New Website!

Hi!

After the completion of the Compactron, Heritage and Intrepid product series, they got their own new website. 

In time for the first public presentation of the new gear at the upcoming High End in Munich. See you there!

Best regards

Thomas

The VinylSavor Product Site is Online!

Hi!

I am very proud to announce the launch of my product web site on www.vinylsavor.com

Over the years this blog accumulated more than 600 posts and it got too confusing for people to get an idea about the amplifiers and pre amplifiers I am making. So it was time to launch a separate website to browse through the product categories and get an overview about my offering.

The site initially offers english and german as languages which can be selected on the top left. More languages will be added later on.

The products are organised in categories to make it easy to find what you are looking for. This blog will remain in place to give insight into what is going on and to show new developments and builds, announce news about ELROG tubes and to report about events.

Have fun browsing through my new website and don't hesitate to email me if you have questions, remarks or suggestions.

Best regards

Thomas

Cool Links : www.scheu-analog.de

Hi!

I am often asked about the analogue front end I am using. After the European Triode Festival (ETF) I stayed for another day in Berlin and visited the manufacturer of my turntables: Scheu Analog

The picture above shows the main page of their web site : scheu-analog.de This gives a nice overview of all their products.

In October I had the pleasure to meet Ulla Scheu at the Cool Gales Bath Audio Fest where we demoed our equipment together. Ulla continued to run the business after the tragic death of her husband Thomas Scheu who founded the company. She maintained the legacy of her husband and further established the brand which is well known throughout the world in the audio community. I met a warm hearted woman in Ulla who is passionate about her products. During the event in Bath we agreed to meet up again soon. So I took the opportunity while I was in Berlin and visited her company.


Upon entering the workshop I saw many objects of beauty either in the assembly or testing stage or in preparation for shipment. Here a Cello Classic, the entry level turntable:

A Scheu Diamond with a base made from slate,being prepared for shipment:

The storage room has rows and rows of shelves with parts waiting to be used for one of Ulla's music making machines:

Of course there are also shelves full of records in the listening room:

In the listening room there is a picture showing Ulla with the musician Katie Melua:

Katie is using a Scheu turntable. She has good taste!

One of the work desks at which motor units are assembled:

Note the cloth gloves which are always in reach to handle the motor units with shiny chrome finish.

I got my first Scheu turntable almost 15 years ago when the brand was only known to insiders and the turntables were sold as kits. That turntable has been continuously in use since then. I took to several events for demos and moved it around a lot. It is still playing robustly and sounds like when it was new. That's what I admire about the Scheu products, their robustness and longevity. This holds true as well for the second turntable which I got about 8 or 9 years ago, the Premier Mk2. In the meantime The product line is considerable enhanced and not only contains several lines of turntables but also three tonearms and a range of cartridges which are made for Scheu by Benz Micro.
Ulla brought an awesome pink coloured Diamond to the event in Bath, which I couldn't get off my mind since then. So I had to get one and while I stayed in Berlin we discussed the details of my pink Diamond. While I visited a friend in Berlin, I had the chance to listen to some Shellac recordings which caught my interest (this will be covered in another story). So my new turntable will have to have two tonearm bases one for a tonearm equipped with a stereo cartridge and the other for a mono cartridge for shellacs. Ulla also committed to make a custom motor unit which will allow 78rpm which is needed for shellac playback besides the usual 45 and 33 1/3.

Some photos of a pink Diamond:

The base with the platter taken off:

The bearing:

I can't wait to get my third Scheu turntable which will be used in my workshop.

It has been a great experience to finally visit the creator of my turntables. Thanks a lot to Ulla for the hospitality and for showing her company.

Best regards

Thomas

Cool Links : www.tubebooks.org

Hi!

Today I'd like to share another valuable internet resource for technical information about vacuum tubes and circuits: Pete Millett's tube book page.

Pete provides a huge archive of books for download. In the category Technical Books (link in the bottom part of the front page) contains a selection of various books about vacuum tube circuit theirs. Among those the famous Radiotron Designer's Handbook both in Edition 3 and the huge Edition 4! And there is a separate page for the entire RCA HB-3 Tube Data Manual! Nowadays life is so easy for anybody who wants to get into vacuum tubes. Vast amounts of information are available for free and can be downloaded in a few moments. When I started to get into vacuum tubes in the early 1990ies it took a lot of patience to hunt for those valuable books and they where quite costly too.

