Recommend amp project for Vandersteens

[joshzero]

Hello,

I'm tossing around the idea of building a Pass-style amplifier to drive Vandersteen speakers. I currently have the Vandersteen 1c's, but I will upgrade to 2ce's next year and I would like the amplifier to be able to handle both.

This will be my first time building an audio amplifier, but I am not afraid to tackle something a bit difficult. Along with your recommendation please also provide an estimate of the cost for the parts-- doesn't have to be extremely precise, just an order of magnitude.

Thank you,
Josh

 

[carpenter]

Hello Josh,

Since you're a first time amp builder, I'd suggest you begin with a simple, single transistor amplifier to get-your-feet-wet--anything in Nelson's earlier Zen series. Once you've gotten the hang of handling components, you can advance your desire to a larger amplifier. It's like crawling before you walk, walking before you run.

All the best,

John

 

[jupiterjune]

Josh-
Are the Vandersteen's easy to drive? What is the minimum imdpedence and phase angle.

And how loud do you typically like to listen?

These will make a big difference in the recommendations you get.

JJ

 

[Don S]

Hey JJ, good to see you again. Very good questions on your part!

I have owned 2C's and still own 1B's. Both are pretty easy loads to drive. Your best simple calculation would probably be around 6 ohms for both. Tube amps will drive them both full range without a problem. The speaker efficiency is only a DB or 2 different. I have not heard them with little SE's though!

Josh you have opened the Pandora's Box as far as amp choice. Any good amp will make them sing very well. How much power are you driving them with now? Is it loud enough? What amp do you use now? What do you think the areas of weakness are with your present amp?

JJ, I am sure you follow me. What is a good transistor choice? What is the use, what are the circuit conditions? What do you want it to do?

Thanks, DonS

 

[Magura]

please also provide an estimate of the cost for the parts-- doesn't have to be extremely precise, just an order of magnitude.

Thank you,
Josh

The cost of just about any of the Pass amps is starting out at 1000USD and there is practically no upper limit

The reason why most of them cost from 1000USD is that they are mostly in need of the same amount of power supply and heatsinking, and that's the expensive part. In other words, once you got athe box and a reasonable PSU, you can just replace a handfull of parts, and get pretty much any pass amp you'd like.

Magura

 

[hifimaker]

I'm currently using Vandersteen 2ce's and they are an AWESOME speaker.

They have a nominal load of about 6 ohms and 88spl efficiency. I drive them with a single stereo DIY Aleph30 and that's more power than what's needed. Cranking my BOSOZ to 2/3 volume, you can hear the system half way doen the block with the doors and windows closed.

The sound is crystal clear even at high volume.

Used factory built Aleph30's sell for about $800usd on www.audiogon.com.

The 2ce's and 2ce Signatures are a hugh improvement over the 1c's.

-David

 

[joshzero]

Thanks for the help so far. Right now I'm driving them with a Cambridge Audio A1 @ 30Wpc. They sit in a roughly 30'x12' room along the long wall. I listen mostly to pop, jazz, and classical. I usually listen at moderate volume, sometimes at high volume, but never ridiculously loud.

Like the poster said, I'm sure opened Pandora's box. I am just curious to hear about any possible synergistic matches with Vandersteens.

Projects of all difficulty welcome.

Thank you,
Josh

 

[MEGA_amp]

Whats your budget?

 

[joshzero]

Trying for $1k or less.

Thanks,
Josh

 

[MEGA_amp]

You could jump right into an Aleph build, I did. I started procuring parts to build an Aleph 2; 100 watts(300 watts dissipation). This meant large heat-sinks, large chassis, large capacitors, everything about it is big. I decided to change routes and go with the Aleph5, which puts out 60W into 8 ohms and dissipates about 150 watts/ch. This way I was able to put a stereo unit into one chassis versus going monoblock which would have been the case with the Aleph2, and of course saving a few bucks on the way. You have a relatively easy load there, and 60 watts should be more than adequate with room to spare. The only hurdle with these Pass projects is finding a suitable chassis. There aren't many ready made chassis out there that can dissipate this kind of heat, so you'd have to build that yourself. Find very large heatsinks, and build around that. But if your gonna go for the gusto right off the bat, you need to get up to speed.

