Product Description
Soviet Pentode | USSR NOS Tube Pentode Colour Module
- Thermionic Valve Saturation Colour Module
- Class A Operation
- Pentode / Triode Mode
- NOS Military Grade USSR Tube
- Low Power Consumption
- Low Voltage – Safe to Use
- On-Board Regulator and Filters
- Compatible with DIYRE Colour Format
The Soviet Pentode is a true Class A tube saturation Colour Module. The Soviet Pentode is built with sub-miniature, military-grade, USSR made, NOS thermionic valve.
The Soviet Pentode can operate in Triode or the Pentode Mode. Each mode offers different Saturation characteristic which results in different tonal results.
The Triode Mode has lower gain, produces mainly second harmonics and the sound is warmer, more mellow.
The Pentode Mode delivers 3dB higher gain, overdrives much quicker, produces more of 3rd and 5th harmonics and the sound is more bright and crisp.
Both Operation Modes add natively occurring tube compression.
The Module does not use any DC/DC converter and does not contain dangerous high voltage.
Low-Power Miniature Valve
The Soviet Pentode Colour Module uses the Low-Power NOS Military Valve designed for operation in Low-Voltage conditions.
No under-voltage of the Tube is happening. The Soviet Pentode valve works according to the specification sheet producing a rich palette of harmonics.
Important User Note!
The Soviet Pentode requires time to heat-up. Allow 5 minutes wait time to ensure proper operation of the Tube Colour Module.
HD Audio Samples
Stranger Synth - Dry
Stranger Synth - Soviet Pentode - Triode Mode | More Drive
Stranger Synth - Soviet Pentode - Triode Mode + Discrete Line Driver | More Drive
Stranger Synth - Soviet Pentode - Pentode Mode + Discrete Line Driver | More Drive
E-piano - Dry
E-piano - Soviet Pentode - Triode Mode | More Drive
E-piano - Soviet Pentode - Pentode Mode | More Drive
E-piano - Soviet Pentode + Discrete Line Driver - Pentode Mode | More Drive
Drums - Dry
Drums - Soviet Pentode - Pentode Mode | More Drive
Drums - Soviet Pentode + Discrete Line Driver - Pentode Mode | More Drive
Track Mastering - Dry
Track Mastering - Soviet Pentode - Pentode Mode
Track Mastering - Soviet Pentode + Discrete Line Driver - Pentode Mode
The US Pentode Compared to the Soviet
The US Pentode Colour Module shares some similarities with the Soviet Pentode Colour Module. Both Colour Modules have the Pentode/Triode selectable operation mode and can operate at lower, safe voltage without sacrificing the performance.
The difference is in the type of tonal results which both tube colour modules can provide.
The Soviet Pentode produces darker and a bit lo-fi tone, especially in the Triode mode. If you are looking for an old-school sound for your synth or vocal, the Soviet Pentode is a perfect choice.
The US Pentode will produce more “Hi-Fi” tone, brighter, with a glass-like shine. If you wish to add some sparkles to the guitar or vocal, you should choose the US Pentode.
Learn more about the US Pentode ->

HRK Soviet Pentode vs LTL Pentode Colour Module
Colour Module
|
HRK Soviet Pentode
|
LTL Pentode Colour Module
|
Valve
|
USSR NOS Pentode |
NOS Raytheon 6418 |
Pentode Mode
|
Yes |
Yes |
Triode Mode
|
Yes |
No |
Discrete Components
|
Yes |
No |
Integrated Circuits
|
No |
Yes |
Comparison between LTL Pentode Colour Module and the Soviet Pentode Colour Module – read more.
Soviet Pentode Colour Module
I took a moment to try them on stems. The Soviet Pentode is amazing!
Perfect to add that tube amp like breakup on a clean guitar track for example.
The Line Driver seemed to be the cleanest of all three.
I definitively need to try the different jumper configurations. Would be interested to have your opinion on this one!
Links:
Brand New, Assembled and Tested.
Every single HRK product is carefully tested with Audio Precision test equipment before the shipping to ensure hassle-free operation.
Shipping
All Items are dispatched from the European Union within 1-3 working days.
We offer Fast & Free Worldwide UPS shipping with tracking.

FREE delivery is available for orders over the 249USD to EU, USA and Canada.
Total cart value / Delivery cost:
up to 99USD / Delivery Cost – 19.99USD
99 – 148USD / Delivery Cost – 14.99USD
149 – 248USD / Delivery Cost – 9.99USD
over 249USD – FREE Delivery
FREE delivery is available for orders over the 299USD to Australia, New Zeland, Japan and other destinations.
Total cart value / Delivery cost:
up to 148USD / Delivery Cost – 19.99USD
149 – 298USD / Delivery Cost – 14.99USD
over 299USD – FREE Delivery
Please check the shipping cost during the checkout.
Delivery to other WorldWide destinations – 24.99USD
VAT and Customs Fees
For non-business orders from the EU, the VAT will be added at the checkout.
VAT is removed automatically for orders from outside the EU.
No Custom Fees for EU Customers.
Orders from the USA below 800USD are customs tax free.
EU Business Customers
If you have the EU VAT number you can purchase the products available in the Bart HRK Shop with no VAT Tax.
Please enter your EU VAT Number at the checkout and the VAT will be deducted from the Total Payment.
The VAT number is automatically checked in the VIES database.
Non-EU Customers
Customers from outside the EU can purchase the items with no VAT.
Please select the destination country and the VAT will be removed automatically.
If the VAT is not removed, please email customer service via the contact form and custom invoice will be issued.
Orders from the USA below 800USD are customs tax-free.
Payment Options:


You can pay for your order with any Credit Card!
Our return policy is a part of the general Terms & Condition which you have to acknowledge at the checkout.
We stand for fair rules and a win-win approach. We understand that our customers may wish to return the product and we do provide such option. However, because we are a small company we can’t afford to run a grade B outlet shop like big distributors and provide the 30 days return period.
We can’t also scrap every returned unit. We could charge our customers more to offset the cost of the returns, this is what major distributors do. Or we can keep our prices low and hope that our customers will appreciate our policy.
This is why we provide the 7 days test period after receiving the package with the ordered items and if you wish to return the item we will accept the return request, providing that the item is not damaged and we can resell the product with the minimal loss for the company.
If the item is damaged during the transport we will do our best to help you and provide the replacement product.