DIY do it yourself tube amp kit

What kind of speakers are you driving? That's the most important factor.

Decware, Bottlehead, and Welborne are best suited for speakers above 94dB efficiency with fairly stable impedences above 8 ohms.

I have Welborne DRD 300B monoblocks and they are stunningly transparent and revealing. The most "pure" 300B amps have ever heard. But, 7 watts per channel will only get you so far.

I have driven 90dB/4ohm Jean Marie Reynaud monitors with them and the combination was great for acoustic, jazz trios, and chamber music. But, larger scale, more demanding works would run out of gas.

Be sure to add Diy HiFi Supply's kits to your list. They have fanatastic low power amps and a 40W PP amp.

Hi Keithmundy,

Sorry to bring this up, but only two of the kits mentioned so far will do your Vandy 5's the least bit of justice - the Velleman K4040 at 90wpc and the Transcendant BEAST at 165 wpc. In fact, the Welborne, Audio Note, other Transcendants, Decware, and Bottlehead amps should never even be considered.

My brother has Vandy 3A Sigs and they are a demanding impedence match. Even though the 5's have a built in 400 watt subwoofer amp, the 3 other drivers are still rated at 87dB w/ an impedence that fluctuates to 4 ohms.

You really want to look for an amplifier in the 75+ wpc range with a stiff power supply to do these speakers any justice. If it was me, I'd go 100+ wpc and there simply aren't many kits in that range.

Hell, the 5's have been known to cause the Audio Research 100.2 to run out of gas on large orchestral works. And that is a serious high-current solid state amp. My brother uses it to run his 3A Sigs.

Keithmundy,

Response Audio does extensive mods on the ASL Hurricanes, though it doubles the price.

If you can get by w/ 100wpc, they also do the same mods on the Monsoons.

Check out the listed changes they make to their amps for ideas.

Are OTL's good with low impedence electrostats?

At the crossover region of 125Hz, I think those speakers were known to drop down into the 2-3 ohm range. Not an easy load, at all.