211 Drives 211, Part 2

Hi!

Assembly of the 211/211 amplifier has begun. The metal plates for the internal construction are done. These will carry all the parts and will be stacked in a sandwich fashion. As mentioned in the first part, this time a completely new chassis design will be used. Even a new shape. It will be round:

The photo above shows the top plate with the tubes plugged in.

These are all the metal plates for the sub assemblies for the amp:

Cutouts for sockets, capacitors, connectors, etc. And screw holes for transformers and chokes.

After the parts are attached it looks like this:

These are the assemblies with output and interstage transformer (left) and the last stages of the B+ filtering. Oil caps for the filtering and ultra path connections.

Capacitors are mounted to the plates with aluminium rails on the under side:

Filament and B+ chokes are on the bottom plate (left):

The bottom plate also carries all connectors. Input transformer and bias resistors are mounted on the underside of the top plate (right).

The Connectors will be accessible from the bottom:

Stay tuned for updates as the construction progresses.


Best regards

Thomas

Music: Deodato, Also sprach Zarathustra

Hi!

I have been browsing through my record collection recently and pulled out some records which I used to like a lot a long time ago. It is quite interesting to listen to some of the favourites of one's youth through the distance of time. While some appear quite dusted now, some music seems to resist the passage of time and sounds as fresh as decades ago. In some of my old favourites I now can find new aspects which I didn't realise in the past. I am going to present some of those records in the next few posts of the Music series.

I'd like to start with Deodato's rendition of 'Also Sparach Zarathustra':

Also Sparach Zarathustra was composed by Richard Strauss. It is a classical piece which became famous to a broader audience when it was used in the sound track of Stanley Kubrick's film '2001 A Space Odyssey'. The Brazilian musician Eumir Deodato created a jazz/fusion/funk version based on Strauss' theme.

Originally this piece was published on Deodato's album 'Prelude' in 1972. His version of Also Sprach Zarathustra was very successful and made it to #2 in the U.S. billboard charts. Quite a remarkable success for an instrumental jazz single. The record I have is named after the famous title and was published by Creed Taylor, Inc (CTI) and distributed in Germany by Metronome Musik GmbH. The Record starts with the main title. It opens with some percussion and electronic bass sounds resembling the opening of the original. Then an electronic keyboard supported by electric guitar in the background kicks in and the original theme is played by a brass section. Once that part is done it changes considerably with a short bass guitar solo, followed by a very funky keyboard solo. As the keyboarder gets carried away, guitar and brass section join again. The best part starts when the solo is handed over to an extremely funky guitar. It is hard to sit still during this part and not to get up and play the air guitar.

Most of the other titles are equally good. The second title 'Do it again' does exactly that. It starts as funky as the first one ended.

Deodato reinterprets other classical pieces as well like Maurice Ravel's Pavane for a dead Princess or Gerhwins Rhapsody in Blue. Each in the same funky style.

While some aspects of the music, especially the funky guitars and keyboards are clearly 70ies style, the whole album sounds remarkably fresh. 70ies funk is quite popular again for a good reason. Also in terms of sound quality the record is very good with lot's of detail, tone colours and no exaggerated harsh treble which was common in many recordings of that era. Very listenable in terms of music and recording quality.

Best regards

Thomas

Making of a 801A / 211 Amplifier, Part 6: More Listening Impressions - Weitere Höreindrücke

>>> deutscher Text weiter unten, german text below <<<

Hi!

As many of you know, I am not very comfortable writing about the sound of my own creations. I prefer to let others speak. The owner of the 801A / 211 amplifiers was so kind to share his impressions and allowed to publish them on my blog.

This is his listening report, the original german text can be found below.

As the new owner of the Thomas Mayer Elrog 211 SE amplifiers I have some good and some bad news to share: First the good news: This amp is a hit! And now the bad news: The Hirata-Tango transformers used in these amplifiers are not made any more since a long time also the production of the ISO-Tango transformers has ended in the mean time. But there are still some few pairs of them in Thomas' stock in Lindau.

What has changed in my system after adding these amplifiers? The 25W per channel (up to 20W in Class A1 and 5W 'reserve' going to Class A2) is in a totally different league than the 1.5W of the SE 45 I used before. You might think now : Ah yes, those amps have so much power they are not really able to walk any more. Not true! The 211 SE amps with the tubes from Lübtheen (Elrog) can reproduce very subtle nuances, if the music material demands that. This was the biggest surprise for me. I could now use the whole array of silly audiophile adjectives about the sound but would still not be able to describe the core of the performance. Of course they have an extremely controlled and black bass, silky mids and a clear and extended treble range. Focussing is precise as never before in my system. The layering of the instruments in width and depth is extraordinary. The dynamics are monster! Did I forget something?

Such descriptions fit a number of amplifiers, but the 211 SE can do more and you don't have to worry about all those points above. Everything is just there. I don't know if a 45 SE is able to provide a tad more resolution. I don't care with all I got now. The 211 plays along with the same charm as my previous 45 had. And I didn't expect that to be possible.