Some light reading:

http://www.penguinlovers.net/audio/
http://www.users.on.net/~mefinnis/passlabs/index.htm
http://www.facstaff.bucknell.edu/esantane/movies/a40.html

 

[Zen Mod]

Thanks for the help so far. Right now I'm driving them with a Cambridge Audio A1 @ 30Wpc. They sit in a roughly 30'x12' room along the long wall. I listen mostly to pop, jazz, and classical. I usually listen at moderate volume, sometimes at high volume, but never ridiculously loud.

Like the poster said, I'm sure opened Pandora's box. I am just curious to hear about any possible synergistic matches with Vandersteens.

Projects of all difficulty welcome.

Thank you,
Josh

just make Babelfish

you can find parts easily ,even input Jfets ;

you don't need unobtanium 2SJ109 for that, matched pair of adequate singles are good enough

if you are interested,I can dig few links where you can find them easy

 

[Magura]

Trying for $1k or less.

Thanks,
Josh

Hi Josh,

I'm not trying to kill your spirit, so don't get this wrong.

I have made quite a number of pass amps and have been co-pilot on even more of them. If this is your first amp and you have no equipment for metal working you are facing more than $1k to get an amp. Most people get a nasty surprise when making pass amps, as just about any of the big hardware is pretty expensive (and those who didn't get a nasty surprise when they paid for the parts, got a nasty surprise when they ended up with an amp that was lacking in one or more aspects). The most common mistake is to not have enough heatsinking capacity, so the amps run too hot. The second most common problem is too small trafo's, which also isn't too much fun.

Do yourself a favor and take a look at the used Aleph's at audiogon, as this will surely bring you a lot more for $1k than building something yourself. The DIY route is something you take for fun, not cause it's cheaper....cause in most cases it's not.

If you still want to build an amp yourself, the starting point is to build the chassis. The electronics part is mostly not a problem, as remote support from us here at diyaudio usually is good and plenty


Magura

 

[jupiterjune]

If you still want to build an amp yourself, the starting point is to build the chassis. The electronics part is mostly not a problem, as remote support from us here at diyaudio usually is good and plenty

Good advice. I now like to gather the parts first, (at least the PS parts), and figure out how much room they will need. You will also want to allow some clearance room. I possible, allow some extra room around the transformer.
Then build the chasis based on these size requirements.

I just rebuilt a mini-A because I didn't have enough room in the chasis to upgrade the PS. Then I made a 2nd new backplate for it when I went from 250 VA transformer to 400 VA's.

JJ

 

[Magura]

Good advice. I now like to gather the parts first, (at least the PS parts), and figure out how much room they will need. You will also want to allow some clearance room. I possible, allow some extra room around the transformer.
Then build the chasis based on these size requirements.

JJ

Well for a decent Pass amp, all you need to know is how big a 1000VA trafo is, and how much room the 100.000uF caps for the PSU are going to occupy...and don't forget to make room for the inductor

If you wanna make the chassis real versatile, make it a 2*18V trafo and allow space for 4 capacitors in order to make it possible to run both positive and negative rails. Oh, and don't forget to make room for an extra inductor in that case

The rest is not really a problem

Magura

 

[joshzero]

Thanks for all the replies. If I end up doing this project I will be doing it for fun. One of the aspects of this diy project that appeals to me is that after building one chassis if I want to try an amplifier of different design I can build another and change out the electronics. I do have use of a machine shop, so if I need to cut & mill odd shapes of aluminum, or do some drilling & tapping it wouldn't be a problem.

Thanks for all the replies, links and suggestions. I definitely have enough to get started here.

Josh