Hello, my name is Mark Schneider. I started Linear Tube Audio, LTA, 4 years ago. Here is my story.
I had met David Berning through a friend, who had him make some custom amps for some homegrown electrostatic speakers. I had retired from my engineering director life and had spent a couple years reading the paper, then learning some board layout software, and then re-animating a Eico HF-81 integrated amp design from a schematic on the internet. I guess back in the 60s, there were no metal film resistors and they used an excess of ceramic disc caps. Using modern parts, this amplifier came to life and sounded better than anything I had hooked to my Magnepans previously. I was drawn like a moth to the flame to making tube amplifiers.
So, I took may little amp to David Berning’s house, not really understanding that he was one of the leading tube amplifier designers in the world. I told him that I was thinking about starting a company making this tube amp, because it provided such high quality sonics for a few hundred dollars worth of parts. He laughed and looked closely at my amp design. He made some slight corrections, and asked what was the maximum input voltage. I said 2 volts and he said, lets try 5..then he proceeded to put several combinations of resistors and capacitors across the output to make the amplifier oscillate. He adjusted the feedback so that it would never oscillate. I went home and made the mods and came back. I asked if he wanted to be a partner in my little hobby company I was going to make. He laughed again and declined, but said he would license me some designs. I said I wanted to make some products that would provide high end audio sound at reasonable prices. Davids’ least expensive amp at the time was over $8K. So, he mentioned he had been playing with a low cost 10 watt amp design and he had this product he used to make, the microZOTL, a headphone amplifier.
So, I don’t much now, but I knew far less then. I said ok, let me license your designs if you teach me how to make them. He suggested the microZOTL should be my first product, not my Eico knockoff amp, and he had a pile of letters from people begging him to make them a microZOTL. He was using Chinese tubes, the switching supply was in the box and you could hear the hum, and he mentioned that people had asked for more inputs and one guy used it as a preamp. So, I thought I would move the supply to an external supply, get some much nicer Russian tubes, lose the battery input, and put it in a better case.
My background was 20 years in a complex manufacturing environment, and I knew how to breakdown complex processes into smaller subassemblies, using detailed instructions and sub assembly testing. So, I gave him a pile of cash, and proceeded to spend a year and a half learning the microZOTL, making manufacturing instructions (taking a lot of phone pictures of David’s fingers winding things)…getting my friend to make a sheet metal case, and making 50 units myself. I made a website and put the microZOTL on the site. I shipped a unit to one of the people who sent a letter to David. The amp arrived with half the screws undone and the tubes reduced to a pile of broken glass.
I went back to David and he told me about where he got the foam rubber factory to custom cut 3 inch foam scraps into amplifier packing material. I received my order a few days later and shipped a new amp to the guy who had sent the letter. He had one of David’s original microZOTL headphone amps. He compared the new one to the old one. It turns out he is the highly respected guy on Headfi. He writes this two page review raving about the sonics of the new microZOTL and starts a thread on Headfi. The next week we get 5 orders, the week after 10….and we were off.
So, after learning about thicker cases, front panels, external power connection schemes, NOS tubes, long lead parts, linear power supplies, whether looks matter, dealers vs direct, etc., we continued to improve the product in many, many ways. We sold a bunch, and decided to try a couple more products. Working closely with David we came out with the ZOTL10 and the ZOTL40 power amps. Making the first 5 ZOTL40s and taking a month to do so, and then having only 2 work, I really understood how complex and difficult David’s designs were. Then he tells me we were the 3rd company to attempt to make his ZOTL amplifiers. The first two failed and gave up…thanks, David….
So, now it is 5 years later. I have 5 employees, most have been with me building the amps for more than 3 years. We are very comfortable making David’s designs. We have worked everyday to understand how we can enhance his unique approach to operating the tubes that creates the magical realism and reproduction of the original performance.
We have partnered with Fern & Roby to design some cool cases and have paired David’s designs with the best components and parts, to bring out as much performance as possible, and tried to provide the features and configurations that we are asked for. Our newer products are more expensive, but are chock full of the best components that we can find… as long as they provide true product improvement.
We have developed our own control system of remote stepped attenuators, displays, input control, etc. to wrap around David’s amplifiers. We want to provide even more connectivity in the future.
David’s stuff all requires much more labor than other designs, as many components are unique and not available to buy, and must be hand-made. We do not mark up our products as much as many others, as we are still very committed to providing components that punch well above their weight. We get much satisfaction from the happiness that our customers express…and we sell direct, so we don’t have to raise our prices to accommodate dealer margin.
Our biggest issues are that few people know of us, and it seems in audio, if its less expensive, people tend to not believe it can be better than something much more expensive. We are hoping that getting more involved in a forum such as Audio Circle will give more visibility to our products. I am happy to answer any questions about anything. We are looking forward to engaging in this community of positive audiophiles and discussing technology topics and hopefully becoming a site sponsor. Thanks very much for reading this.