Pass Labs build amplifiers with excessive output stages, huge heat sinks, and massive power supplies. We use the highest quality components in simple linear topologies, assembled and tested with care and subtlety. They measure well, sound great, and are reliable. Twenty-plus years of ongoing innovation have kept the X and XA amplifiers at the forefront of high-end audio.

The INT-25 embodies all this and less. A smaller stereo Class A amplifier at a lower price, it takes advantage of the lower power requirements to have simpler single-ended circuitry and fewer parts in the signal path. This also allows the elimination of degeneration, “that other negative feedback” in all stages.

Simpler and fewer gain stages improve speed and stability. Lower voltages mean the ability to run gain devices at higher bias currents, more deeply into Class A. Newer power Fet technology replaces banks of parallel small transistors with a single pair of industrial devices, each having a 700 watt / 40 amp rating. With no current-hogging issues and a new constant-current bias circuit to compensate for temperature drift, they connect directly to the loudspeaker without ballast resistors for the lowest possible distortion and highest damping factor. No degeneration also increases the efficiency and Class A operating current, allowing greater Class A operation into low impedance and reactive loads.

The simple front-end circuit uses two pairs of our favorite NOS complementary Fets in common-source mode in a current feedback (CFA) configuration.

The preamp section is a simplified single-ended version of the one used in the INT-60 and INT-250 with three line-level inputs and no line-level output.

Everything was done in the signal chain from the microphone to the loudspeaker, forever leaving an indelible mark on the music. The XA25 amplifier section is direct-coupled requiring no DC servos or frequency compensation, neither adding to nor subtracting from the experience.

As with all Pass amplifiers, the technology and construction are strictly in the service of the listening experience. The INT-25 measures superbly, but its subjective qualities are most special. In an industry where products with great specs are often found to be dry and boring, this amplifier breathes new life into the music.

The new INT-25 offers this at slightly lower power, without frills, at a lower price. It embodies new components and innovative circuits coupled with the best elements of the previous generation. The signal path from input to output has been simplified to fewer components.

Degeneration, “the other form of feedback” has been eliminated. The output stage consists of a single pair of 800 watt new generation output transistors operating push-pull Class A. We still use the same “New Old Stock” of small power JFETs and cascoded MOSFET, in the classic “CFA” voltage gain circuit. The amplifier is still DC coupled and has no frequency compensation. The result is faster, lower distortion, lower noise, higher damping and larger Class A operating envelope into low impedance loudspeakers, all in a simple 3 stage circuit with total of three pair of push-pull gain transistors.

In their ideal state, matched push-pull FETs give perfect “square law” cancellation of distortion, an effect somewhat spoiled by degenerative Source resistance used to constrain the “personality” of the devices. The removal of this form of feedback is an important element in the performance of the INT-25 and is accomplished by new approaches to stabilizing gain and bias of push-pull FETs. This gives a lower output impedance, more gain, and lower spectral content of distortion, as evidenced by measurements (see the specs section), but the more important factor is the difference it makes to the music. We observed this difference some years ago in listening tests. Degeneration removed some of the organic quality to the sound and so became the subject of further development work.

The INT-25 measures superbly, but it’s subjective qualities are most special. In an industry where products with great specs are frequently found to be dry and boring, this amplifier breathes life into the music.

Class: A
Type:Stereo
Gain (dB):29/35
Volume control:(1dB steps)63dB
Remote:yes
Inputs:3
Outputs:0
Power Output/ch (8 ohm):25 Watts
Power Consumption (W): 200
Standby Power Consumption (W): <1
Dimensions (W x H x D):17 x 17.375 x 6
Weight (LBS):49

Orders ship Sunday through Friday from our offices in Dubai, UAE.

In-stock products typically ship within 48 hours and should be expected to arrive in 3-4 business days. Orders outside of the UAE should be expected to arrive in 5-7 business days.

Pre-order and backorder products will state the approximate delivery timeline beside the Add To Cart button.

If you would like to place a custom order, chat with our specialists for a guided shopping experience. Once your order has been placed, a timeline will be provided depending on your order details.

- Free delivery within the UAE
- Shipping charges will be calculated upon checkout for orders outside of the UAE (Bahrain, Oman, Kuwait, Saudi Arabia & Qatar).
- Taxes and duties are calculated according to the applicable laws of the state or country an item is shipped to and are the customer's responsibility.

For additional information on shipping and our exchange & return policy visit our help center.

Installation charges are applicable and can be paid upon delivery for our clients based in Dubai.

- Installation Charges: AED 350 Per Hour
- Speaker Cables: AED 20 Per Meter
- Trunking: AED 10 Per Meter

For clients based outside of the UAE, please contact our specialists and we will share an estimate based on your requirements.