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Universal Stereo Tube Output Stage (need to add two 2.2uF coupling caps)

Universal Stereo Tube Output Stage

Price: $149.00

Universal Stereo Tube Output Stage (UTS)

Design and performance

Complete module including the specially designed over spec power transformer for 115 to 240 V operation. Hybrid anode follower with circle of two CCS using ECC88/6922/6DJ8/6H1/6CG7 (not included); S/N ratio > 100 DBA, 2V RMS into a 10K THD is around 0.1%, 20 Hz to 20 KHz <-0.5db, output minimum 10V RMS on clip into 10K load <1% THD, output impedance is 75-100 ohm; Also includes Obbligatto coupling capacitor.

Application

one board can do stereo RCA output tube stage for a DAC, two boards can do balance output tubes stage DAC. One board could make a nice simple line stage, two boards could be configured as a balanced line stage, or an RC RIAA between two boards would make a nice phono stage with about 40 DB of gain, or two boards with a 10K LCR and a 10K termination resistor would be an easy way to build an LCR phono stage.

Tube used

ECC88/6DJ8/6922/6H1/6CG7 only. Do NOT fit 6H30 or 6H6

Dimensions

140 mm x 80 mm x 45 mm

Installation instruction:

Here is the manual in all of its glorious 39 pages! It gives detailed instructions for using the UTS as a voltage or current output DAC, single ended or balanced line stage with 6 or 12 DB gain, and instructions to implement as a moving magnet single ended stereo RIAA EQ preamplifier. In addition to the instructions provided it is also possible to use the UTS as a single or balanced tape head stage, classic high gain two channel transformer coupled microphone preamplifier, and input and summing amplifier such as a classic tube mixer.

NOTE :This is for the purchase of the module without the power transformer, without 2.2uF coupling caps and without the tube.

Showcases:

Click link to view:

Universal Tube Output Stage Installation Manual

The Vinyl Song Universal Tube Output Stage EZ Phono Installation Manual

Instructions for Projekt UTS linestage

For other shipping options, Check our Website by clicking the icon below:

Store

online store

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EZ UTS-Projekt Phono-Sweet Sounds

EZ UTS-Projekt Phono

Yesterday we got the UTS EZ linestage with Extensions into the system.

The shaft extensions make a difference: sound is improved

1. more immediate, micro-macro dynamics resolved more easily, big transients seem strike from out of nowhere and delicate sounds present themselves with noticeable finesse
2. self-noise has dropped significantly; ~0.2mv which is close to our limit to measure and maybe explains some of #1
update: with 0.4mm copper tube shield in place, grounded to chassis it drops to 0.1mv!
3. The tactile quality of switch action is much improved due to the effect of the flexi connection between shaft and switch. IMO clunky switching puts the ears in a bad mood

We will still try some other enhancements:
coupling caps – we have the obbligato tin foil and a sample pair of paper-in-wax aluminum foil (huge)
tube shield, et

 

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EZ UTS-Projekt Phono

EZ UTS-Projekt Phono

EZ UTS phono stage.

As shown in the UTS manual. Basically a 2-UTS-modules-in-series-and-RIAA-network sandwich.

EZ

We found it needs 2 power transformers. Reason: to break ground loops and forestall AC filtering imbalance since in a phono stage noise is a paramount issue.The transformers are placed in a separate steel box for shielding.

AC wires need to be shielded and the shield connected to IEC chassis ground (anyone know any good spooled AC cord with 100% shielding?).

Result: state-of-the-art low noise (0.1mv self noise) and big dynamics tube phono stage with about 36-38db gain (depending on tubes)

And – it’s EZ!

The recipe:
Large Project box with feet, connectors and switches etc
Steel enclosure for power transformers
2 UTS modules and 2 power transformers
RIAA parts
AC wire braided shield

Assemble, connect, plug and play!
EZ and no noise tomfoolery.

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Wedding Bells at DIYHFS

Wedding Bells at DIYHFS

The happy couple:
UTS (Universal Tube Stage)
+
UVC (Ultimate Volume Control)

Their happy home:
240mm Projekt Bungalow

The marriage proceedings couldn’t have worked out better and one would wish all weddings were like this one.

Yes it’s still the honeymoon but this one promises to go the distance. This couple were truly made for each other.

I usually cry at weddings but this one makes me smile.