If the rest of the system is up to the task the result has less to do with HiFi but rather with realistic music reproduction. I never heard all the power and tone colours of a concert piano so convincing before. Tonal nuances between a Bechstein, Brodmann or Steinway are very easy to hear. Often these instruments sound like toys when played through a HiFi system.

The naturalness of the reproduction is very apparent with live recordings. Is the applause realistic or does it sound as if the audience is clapping with logs of wood? The 211 SE shows how it is supposed to sound. Here the resolution capability plays an important role. Another aspect which I only realised after a while: Mediocre recordings get new live with the 211 SE amps. What sounded flat and featureless before now gets some fresh excitement. Of course the 211 SE cannot make a silk purse from a pig skin. But it is surprising what it can pull out of such recordings.

A solo violin is always very difficult. This instrument has an extended harmonic spectrum. Rarely can it be realistically reproduced. Again the 211 SE shows how it's done. The amps keep everything in order during complex music parts like orchestral tutti. It doesn't run out of steam like flea power triodes do. These amplifiers might open new doors for Wagner fans. I could go on with this list. I have not found any weakness.

I can't say if it's the Hirata Tango transformers, the extraordinary Elrog 211 or the circuit. For sure it is the overall concept which is responsible for the performance.

Too much praise? I don't think so. I have never heard any amplifier before which is more convincing.

Thanks to J.S. for his in depth report. I am glad you enjoy the amps!
As he mentioned, sadly ISO Tango is stopping their business. At this point it is not clear if that is temporarily or if they are going out of business permanently. I still have some of the superb Tango X10S transformers in stock for a very few more of these amplifiers.

Hallo!

Da ich ungern selbst über den Klang meiner Verstärker schreibe, ziehe ich es vor wenn andere Ihre Höreindrücke wiedergeben. Der Besitzer der 801A / 211 Verstärker war so nett seine Klangeindrücke niederzuschreiben zur Veröffentlichung auf meinem blog.

Hier der Hörbericht:

Als neuer Besitzer der Thomas Mayer Elrog 211SE habe ich eine gute und eine schlechte Nachricht, zuerst die gute: das Ding ist der Hammer! Und nun die schlechte: die hier verbauten Hirata Tango Übertrager gibt es schon lange nicht mehr und auch die neuere Produktion ISO-Tango wurde mittlerweile eingestellt. Allerdings sind wohl einige wenige Übertrager noch in Lindau auf Lager.

Was hat sich nun mit der Endstufe in meiner Kette verändert? Zunächst einmal ist sie mit ihren 25 Watt (20W in Class A1 und dann noch 5W 'Reserve' in Class A2) ein ganz anderes Kaliber als die 45 mit 1.5 Watt Ausgangsleistung. Kennen wir schon, wird der eine oder andere vielleicht denken, kann vor lauter Kraft nicht laufen! Von wegen! Die 211SE spielt zusammen mit der Röhre aus Lübtheen unheimlich filigran, wenn die Musik das fordert. Das war für mich die größte Überraschung. Man könnte nun eine ganze Breitseite an Hifischwachsinn loslassen, was den Klang anbelangt und doch den Kern der Performance damit nicht treffen. Natürlich hat sie einen extrem kontrollierten und schwarzen Bass,  samtige Mitten und einen klaren, ausgedehnten Hochtonbereich. Die Fokussierung ist präzise wie noch nie, die Staffelung der Instrumente in Breite und Tiefe hervorragend. Die gebotene Dynamik ist ein Monster! Habe ich etwas vergessen? 

Solche oder ähnliche Beschreibungen passen natürlich auf eine Vielzahl von Endstufen.

Nein, die 211SE kann viel mehr, nämlich Musik machen! Ohne dass man sich über obengenannte Punkte Gedanken machen muss. Es ist einfach alles wie selbstverständlich da. Ob nun eine 45 vielleicht doch noch einen Hauch mehr Auflösung bieten könnte, weiß ich nicht, ist mir aber im Zusammenhang mit dem Gebotenen auch völlig egal. Auf jeden Fall kann die 211SE mit dem gleichen Charme spielen, wie meine 45 früher. Und das hätte ich bisher nicht für möglich gehalten.

Wenn der Rest der Kette mithalten kann, kommt eine Wiedergabe zustande, die weniger mit HiFi zu tun hat, sondern mehr mit realistischer Musikwiedergabe. Die ganze Wucht und die Klangfarben eines Konzertflügels habe ich über eine Musikanlage noch nie so überzeugend gehört. Tonale Feinheiten eines Bechstein, Brodmann oder Steinway Flügels sind sehr einfach zu hören. Meistens klingen diese Instrumente über eine Hifianlage mehr nach Spielzeug.

Wie natürlich die Wiedergabe ist, kann man auch sehr deutlich bei Live Konzertmitschnitten hören; klingt der Applaus realistisch oder hat man das Gefühl, die Zuschauer würden Holzscheite aneinander schlagen? Die 211SE zeigt uns, wie es klingen sollte. Hier spielt natürlich das Auflösungsvermögen eine entscheidende Rolle.