I had the pleasure to meet Pete personally at the ETF. He is a great guy and a brilliant and passionate audio designer who is freely sharing a lot of information.

Thanks a lot to Pete for compiling this enormous amount of precious information!

Best regards

Thomas

Cool Links: www.tubedata.info

Hi!

Today I'd like to present a link which I use a lot. Frank's Electron Tube Pages.

Frank Philipse compiled a huge archive of tube datasheets. An extremely valuable resource for any tube enthusiast. With this archive Frank contributed significantly to the conservation and distribution of information about vacuum tubes.

Pretty much every tube data available within reach of a few mouse clicks. A resource which I use a lot. It is so much faster than pulling a tube manual from the shelf and searching the data.

Thanks a lot to Frank for the great work he has done!

Best regards

Thomas

Cool Links: www.tribute-audio.nl

Hi!

Tribute is well known among tube amplifier builders for their high quality transformers. So it is about time that this company get's it's spot in the cool links section.

The company which is based in the Netherlands, is run by Pieter Treurniet. I met Pieter several times at the European Triode Festival to which he contributed with very interesting lectures and also with transformers for shootouts. Pieter is very passionate about transformer development and among the few people on the planet with profound theoretical knowledge and practical experience about transformer winding. He has no standard range of transformers. Each transformer is wound on order which means each one can be customized. This offers a flexibility which is missing from other transformer suppliers or can only be had at a large cost adder or if you order a certain quantity. Not so at tribute! You specify what you want and you will get it.

My preamps all use inductive volume controls driven by step down line output transformers. I always wanted an integrated solution, a step down transformer which can handle DC for single ended operation, with the secondary implemented as a 24 tap volume control. Since this is not available from other suppliers, at least not in the form which I would like to have it, I approached Pieter and asked if he could do such a transformer. Pieter agreed to calculate such a beast and wind them.

This is the result:

A pair of beautifully built single ended line output transformers with volume control secondaries. Primary and core air gap are sized to fit a 10Y or 801A tube. Pieter did first measurements and recommends to experiment with loading resistors between each tap. He found that the transformer operates without any ringing and excellent frequency response like this. Very promising!

Chassis material for the 10Y preamp with these transformers is already being made. I will present the making of that preamp in an upcoming article.

Best regards

Thomas

Cool Links: www.kilimanjaro-series.com

Hi!

During the recent years vintage field coil speakers gained an increasing popularity. Those who have heard a good speaker based on field coil drivers know why. This principle is far better sounding than the more common speaker drivers with magnets. More resolution, more sense of beeing there, more tone, more of everything.

If you are interested in field coil speakers, but don't want to hunt those vintage drivers, of which you can never be certain how good they are after decades of use or storage somewhere in a barn, there are few choices of currently manufactured drivers. One of them is the Kilimanjaro Series by Wolf von Langa. I already used a field coil horn driver from Wolf in a speaker installation and it sounded much better than the TAD 4001 it replaced. I also had the chance to briefly test his field coil version of the Altec 515 woofers. I'm currently in the planning stage of a new speaker set up which will use Kilimanjaro drivers. This is the A2000 horn driver for this project:

For the bass and lower mids I will use the A416 and A515. Below two fotos of one of the woofers:

As much as I like vintage tubes, I feel a bit uneasy to spend a lot of cash for 50, 60 years old or even older drivers. How well are the voice coils still aligned? Have they been abused? What is the condition of the membranes? They sure have soaked up humidity over the decades and are far from their original condition.

The Wolf von Langa drivers are all brand new. No need to worry about aging for decades! For a short while I was tempted to go for chinese copies of a famous WE driver. I'm glad that I did not have to settle for copies but rather got some original work. Precision machined and engineered with brain, heart and soul! And the most important of all: With ears! I know Wolf since a few years and am glad that I can say that we became good friends. He has an exquisite taste, not only in sound and music. The photo on the right shows the creator of these drivers. Thanks a lot Wolf, for pushing the envelope in speaker design. Keep up the good work!

Best regards

Thomas

P.S.: I will write about the progress of my new field coil based speakers in an upcoming series of articles. Stay tuned.

Cool Links: www.intactaudio.com

Hi!

