mouse or Digikey parts in George's BOM when it comes to the parts you'll solder to the board. The one exception, perhaps, being the Mallory 0.22uf coupling caps. They're not bad, but since you've expressed a desire to include quality parts, this is a place to spend a (very) few more bucks - Auricap or similar. The Russian PIO caps on Ebay are also a good substitute.

BTW, that soldering station looks like an great deal. It looks like a knockoff of a Hakko station.
 
Alrighty then..

All parts order except for the 2 caps and Power trannies. And misc stuff. RCA,s IEC connec, exc......... But this should be enough to get me going for a little while..

I'll order some Sonicaps in a bit. I have used them in the past and had good results with them..




Nick
 
Whats the typical price to build one of these?



I have bought everything but the Power supply and the price is up there.:eek:


I might have to go for the cheaper power supply Ty recommended and hide the ugly choke in the Chassis...




Can someone recommend some wire types and sizes. This is the only other thing I haven't bought and have no idea where to start..




Nick
 
nikolas812 said:
Whats the typical price to build one of these?



I have bought everything but the Power supply and the price is up there.:eek:


I might have to go for the cheaper power supply Ty recommended and hide the ugly choke in the Chassis...




Can someone recommend some wire types and sizes. This is the only other thing I haven't bought and have no idea where to start..




Nick





Solid core 22 AWG for the small tube heaters and solid 20 AWG for the octal tube heaters. Twist tightly (using a cordless drill and a vise, or your friend, and make about 4'-6' at a time). You want to tuck the heater wires into the edges/corners of the chassis and only venture out to the tube sockets where req'd. Keep the twist tight as close to the socket as possible. For signal wire, you can use CAT5 cable, and for the HV wires, use 600V rated 20/22 AWG or so. You can also use shielded coax for signal wire. Also try to keep the signal wire as far away from the heater wires as possible, to minimize hum.
 
nikolas812 said:
Whats the typical price to build one of these?

Can someone recommend some wire types and sizes. This is the only other thing I haven't bought and have no idea where to start..

I spent about $370 on transformers, circuit board, sockets, and parts. That price does include shipping, but doesn't include chassis materials or vacuum tubes. I used whatever I could find laying around the basement for the chassis, and I'm still not done buying vacuum tubes.

I used some silver plated, teflon insulated, stranded wire I bought off eBay. Honestly, for this amp you're going to need all of about eight inches of wire. Everything is on one circuit board and the transformers come with their own leads. At least they should. :) Just about the only wire you might need is between the RCA input jacks and the circuit board, and maybe a short piece between the fuse holder and the power switch. If you use cathode feedback, you might need some wire there too.

I don't like the shielded wire for the inputs - just mount the jacks close to the right spot on the board, and keep the leads short. Mine aren't more than 1/2" away. Use something about 22 AWG or so. You can put whatever you want between the fuse and power switch. Use an old piece of lamp cord if you like.
 
1. The CEO, President, Senior VP and janitor of tubelab.com (just kidding, it's a one man company) are in Orlando for the weekend selling part of his collection of tubes at a ham fest. He's pretty good about shipping quickly, but I suspect he's away from email for a moment.

As noted I have been out of town since Friday morning. I took about 10,000 tubes that I couldn't use to a tube dealer in Orlando, then went to the ham fest and bought some that I could use, only about 100 though. No internet in the $44 hotel room, but the "ladies of the evening" and the Orlando police provided plenty of entertainment.

For those who don't know a hamfest is a large gathering of of electronics enthusiasts (about 10000 in this case). The primary theme is ham radio and there is an area devoted to sales of brand new radio equipment. There is also a large (OK huge) swap meet for just about anything loosely related to electronics, including vacuum tubes. They are usually anual events. Hamfests have been dying over the past 10 years. There used to be 3 within 20 miles of my house, now the closest is 200 miles away.

Your forgetting the accountant (his wife). It's really a 2 person company

Yes, Sherri usually handles email, and shipping, but she has been here for exactly 4 days this year. Her mother has (likely terminal) cancer and lives alone 1200 miles away. Sherri has been staying with her and taking her to daily chemo treatments.

Whats the typical price to build one of these?

I built one for under $300, but that was a few years ago, everything has gone up in price since then including electronics parts, but transformers have been hit harder than most. I got photos from a customer who spent over $1000 on his, but it looks like a lot of money went into the woodwork.

As others have observed, you pretty much can't go wrong with the Mouse or Digikey parts in George's BOM when it comes to the parts you'll solder to the board. The one exception, perhaps, being the Mallory 0.22uf coupling caps.

I have built a few of these, and that's what I do. Everything is Digikey or Mouser except for the coupling caps. I use Auricaps or another good quality audio cap for the coupling cap. The single biggest influence on the sound quality in a tube amp is the output transformers, next the output tubes, then the coupling caps.

This is the exact setup I have on paper and plan on buying. Except I was going to use and alps 50k blue pot. Should I get a 100k? The tubelab receommends a 50k best to my knowledge...