Eine andere Sache ist mir im Laufe der Zeit aufgefallen; mäßige Aufnahmen, die eher ein Schattendasein führten, bekommen mit der 211SE neuen Elan. Was vorher flach und strukturlos war, bekommt plötzlich eine spannende Note. Natürlich kann auch die 211 aus einem Schweinebauch keinen seidenen Geldbeutel machen, wie die Amerikaner sagen. Aber es ist erstaunlich, was aus diesen Scheiben noch herausgeholt werden kann. 

Schwierig ist immer die Wiedergabe einer Solovioline, dieses Instrument hat ein ausgedehntes Obertonspektrum, womit eine realistische Darstellung nur in wenigen  Fällen gelingt. Auch hier zeigt die 211SE wo es lang geht. Bei komplexen Musikpassagen wie Orchestertutti behält die Endstufe den Überblick und gerät nicht ins Schwimmen wie dies bei Kleinleistungstrioden oftmals der Fall ist. Für Wagner Fans könnten sich hier neue Dimensionen eröffnen. Die Liste könnte man nun endlos weiterführen, einen Schwachpunkt habe ich bisher noch nicht entdeckt.

Inwieweit nun für diese Performance die Hirata Tangos, die hervorragende Elrog211 oder die Schaltung eine Rolle spielen kann ich nicht sagen. Es ist sicher das Gesamtkonzept das zu diesem stimmigen Verstärker führt.

Zuviel des Lobes? Eher nicht, eine überzeugendere Endstufe hatte ich bei mir bisher noch nicht gehört.

Vielen Dank an J.S. für diesen detaillierten Bericht! Es freut mich sehr, dass Du diese Verstärker so geniesst.

Wie in dem Bericht erwähnt, stellt ISO-Tango leider die Produktion ein. Ob nur vorübergehend oder für immer ist momentan nicht bekannt. Ich habe noch welche von den hervorragenden Tango X10S Übertragern auf Lager für einige wenige weitere solche Verstärker.

Viele Grüße

Thomas

211 Drives 211, Part 1

Hi!

After the 801A / 211 amplifiers are successfully finished, the next project based on the 211 transmitting triode is in progress. This time with an even beefier driver tube, another 211! Of course the german made Elrog ER211 tubes will be used again.

Back in the 1990ies I already built such an amp, which was shown in the famous Sound Practices magazine. Unlike the old one, the new build will get a less extreme power supply. Instead of a three phase supply it will use a more widely usable single phase supply.

Still the size and weight will be quite significant and surpass the 4 chassis 801A / 211 amps. These are all the main components which will go into the amplifier chassis of one channel:

Instead of the Tango output and interstage transformers, Lundahl types will be used. The first build of this amp will be a test bed for the version with all silver transformers. Once the amp is finished and performs satisfactory, it will be rebuild with silver.

The power supply uses similar parts as that of the 801A / 211 amps :

The only difference will be the use of a hybrid rectifier bridge with 866A mercury vapour and 6CG3 TV dampers. Similar as in the PSU of the UX201A Sound processor.

Quite a challenge to fit all these parts into their chassis. These special amplifiers deserve their own unique chassis style. Stay tuned for progress updates about the 211/211 amps.

Best regards

Thomas

RIAA, NAB & IEC Equalisation

Hi!

This is a project which got delayed a bit but I finally found the time to finish it during the holidays. It is a passive LCR EQ unit which covers RIAA for LP playback as well as NAB and IEC tape equalisation.

For IEC, both 15 ips (inch per second) and 7.5 ips curves are implemented. All networks are built as 600 Ohm LCR EQ filters. Thus they need a low impedance preamp to drive them. This particular unit will be used with a DHT preamp. But it could also be used with the multi chassis modular preamp which was intentionally split up to allow the use of different EQ modules. This way the same preamp can be used as phono preamplifier as well as tape preamplifier, which gets fed from the tape head.

The chassis style is the same as that of the modular preamp series:

Just a simple rotary selector switch at the front which switches the different EQ networks in and out of the signal path.

Nothing fancy on the backside. Just inputs and outputs and a ground post to ground the chassis.

The RIAA network follows the conventional approach. It contains two LCR filters. One for the 318/3180uS time constants (50/500Hz corners) and one for the 75uS time constant (2122Hz corner frequency).

The network for NAB equalisation only has two corner frequencies at 50Hz (same as RIAA) and 3180Hz (3180 and 50uS). So it requires only one LCR network. Since it shares the same low frequency corner with RIAA, but has a higher upper frequency corner it's attenuation is higher at 1kHz.

The two IEC curves for 7.5 and 15 inch per second tape speeds actually only have one corner frequency since they don't have a low frequency shelf. But for practical reasons a low frequency corner had to be chosen at which attenuation starts. Otherwise the inductances would have to be infinite. The low frequency corner has been chosen at around 20-25Hz. The high frequency corners are at 2274 Hz (70uS) for 7.5ips and 4547Hz (35uS) for 15ips. Due to the lower shelf frequency the attenuation at 1kHz is higher for the IEC settings.

Here a photo of the internals:

I have another variable EQ design in the planning which will have many EQ settings to cover most curves for old shellac and vinyl mono records. This design will be based on the Octal Phono Preamplifier circuit. Stay tuned!

Best regards

Thomas