I haven't presented a cool link in a while. After I received a delivery of swedish iron a few weeks ago, I got some US made transformers this week. From Dave Slagle's intactaudio. So it is about time that I write about his website.

I know Dave from the early days of Sound Practices. We both participated in a discussion forum related to the magazine, the JoeNet. It was not like todays forums but a mailing list. The JoeNet still existsts in it's original form today. Those were really exciting times for tube audio enthusiasts. In Sound Practices and the JoeNet ideas and thoughts about things like directly heated triodes and single ended circuits were shared. Back in the early 90ies this was pretty uncommon in the western world.

Out of that mailing list the idea for a meeting for tube enthusiasts came up which resulted in the NYnoise which was hosted by JC Morrison in New York City. At one of the early NYnoise festivals I met Dave personally the first time. This was 1999.

Back then he was already into magnetics and wound his own stuff. He put a lot of effort and energy into developing transformer volume controls. These efforts resulted in excellent sounding TVCs. More and more people got aware of Dave's work and asked him to wind stuff for him. So some years later he founded the company intact audio.

Since I'm an avid user of all things wound on iron or other metals, especially volume controls, Dave was the natural choice for supplying my needs when I started to go commercial with tube audio. I get all my volume controls from Dave. Most of them are custom made to my specs, but occasionally I use his standard TVCs too. Dave also winds inductances for me for LCR RIAAs and other stuff.

Here is a recent delivery from Dave:

Volume controls on the left side, EQ coils in the diagonal line. These are intended for the variable EQ mono phonostage I wrote about in an earlier post. More about that phonostage soon! On the right are 8 1dB/step volume controls which will be used in a passive line level crossover for fine adjustment of each channel.

On the left a close up of a 28 step TVC, with 2dB per step. Actually they are correctly called AVC for autoformer volume control. They have a single continous winding with the taps logarithmically spaced for 2dB steps. As you can imagine, these are quite tedious to wire up to a switch. Therefore I developed a solution which is relay controlled on a PCB. This version uses Dave's simpler 14 step AVCs. These are made with custom step size for me. Through alternate switching of input and output 24 2dB steps can be had from a 14 tap AVC. With the correct control scheme for the relais, this can be done with a single 24 position switch. The photo below shows such a volume control PCB:

The 14 step AVCs are wound on the same core size as the 28 step version. Pins are only located on one side. Soundwise this solution is very similar to the one with the 'big' AVC.

The core material used in the AVCs and coils is nickel. Dave's preferred material. The coils make use of the available pins on the bobbin. These are used to bring out some taps for fine adjustment of the inductance. Very simple and effective. Besides this the inductance can be controlled by simply changing the airgap or by rearranging the way the laminations are stacked. Dave can supply paper pieces of different thicknesses for precise adjustment of the airgap.

There is also a forum on Dave's site. Here you can ask questions about his stuff, place inquiries for new things and you can also find discussions about a lot of audio stuff. Check it out! Besides this site Dave also runs a blog. See my blog roll on the side bar for HiFi heroine. There you will find posts about various stuff, not only related to tubes or transformers, there is also the occasional hilarious post just about anything.

It is great to have Dave as a reliable source for my special needs for anything which needs wire to be wound on exotic materials in a special way. I also consider him as a good friend. The photo on the right shows the man himself. Keep up the great work Dave!

Best regards

Thomas

Cool Links: www.lundahl.se

Hi!

As many of you know already, I use a lot of products from Lundahl Transformers of Sweden. Lundahl is a manufacturer with a tradition of more than 50 years. They are supplying transformers mainly for the pro audio industry and also for some telecom and video applications. And of course they have a wide portfolio of transformers and chokes for tube amplifiers and peramplifiers.

So of course the Lundahl website deserves a spot in the Cool Links section. Lundahl's web page is like their products: No bling, no fancy anything, no effort spent on a shiny look. Just function! This is quite refreshing. The site has all the datasheets available you need.

There is also a list of interesting technical papers and you will find the world wide distributors of Lundahl transformers.

I've been using Lundahl products for about 15 years now and have never been dissapointed. Their products are fo remarkable quality and consistency. As mentioned above, all the cost is poured into the materials and quality of manufacturing.

On the right you see the man himself: Per Lundahl, managing director of the company. He took this position over from his father, Lars Lundahl, who founded the company with his wife in 1958.

