SV-128BII 15/15W or 24/24W Power AMP from Sunvalley Japan
SV-128BII 15/15W or 24/24W Power AMP from Sunvalley Japan
We are now doing the heat test from Sunvalley. Once it passes the heat test and received approval
by Mr. Ohashi and his technical team, we will start the production process. (
Only assembled 120V is available ( made and assembled by Sunvalley Japan)
KT150
KT170
KT170
Standard tube set (the best version):
"Tung-Sol KT170* 1 pair", "Mullard CV358 / CV5080 / EF37A (NOS) * 4",
"GOLD LION GZ34 / 5AR4 * 1" "VCAP ODAM 1uf * 2 + Audio Note coper 0.047 X 2"
KT150 is so popular now that it can be said to represent current vacuum tubes.
The rating surpasses KT88 in all, and the magnificent plate loss = 70W attractively exists with unparalleled potential.
Historically, the vacuum tube amplifier circuit has advanced, but it cannot be said that the KT150 potential be maximized
with the conventional circuit. A new concept for circuit design is needed to break the established concept of pentode tube = 8W in SET AMP Design.
As a result of careful design and careful sound determination, the SV-128B II has succeeded in drawing out about three times the output of
conventional Single Ended Pentode tube amplifiers.
As for the output section, this unit can select the plate voltage from normal / high. The KT88, 6550 has an output of 15W or more
in the normal mode, while the KT90, KT120, and KT150 has an output of 20W or more in the high regulation mode. This is the output next to the 845
in the transformer drive circuit in the historical SET amplifier of our product. With a B+ voltage of 500V, this performance is almost unparalleled
in the world. Of course, the operation of the output tube is performed within the rating, and the life and sound quality are not sacrificed at all because of the output.
Hashimoto Electric’s custom-made transformers support the powerful output of the SV-128B II. The rectifier tube is the 5AR4, which boasts high efficiency and robustness,
and the front-stage tube is the famous Mullard, which has the nickname of the European version 310A. The CV358 / CV5080 / EF37A (red color) is placed
in the voltage amplification and cathode follower drive, and the output tube is in full swing.
Type: Pentode Tube -SET power amplifier (KT88, 6550, KT90, KT120, KT150 compatible)
This is the permanent solution to get rid of the cell phone interefence of the the driver tubes (EF37A).
This noise shielding is effectively reduce the interference.
Attach files
SV-128BII 15/15W or 24/24W Power AMP from Sunvalley Japan
We are now doing the heat test from Sunvalley. Once it passes the heat test and received approval
by Mr. Ohashi and his technical team, we will start the production process. (
Only assembled 120V is available ( made and assembled by Sunvalley Japan)
KT150
KT170
KT170
Standard tube set (the best version):
"Tung-Sol KT170* 1 pair", "Mullard CV358 / CV5080 / EF37A (NOS) * 4",
"GOLD LION GZ34 / 5AR4 * 1" "VCAP ODAM 1uf * 2 + Audio Note coper 0.047 X 2"
KT150 is so popular now that it can be said to represent current vacuum tubes.
The rating surpasses KT88 in all, and the magnificent plate loss = 70W attractively exists with unparalleled potential.
Historically, the vacuum tube amplifier circuit has advanced, but it cannot be said that the KT150 potential be maximized
with the conventional circuit. A new concept for circuit design is needed to break the established concept of pentode tube = 8W in SET AMP Design.
As a result of careful design and careful sound determination, the SV-128B II has succeeded in drawing out about three times the output of
conventional Single Ended Pentode tube amplifiers.
As for the output section, this unit can select the plate voltage from normal / high. The KT88, 6550 has an output of 15W or more
in the normal mode, while the KT90, KT120, and KT150 has an output of 20W or more in the high regulation mode. This is the output next to the 845
in the transformer drive circuit in the historical SET amplifier of our product. With a B+ voltage of 500V, this performance is almost unparalleled
in the world. Of course, the operation of the output tube is performed within the rating, and the life and sound quality are not sacrificed at all because of the output.
Hashimoto Electric’s custom-made transformers support the powerful output of the SV-128B II. The rectifier tube is the 5AR4, which boasts high efficiency and robustness,
and the front-stage tube is the famous Mullard, which has the nickname of the European version 310A. The CV358 / CV5080 / EF37A (red color) is placed
in the voltage amplification and cathode follower drive, and the output tube is in full swing.