 

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When is Ultimate Ever EZ?

VCall2M-230x230

 

Now.

Check this out:
at the front we have the controls and the power supply. All the digital bits flow across those ribbons to selector (left), volume (right) and the audio signal board (chassis back).

The audio signal board uses end-to-end analogue potentiometers to adjust volume and vacuum silver relays to select source. The great thing is the audio signal board can be mounted beside the I/O jacks and the power supply can be put far away. This minimizes noise and maximizes musical fidelity.

Quiet it is. Next week I’ll report some measurements.

Now notice the 2 little round circles with roach-like occupants, flanking the 2 red caps on the audio board. Those are the LSK389 JFET so that the JFetted outputs can drive any load (Zout 50 ohms!). But, these can be bypassed with the direct out connection going to another set of outputs. You’d want to keep the cables very short if used direct out.

EZ.

We will also offer a CNC’d front plate just like you see to premount the Control matrix board (the one attached to the knobs) to be used with your own chassis.

EZ’r.

Now how about those 127 steps? It’s the first time we’ve ever had a device with 127 step attenuation. It’s like having 5.5 x 23 step volume controls. What’s it like to use? Jailbreak! Really. It’s like the difference between looking at the world through prison bars or looking out a panoramic window.

And the sound: surprisingly smooth. Why surprisingly? Because it ain’t got tubes! But it is passing along 100% of the tube-sound upstream.

More.

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Universal Tube Output Stage Installation Manual

Universal Tube Output Stage Installation Manual

Table of Contents

Specifications

1 – Power Supply Wiring

Muting

2 – Output Connector Wiring

Stereo Single Ended Connection

Stereo Balanced Connection

3 – Input Wiring and Module Configuration

3.01 / 3.02 – Settings and Input wiring for current output DAC, stereo, single ended, 0V reference voltage, 1mA / 2mA full scale current

3.03 / 3.04 – Settings and Input wiring for current output DAC, dual mono, single ended, 0V reference voltage, 1mA / 2mA full scale current

3.05 / 3.06 – Settings and Input wiring for current output DAC, balanced mono DAC’s, balanced output, 0V reference voltage, 1mA / 2mA full scale current

3.07 – Settings and Input wiring for current output DAC, stereo, single ended, 1mA full scale current, ~2.5V reference voltage

3.08 – Settings and Input wiring for current output DAC, balanced Stereo DAC’s, balanced output, 1mA full scale current, 2.5V reference voltage

3.09 / 3.10 – Settings and Input wiring for current output DAC, balanced Stereo DAC’s, balanced output, 4mA full scale current, 2.5V / 0V reference voltage

3.11 / 3.12 – Settings and Input wiring for voltage output DAC, stereo, single ended, 1…1.5 VRMS full scale output voltage, 0V / 2.5 Vreference voltage

3.13 – Settings and Input wiring for voltage output DAC, stereo, balanced output, 2…3 VRMS full scale output voltage, 2.5V reference voltage

3.14 – Settings and Input wiring for single ended stereo output from voltage output DAC, stereo, balanced output, 2..3 VRMS full scale output voltage, 2.5V reference voltage

4 – Other applications of the Universal Tube Output Stage

Settings and Input wiring for use as SE Linestage 6db Gain

Settings and Input wiring for use as SE Linestage 12db Gain

Settings and Input wiring for use as Balanced Linestage 6db Gain

Settings and Input wiring for use as Balanced Linestage 12db Gain

Settings and Input wiring for use as simple single ended stereo RIAA equalisation preamplifier

Alternate 12db Gain Stage in Shunt mode

Pro-Audio Project

Introduction and Overview

The Universal Tube Output Stage has been designed to offer a State of the Art tube amplification stage, mainly intended to be applied to CD-Players, DVD-Players and DA-Convertors to completely replace the original solid state analouge circuit

Additional applications include the use as Line Preamplifier with 6dB or 12dB gain.

The module can also be used as low noise, high gain (gain appx. 30db) amplification block for low level applications such as RIAA pre-amplification stages and as microphone or instrument amplifier.

Using one module we have either a stereo single-ended input and output (two independent channels) or a mono balanced input and output (single balanced channel). If a stereo balanced input and output are required two modules must be used.

Each configuration can be used either as single ended in/out stereo for one PCB or as balanced in/out per PCB.

