Transcendent Sound       Vacuum Tube OTL Audio Amp Kits

The Pinnacle OTL

300B Push Pull Tube Amp

6 watts into 8 ohms

10 watts into 16 ohms

The Finest Sounding Amp We Have Ever Produced

Combines the sonic magic of the legendary 300B with

the incredible accuracy and realism of OTL technology.

Virtually Dead Quiet

Outstanding Peak Power

Works with virtually any 8 ohm speaker with a sensitivity of 90dB/watt or greater.

Full Kit Only $1699 per pair without tubes.

Available with Grey or Black Front Panel


For over 20 years, Transcendent Sound has pushed the envelope in high-end sound reproduction.  This time the envelope has been ripped apart.  The Pinnacle is the result of 20 years of constant improvements in pursuit of ever higher quality in sound reproduction.  The 300B is world renown for the weight and body that it provides.  OTL is famous for extreme realism, accuracy and naturalness.  By marrying the two, the best characteristics of each are retained.  The result is a musical experience unmatched anywhere.  Once the music starts, you wont want to turn it off.

Using a 300B in an OTL circuit is very difficult.  A 300B triode has a directly heated cathode.  This places the filament in direct electrical contact with the speaker.  We have developed new circuitry which has overcome these limitations and created a new level of amplifier performance.  It is ideal for use with most any moderately efficient speakers.  There is no buzz. The amp is virtually silent.

The 300B has amazing peak power.  Listening to it, you would never believe the power rating measures that low.  Bass transients are full and powerful.  The top end is crystal clear and lightning fast. Midrange is silky smooth without any harshness or bite.  The amp mates perfectly to the DIY speaker projects shown on this web site.  Vinyl come to life when played through this amp.

The 300B is an expensive tube, but is extremely long lived and stable.  Since it is a three element tube, (plate, grid and cathode/filament), many tube failure modes are eliminated.

The amp incorporates the latest is transient protection devices which protect your speaker and itself no matter what kind of component failure occurs.

This amp truly is a breakthrough in tube audio technology.  But then again, it’s a Transcendent Sound product.  That’s what we do.

The top is the noise spectra.  The subsonic signal below 20 Hz is room rumble and is inaudible.  The first spike at 60 Hz is AC hum and only measures 80 microvolts which is inaudible.  The next is at 120 Hz at only 270microvolts.  The next is at 240 Hz at 280 microvolts which has the highest probability of detection but that would require sticking your ear against the speaker grill in a dead quiet room.  All other noise components are below 150 microvolts and most are below 100 microvolts.  The amp is essentially noiseless.

The lower image shows harmonic distortion at half power at 500 Hz.  There is a small distortion component at the second harmonic 50 dB down, another small one at the third harmonic 56 db down and then nothing.  The amp is very clean.

Specifications:

Tube complement: 4-300B, 1-12AX7, 2-12AU7 for each amp.  No mesh plate tubes.  Use only full 40 watt rated 300B tubes.

Power output: 6 watts into 8 ohms, 10 watts into 16 ohms.

Bandwidth: Flat from 20 Hz to 50 kHz at full power.

Signal to Noise Ratio:  Greater than 90 dBA.  See diagram above.  No buzzing.  No hissing.

THD: Less than 0.5%

Input Impedance:  100K

Input Sensitivity: 1.4 volts for 6 watts into 8 ohms.  2.5 volts for 10 watts into 16 ohms.

Gain: 14 dB or 5 times.

Size: 17 by 10 inch footprint.  With tubes, 9 inches tall.

Power consumption:  320 watts for a pair.  

Voltage: 120V or 220 to 240 volts, 50-60 Hz.

Weight: 16 pounds each, 32 pounds for both amps.