I had the pleasure to meet Per Lundahl personnally several times. Per attends exhibitions and also audio meetings like the European Triode Festival where he held a presentation about the manufacturing of his products in 2009.

Per is a great guy, a gentlemen and excellent business partner whom I hope to deal with for many years to come.

Lundahls product portfolio for tube audio applications has been constantly growing. Per has an open ear for the needs of the audio people and comes up with several new products each year. Most of their transformers are quite flexible and allow various connection alternatives.  A good example for this is the LL1660 transformer. It can be used as an interstage or line output transformer, depending on how the primaries and secondaris are connected. Both sides can be used as primary or secondary. This offers many possibilities. The same for the input transformer LL7903 which allows connections with any ratio from 8:1 step down to 1:8 step up. The MC step up transformers typically allow two ratios to be chosen. Another nice feature: Most transformers can be ordered with specific airgaps for a wide range of primary DC current, at no extra cost.

Here is a small sampling of Lundahl's product portfolio:

So if you plan a project, check out the product catalog of Lundahl. Most likely you will find all you need in terms of transformers and chokes. These are excellent sounding products with an extremely good price performance ratio.

Best regards

Thomas

Cool Links: www.haigner.com

Hi!

I often get the question 'which speaker do you recommend, which work well with your amplifiers?'. My answer always is: Haigner. This is a small loudspeaker manufacturer situated in Vienna. David Haigner, the man behind the company, grew up in a family of musicians. But instead of making music, he chose to concentrate on the reproduction of music for his profession. He is in this business for well over 20 years.

David has a range of loudspeakers starting with the very affordable Rho. Larger models are the Tau and the now discontinued Beta. The Alpha Horn is at the top end of his range.

Have a look at his web page for details on each model. All of his speakers work very well with low powerd tube amplifiers. Their linear impedance curve is an easy load for them.

Even his smallest speaker, the Rho is a top performer. In fact I'm using this speaker myself in my small system. I usually use it to audition new amp developments. It has all it needs for this and reveals every difference between the amplifiers and preamplifiers I make. David specifies 91dB sensitivity. This seems to be not too sensitive at first sight, but David is very conservative with his numbers. I use low power SET amps with this speaker and they work even well with a 3.5W SE 801A amp if you don't need ear shattering levels.

During the 'Klangbilder' fair 2009 in Vienna, I had the pleasure to demo my amplifiers with David Haigner's speakers.  The picture on the right shows the demo system of that fair. It consisted of the Tau which is one level up from the Rho.

The speakers were driven by a Stereo 801A amp of mine which is sitting on the floor between the speakers. It uses an external power supply which is hidden behind the left speaker.

Preamplification was done by my EC8020 LCR phonostage and 801A directly heated triode linestage. Both powered by external PSUs which can bee seen behind the right speaker. The Tau was able to play at remarkably loud levels with the 3.5W of the 801A amp. This system was a perfect match and we got excellent feedback from the audience.

This is the guy who creates these wonderful speakers. The photo pictures David while he is holding a presentation at the Vienna Vibes event in summer 2010. He held an amazing lecture. Among other topics he talked a lot about room acoustics which is one of David's fields of expertise. He gave astonishing insights into this topic. The room was jam packed with people. Although that particular day was very hot and the room had no air condition, nobody wanted to miss a word and everbody stayed until the end of the lecture. And this dispite the fact that David did overun the given time slot massively well into lunch time.

I'm glad to personnally know David and have him as a friend. He is a very nice person who has a lot of knowledge to share. And of course he builds marvellous speakers.

David not only develops and sells his own speaker models. He also does consulting and custom developments for specific needs. He is also doing acoustic treatment of rooms and halls. Many public buildings like churches and townhalls, but also dance clubs have been acoustically optimised by him.

I'd like to close the article by showing David's latest creation. The brand new Gamma horn which replaces the discontinued Beta. On the right you can see this speaker with a solid maple bass cabinet and beautifully crafted horns in a white varnish on top.

As all of David's speakers the Gamma matches very well with single ended triode amplifiers. The sensitivity is specified as 98dB/1w/1m. As with all of David's spec's this is a conservative measurement. The gamma will play really loud with a 3.5W amplifier. It is even suitable to be used with a flea powerd 45 amp.

If you have not heard them yet, do yourself a favour and give David's speakers a listen. You will be up for a surprise. Contact data can be found on David's website.

Best regards

Thomas