My DIY SVT bass amp

[bongomania]

Is that one of the new VietnAmpegs?

Lame.

 

[BassyBill]

wow, thats really awesome, i'd love to know how to do that stuff. god just didn't gift me with the electronic knowledge

Er... I think okabass probably studied electronics.

Nice amp, enjoy using it!

 

[tombowlus]

Tombowlus just got on a flight to Finland.

Thinking about it!

Man, that looks great! I love the big transformers and the hour meter is a killer idea! Does it have a reset?

Tom.

 

[Pako]

Awesome build! Would love to hear it. Very, very nice. Only if I had the smarts and resources, it would be great to play a head that was hand built by yourself.

 

[BarryS]

Very nice work. Building an amp is a dream of mine, guess it's time to buy some books and study up. Did you go by just the ampeg schematic, or create your own?

 

[okabass]

Very nice work. Building an amp is a dream of mine, guess it's time to buy some books and study up. Did you go by just the ampeg schematic, or create your own?

HI

The Internet is an endless source. Also,"The Ultimate Tone" book series by Mr. Kevin O'Connor (London Power) is really great.

No, I did not go by just Ampeg schema. My amp has all knowlidge, that I've got thru about 30 years playing and intrest about tubestuff. (this is NOT an advertisment )

Feel free to ask, if you like.

 

[okabass]

Is that one of the new VietnAmpegs?

Hi

Here in Finland we're not very keen of a compraison of the old communist countries. (Russia,Cuba,Vietnam ...) Finland has never been a communist society.
I'd like to say, that we finns put "out of te row " about 2 million Red and then Sovjet army soldiers during the II word war. Our population was then c.3 mil people.
There's three Euoropean capitals, where the enemyes victory parade has never marched: London, Moskow and Helsinki.

Please,I'd like to understand onvards , that Mr. Bush is the only **** in your great state. Thank You.

 

[mike_v_s]

Bush is from Tennessee? I knew I'd been drinking a lot the last few years, but damn.

Mike

 

[bongomania]

Internationally, the word "state" is often used to refer to nations.

 

[mike_v_s]

Internationally, the word "state" is often used to refer to nations.

I know (degree in political science), but I figured I'd try to dilute the political and personal pot shot that was taken.

Mike

 

[vindy500]

okabass was offended, and rightly so. if you put in a whole lota money and time into something and someone asks if it was made in a cheap asian place how would you feel?

 

[mike_v_s]

okabass was offended, and rightly so. if you put in a whole lota money and time into something and someone asks if it was made in a cheap asian place how would you feel?

If I was Vietnamese, I'd feel offended by your comment. If I had the expertise to build said amp, I'd be satisfied with my product and knowledge of it's capabilities and shrug off anything negative anyone had to say....THEN I'd dog out his country's leader and him in the process.

Mike

 

[KingOfAmps]

Hi

Here in Finland we're not very keen of a compraison of the old communist countries. (Russia,Cuba,Vietnam ...) Finland has never been a communist society.
I'd like to say, that we finns put "out of te row " about 2 million Red and then Sovjet army soldiers during the II word war. Our population was then c.3 mil people.
There's three Euoropean capitals, where the enemyes victory parade has never marched: London, Moskow and Helsinki.

Please,I'd like to understand onvards , that Mr. Bush is the only **** in your great state. Thank You.

okabass,

I realize I could have been more clear but I was trying to take a swipe at Ampeg which I now refer to as Vietnampeg. I have a lot of pent up angst over the impending demise of America and have strong feelings towards companies like "Ampeg" which turn their backs on their American roots. Since this is "Amps" I'll start another thread in "Off-Topic" to address that angst.

I apologize to you if it came at your expense.

I would buy your amp before I would buy a Vietnampeg any day and I respect your ability to build an amplifier.

 

[KingOfAmps]

Please,I'd like to understand onvards , that Mr. Bush is the only **** in your great state. Thank You.

I forgot this part.

Please do not take this the wrong way but I have no idea what this means or what you are asking. I'm sure it's just "lost in translation". If it's off topic maybe you can post in in my angst thread over in "Off-Topic".

 

[RWP]

WOW I am really impressed. Being an amp-o-holoc I know how much work that was. That output transformer is killer.
Way to go!!

 

[barroso]

You have my complete admiration!

 

[metron]

Nice work! Possibly the most interesting thing I have ever seen in the amps forum.

 

[BillyB_from_LZ]

Nice work Okabass!

Were there any surprises for you along the way? Any changes that you had to make near the end of the project that you would like to share?

Is there any aspect of your design that you would change if you were to do it again?

I think that we can learn a lot from changes that you had to make for what ever reason.

 

[okabass]

okabass,

I realize I could have been more clear but I was trying to take a swipe at Ampeg which I now refer to as Vietnampeg. I have a lot of pent up angst over the impending demise of America and have strong feelings towards companies like "Ampeg" which turn their backs on their American roots. Since this is "Amps" I'll start another thread in "Off-Topic" to address that angst.

I apologize to you if it came at your expense.

I would buy your amp before I would buy a Vietnampeg any day and I respect your ability to build an amplifier.

HI

Ok. No hard feelings.

Perhaps I too should have think twice, before I write an answere.

 

[okabass]

Nice work Okabass!

Were there any surprises for you along the way? Any changes that you had to make near the end of the project that you would like to share?

Is there any aspect of your design that you would change if you were to do it again?

I think that we can learn a lot from changes that you had to make for what ever reason.

HI

Surprises? Not much. Worst was that the powertrafos primry leads were wrong at the schematic. It began to oscillate, when you raised the bias. It took a while to find out what was wrong. (several hours). That part of the circuit was from TUT 3.
That was also a surprise, how hard is DIY a decent front (face)plate. Perhaps in the future I order factory made front plate. The best positive surprise was how good the amp sounded.

Changes? Some minor changes. Like four rubber feet instead of six. I left the D.I. out. (I use a mic). I needed more gain, so I changed one 12DW7 to 12AX7 and put a bigger anode resistor. I first used 7ender grille cloth for front baffle, but then I found something, that resembles Ampeg cloth.

What would I change now? Not much either. If I'll found good rocker switches for "ultra hi", "dirty" an "ultra lo", I'll change them. And a factory made front or face plate maybe. Perhaps I'll put XLR or speakon speaker outputs.

I'd like to say that keep circuit simple. Take everything out that you don't need. That big tube amp has so good sound by itself, that you don't need any complex tone shaping (graph eq). The basic SVT-pre controls are all you need; That's my opinion. I even thought to put there an eq bypass switch. Use good parts. Make good solder joints: that's important.

And last but not least: Make sure that the circuit is ok _before_ connecting power. The amp has so high voltage and current capability, that a major disaster is otherwise at the door. I connected one 2k/5W ceramic wire wound resistor wrong. It didn't burn and smoke: it literally exploded away. I found only a few, small fragments of it. Luckily I wear an eye protection.