The Simple SE will work with a 100K pot, but the Tubelab SE doesn't, so I use 50K pots for both amps. If I had an equal opportunity to get both values for the same price, I would still prefer the 50K pot since a 100K pot could theoretically become a limiting factor in "high frequency extension" if a really good output transformer was used.

I might have to go for the cheaper power supply Ty recommended and hide the ugly choke in the Chassis...

Works for me. Some claim that the 374BX is a better transformer, and I am sure it is. It costs twice as much as the Allied, is it twice as good? I don't know, the cheapskate in me has never let me buy one.

Can someone recommend some wire types and sizes. This is the only other thing I haven't bought and have no idea where to start..

On most builds the transformer wires can be connected directly to the PC board terminals. This takes care of the high voltage, and heavy current stuff. There is some primary side (connected to the power line) wiring like the fuse holder and power switch, these should be wired with anything capable of handling the voltage (120 volt AC) and current (5 amps). I would make sure that the wire you use is clearly marked 300 volts or higher and at least #20 AWG in size (don't use cat 5 wire here). Radio Shack has small spools.

There are many opinions on the signal wiring. Shielded cable works well, but is hard to deal with, twisted pair is almost as good. I usually use two strands of wire removed from multi conductor cable (like an old printer cable) lightly twisted. Cat 5 computer cable is recommended by some users.
 
It looks like everything is coming together!

The PC board should be on the way Tuesday.

Gery from transcendar just sent me an email. So it looks I could have my OPT's in a couple weeks.


Thats really it. Now I am just waiting for the parts to start flowing in..



One more question. Do I really need three mulit meters? I have one good fluke and thats all. And I really don't want to spend anymore money unless I absolutely have too...


Thanks for the reply George!

Can't wait to get started..


Nick
 
Do I really need three mulit meters?

I recommend 3 or meters when doing the initial setup on a Tubelab SE amplifier since the user has to adjust bias on a live circuit board. Multiple meters removes the risk of probing and adjusting the board at the same time. The meters are cheap compared to building the Tubelab SE.

The Simple SE is a build it and it plays amplifier. No meter is required unless something is wrong.

I have one good fluke and thats all.

I have a Fluke but I generally don't use it on tube amps. The $4 meters from Harbor Freight are accurate enough, and you don't cry when you blow one up. Yes, I have blown two up over the past 5 years, both the result of being careless.
 
Well. Wouldn't you know it..... I was worried about not getting my board and guess what arrived just about before everything else...

The board!!

Thanks George!!

I actually expected the resistors and stuff from Digi Key to arrive today. And I planned to start on the board.

Hopefully tomorrow the rest of the stuff will show up and I can get started.


After a little persistence I got a hold of Gery at Transcendar and he said my OPT's will be shipping out Monday.

So.. The OPT's will be the last thing to arrive. And I am hoping to have the board done by the time it gets here. And most of my chassis work..



I hope you guys don't mind pics. There probably be a bunch. I like to take them and I like to show them..

Heres a couple of the room and the newly arrived parts.

I had a dedicated room cleared for the build. But I didn't have Internet in there and I wanted to be close to the computer so I can reference the build from the Tubelab website. So I moved the table to my bedroom and setup a little 2 channel rig to listen too while building the amp..:D

Cheers

Nick

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good news, I allready missed the fun of building ......

and keep pics coming ...


btw , is that the dared mp-5?

i had it for some months last year , very beautiful and

quite good, but the simple se is much much better

in fact last week I heard both of them at a friends house along with a trends and a china pp ... that simple se was the clear champion ....:D
 
I've got about 90% of my parts now. Enough to start on my board and chassis.

I drilled some holes and mounted my bottom plate to my chassis and added some rubber feet..


A little bit after I did that my parts from Digi Key arrived and my tubes from the tubestore arrived.


Which was awesome because the Tubestore made and error and sent me the wrong tubes. They sent me Winged C's instead of the Sovteks I ordered. The winged C's are what I wanted in the first place but I didn't want to spend the money. The winged C's cost almost twice as much as the Sovteks. Needless to say I was VERY happy!


I stuggled at first with soldering. But after a few resistors were installed I started to fall into a groove. I still stuggled here and there. But for the most part I think they turned out OK.

If anybody sees anything wrong please point it out to me...

I took 21 pics of the progress today. But I'll limit this post to 8.:D


I also didn't install the FREDS or the Heatsink Diodes. I didn't install the Heatsink and diodes because there wasn't a screw and nut with my parts. So I'll have to go to the hardware store tomorrow before I can install them..


It took me about 3.5 hours to complete the board....


Cheers





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Nice looking amp. Do yourself a favor, and get a pile of Q-tips and some isopropyl alcohol. Zippo or Ronsonol lighter fluid works even better, but is more dangerous. Clean up all the leftover soldering flux (brown junk) around the solder joints before you turn on the amp for the first time.

After it heats up from the first use, you'll never get the stuff off.
 
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