Power Amplifiers

Thule Audio Spirit PA100 power amplifier Thule Audio is a Danish company, specializing in audio equipment, ranging from basic entry level models, to models which are High End stuff. The product line is well thought out, and as we shall see, very rationally conceived and executed. For other reviews of Thule Audio products, look over the site. Both cases are virtually identical, and share the overall look of the entire Thule Spirit range. They are made of uncommonly thick, heavy and well finished cases, while front panels are made from 8mm thick aluminium, machined so that they have a gentle slope. In the center, one will find a "gold" knob in case of the preamp, and a decoration in case of the amp. The preamp has an alphanumeric display above the knob, which provides the user with all relevant information on power on, volume and input status in red LEDs. All this is fully remote controllable, and a remote control unit is supplied. The power amp is a very simple affair, with only a red LED power on indicator on its front side. Both units have rocker power on/off switches at the back, as they're intended to be left in standby mode all the time. [Thule PR 100 inside view] Both units share much more common componentry that I would have imagined. Both use toroidal power supplies, where the amp's toroid is rated at 500VA, while the preamp's toroid is rated at 300VA. No, you're not seeing things, it's not a typo error, I did say 300VA. That's enough for a 2x75W/8 Ohm power amplifier, let alone a simple preamp. In fact, the preamp is EXACTLY the same as the IA60 integrated amplifier, minus the power amp circuitry and heat sinks. Put another way, the preamp consists of the preamp section of the IA60 integrated. Hence the 300VA toroidal transformer - that's what they use in IA60 (see review on this site). The power amp, on the other hand, is once more the same board, but minus the preamp circuitry and with heftier power supplies - bigger transformer, and 4x10.000uF capacitors, instead of just 2x10.000uF. This is no accident, this is rational thinking. Use the same board, use the same case, use the same power supplies and you increase the numbers of your serial production, thus pushing the cost per unit down. The only thing that spoils the show is the preamp's price - it's simpler than the integrated model, but it's not only not cheaper, it's actually somewhat more expensive. That is most odd, I must say - probably for "complex marketing reasons" (a phrase I first heard in the early seventies, and it's gotten worse since then). You still have 5 line level inputs, with no option for a phono RIAA board of any kind. You still don't have a headphone output - somebody should inform the Scandinavian audio industry that headphones have been invented some decades ago, they seem to have collectively overslept that event. As usual, all input and output sockets are gold plated. Like elsewhere in Thule's product portfolio, volume and balance are controlled by a ladder of laser trimmed resistors, contained within an LM1792 digital volume control, a good point - no mechanics, no wear and tear, no aging, unparalleled precision. The amp is rated at 2x100W/8 ohms and 170W/4 Ohms - that should be enough for most of us. It has an RCA Cinch and a balanced XLR input, just as the preamp has the same outputs. Acting on logic and Thule's recommendation, I used balanced lines to link the two, except when using other units. Learn More

Triad Powersub AmpliflierTriad benchtested 5/18 good Learn More

Tru Audio MR1260 twelve channel power amplifier The MR1260 is a 12 channel, 6 zone amplifier that provides 60 watts RMS to each channel @ 8ohms or 80 watts at 4 ohms. Channel pairs can be bridged for 160 watts at 8 ohms. It features both a multi and single channel input bus with independent level controls for each channel. Has Auto -on signal sensing function. High quality Phoenix connectors allow the use of speaker cables of up to 14 gauge. Specifications: Channels: 12 channels, 6 zones Power output, continuous: 60 watts/ ch @ 8 ohms 80 watts/ ch @ 4 ohms Power output, short term: 100 watts/ ch Bridged power output: 160 watts/ ch @ 8 ohms Total Harmonic Distortion: 0.05% Signal to noise ratio: Great than 100dB Frequency range: 18 Hz. to 50k Hz. @+ - 2 dB Damping factor: Greater than 400 Input impedance: 20K ohms Certifications: CE, CSA Dimensions: 5 ¾` H, 17` W, 17` D Weight: 46.9 lbs Learn More

Power output: 100 watts (mono) Frequency response: 20Hz to 20kHz Total harmonic distortion: 3% Signal to noise ratio: 95dB Speaker load impedance: 2Ω to 8Ω Valve complement: 4 x EL34, 2 x 12AT7 Dimensions: 400 x 300 x 180mm Weight: 22kg Learn More

VTL MB-185 Monoblock Power Amplifier Output Power: Tetrode = 230 Watts Triode = 120 Watts T.H.D. 20 Hz - 20 kHz @ 230W: Tetrode = < 2.5% T.H.D. 20 Hz - 20 kHz @ 120W: Triode = < 2.5% Input Sensitivity @ 125 W: 1.7 V Input Impedance: 130,000 Ohms Optimum Load Range: 2 - 8 ohms S/N Ratio @ 125W, tetrode: -110 dB, 120 HZ S/N Ratio @ 60W, triode: -110 dB, 120 Hz Power Consumption: Idle = 180 W Full Power = 600 W Primarv Mains Fuse Rating: 100/120V = 10A Ceramic Slo Blo 220/240V = 5A Ceramic Slo Blo B+ Fuse Rating: 1A ceramic Slo Blo Dimensions - EACH: W = 19 inches (48cm) D = 12 inches (26cm) H = 9 inches (23cm) Weight - EACH: 56 lbs (25Kg) per monoblock {total 65 lbs (30 Kg) packed} Learn More

VTL MB300 monoblocks, price per pair Rebuilt by Blackie Pagano with paperwork. Work well Description: Tubed monoblock power amplifier. Rated power: 300W (no load specified). Power bandwidth: not specified. Frequency response: not specified. Sensitivity: 775mV RMS. Source impedance: 0.1 ohm. Dimensions: 19" W by 10" H by 10" D. Weight: 75 lbs each. Learn More

mAMP Features Utilizes latest generation (ASX2) ICEpower® audio technology 250w in 8Ω 430w in 4Ω External selectable mains voltage 115/230VAC Idle power consumption 9.5w Thermal protection Differential, fully balanced Over current protection Sound optimized soft clip Robust construction Standard 12V DC Trigger Machined and anodized aluminum front panel Gold Plated unbalanced (RCA) input Neutrix Balanced (XLR) input 3rd Generation fully balanced input stage with impedance of 100k Compact size (8"W x 3.5" x 8"D) 8 lbs. Covered by a 5 YEAR WARRANTY mAMP Specs Typical THD+N 8Ω (10W out): 0.002% Power Output 8Ω @ 0.2% THD+N: 250W Power Output 8Ω @ 1.0% THD+N: 277W Power Output 4Ω @ 0.2% THD+N: 430W Power Output 4Ω @ 1.0% THD+N: 460W Output Idle Noise: <125µV Frequency Response 20Hz-20kHz: ± 0.1db Lower Bandwidth: 1.5Hz (All Loads) Balanced Input Impedance: 100kΩ Unbalanced Input Impedance: 100kΩ Dynamic Range: 111db Gain: 30db Sensitivity: 1.31V Output Impedance: 0.018Ω Min Load: 3Ω Max Output Current: 30A Idle Power Consumption: 9.5W Standby Power Consumption: <0.5W Learn More