If using a balanced output DAC with a single ended input Tube output an additional resistor or resistor/capacitor needs to be added externally to the tube PCB.

All DAC types listed below names the most commonly encountered types, but is by no means exhaustive.
Some examples:

1) Analog stage for current output DAC – 2V out for 0dbfs with 1mA or 2mA full scale current, can be configured for DAC’s having their output referenced to either ground (TDA1541, PCM56/63/1702/1704, AD1856/1862/1865) or an arbitrary reference voltage of 2 – 3V (TDA1543/1545, PCM1738,AD1853 and many others) , < 100R output impedance.

2)Analog stage for voltage output DAC – 2V out for 0dbfs with 1V or 0.5V full scale voltage, can be configured for DAC’s having their output referenced to either ground (CS4328) or an arbitrary reference voltage of 2 – 3V (CS4329/9X; PCM1716/1728/1732/1741; AKM4393/4394/4395; AD1852/1854/1855; NPC SM5872/5865/5866 et al) , < 100R output impedance.

3)General high level gainstage – 6db gain, inverting output, >400KOhm input Impedance, < 100R output impedance

4)General high level gainstage – 12db gain, inverting output, >200KOhm input Impedance, < 100R output impedance

5)General low level gainstage (Microphone, Phono, Tapehead etc.) with around 30db gain and > 40KOhm input impedance, < 100R output impedance

Some possible applications past the use as line stage (obvious) or DAC output stage
(equally obvious):

Single Ended MM Phono Stage – 2 Modules, add a RIAA EQ of 10K or higher impedance at low frequencies (calculator @ http://kabusa.com/riaa.htm) or 10K RLC EQ… (add pre-pre or MC stepup TX for MC)
Balanced MM Phono Stage – 4 Modules, add a balanced RIAA EQ of 10K or higher impedance at low frequencies (calculator @ http://kabusa.com/riaa.htm) or 10K RLC EQ… (add pre-pre or MC stepup TX for MC)

Single Ended Tape Head Stage – 2 Modules, add a NAB etc. EQ of 10K or higher impedance at low frequencies (calculator @ http://kabusa.com/riaa.htm) or 10K RLC EQ…

Balanced Tape Head Stage – 4 Modules, add a balanced NABetc. EQ of 10K or higher impedance at low frequencies (calculator @ http://kabusa.com/riaa.htm) or 10K RLC EQ…

Classic high gain 1-Channel transformer coupled Microphone Preamplifier using 1:4/5 input transformer and 5/4:1 transformer balanced output with level control between stages – 1 Modules – maximum gain ~60db.

Classic high gain 2-Channel transformer coupled Microphone Preamplifier using 1:4/5 input transformer and 5/4:1 transformer balanced output with level control between stages – 2 Modules – maximum gain ~60db.

Classic low gain 2-Channel transformer coupled Microphone Preamplifier using 1:4/5 input transformer and transformerless balanced output (10K load) – 2 Modules – maximum gain ~40db.

Classic high gain 2-Channel transformer coupled Microphone Preamplifier using 1:4/5 input transformer and transformerless balanced output (10K load) with level control between stages – 4 Modules – maximum gain ~72…75db.

Input and Summing Amplifier in a classic tube mixer, for example, a 6 – 2 mixer could be build using 6 Microphone transformers(plus instrument input jacks), 3 tube stage modules for inputs, suitable volume and pan control faders/potentiometers per chnnel and one tube output module with 4/5:1 stepdown output transformers fo balanced output… Maximum gain in to out using 1:4/4:1 transformers is around 60db.

For ease of application all connections on the Universal Tube Output Stage are provided as screw terminals and all configurations are handled by gold-plated jumpers, so no soldering is required on the actual Universal Tube Output Stage Module.

For those desiring soldered connections instead we recommend to either unsolder the screw terminals and solder the wires in the holes thus available or to simply solder the wires to the solder pads below the PCB.

Equally, for those wishing a soldered configuration instead of jumpers simple solder bridges can be soldered across the jumper pins below the PCB.

In the following Manual the application of the Universal Tube Output Stage is broken down into three distinct sections.

Section one covers the connections of the included power supply transformer while section two covers the connections of the output sockets to the module.

Section three covers the different arrangements of the Input connections and the jumper configuration to suit the various available DAC Chips and the other applications.