Type: Pentode Tube -SET power amplifier (KT88, 6550, KT90, KT120, KT150 compatible)
- Fixed bias (adjustment required when replacing vacuum tube)
- Input: 1 system No volume
- Wiring specifications: Manual wiring (only heater power supply uses board)
- SP impedance : 4 / 8Ω (16Ω can be selected by changing the wiring)
- Vacuum tube used: CV358 / CV5080 / EF37A x 4, KT150, etc. x 2, 5AR4 x 1
- Output: 20W + 20W or more (when using KT90, KT120, KT150), 15W + 15W or more (when using KT88, 6550)
- Frequency characteristics: 15Hz to 45kHz (1W 8Ω -3dB)
- Gain: 27dB (8Ω)
- Size mm (including protrusions): W400 x D300 x H220
- Weight: 24kg
This is the permanent solution to get rid of the cell phone interefence of the the driver tubes (EF37A).
This noise shielding is effectively reduce the interference.
Attach files
Last edited:
Do you think its quiet enough for dynamic 300 ohm headphones using speaker tap cable ?
This is the SV-128BII for overseas markets . The vacuum tube is Mullard CV358 / EF37A + Tung Sol KT170.
The output is 15W +15W/8Ω (B+400V), or 24W + 24W / 8Ω (B+430V), which is unparalleled in a single beam tube. The code name is "The Hammer".
There are two vesions
B+ 400V 15W
B+ 430V 24W
The coupling capacitor has a voltage amplification stage of Audio Note UK (silver lead)
and a power amplification stage of V-Cap / ODM .
2 X Audio Note Copper
2 X VCAP ODAM 1uf Output cap
The output is 15W +15W/8Ω (B+400V), or 24W + 24W / 8Ω (B+430V), which is unparalleled in a single beam tube. The code name is "The Hammer".
There are two vesions
B+ 400V 15W
B+ 430V 24W
The coupling capacitor has a voltage amplification stage of Audio Note UK (silver lead)
and a power amplification stage of V-Cap / ODM .
2 X Audio Note Copper
2 X VCAP ODAM 1uf Output cap
Last edited:
Sound changes due to heat dissipation
December 13, 2021 Source from Sunvalley forum
My preparation for MUSIC BIRD recording (test data collection) is before this weekend. "KT170 One Game" is scheduled to be recorded at the final OA (12/24 and12/31(repeat)) by the end of this year. We will thoroughly review the Tung Sol KT170, which has been newly introduced (as the top-end of beam power tubes) while listening to it with various amplifiers.
Currently, there are very few manufacturers that state their amplifiers support the KT170, so it will take a considerable amount of time before a mass-produced amplifier with the KT170 standard specifications comes out. In our products- the [URL='https://translate.google.com/website?sl=auto&tl=en&u=https://www.kit-ya.jp/products/detail/940']SV-S1616D (late Dec 2021), SV-P1616D , SV-128BII (April2022) , SV-8800SE have completed the compatibility experiment. For products in stock as soon as possible, we will add the KT170 tube specification as the most powerful version to the lineup- and we will start selling it separately, so please look forward to this new tube option.
For example, when you think about using the KT170 for the SV-S1616D, you may be worried that the amplifier will become too hot and fail. For example, there is a vacuum tube such as 845 whose plate surface rises to more than 200 degrees, so the image is certainly that "large glass tube envelope = high temperature".
Let's actually measure it.
First, try inserting the Svetlana EL34 into the S1616D. It's one of the most familiar tubes. Just one hour after the power is turned on, if you measure the plate center temperature with a non-contact infrared thermometer, you can see that it is in the range of 175 ° C to 180 ° C.
And this is the KT170. The image is hard to see, but if you measure the temperature after 1 hour in the same way, you can see that it is in the range of 105 ° C to 110 ° C. Surprisingly, the temperature of KT170 is about 70 ℃ lower.
If you think about it, you may think that when driving on the highway at 100km / h, which one has the heavier engine load, a light car or a large saloon? In other words, which one will increase the number of revolutions? The above picture shows that EL34 (plate loss 25W) and KT180 (plate loss 85W) have completely different margins. It may be easier to compare the plate loss to the engine displacement.
[URL='https://translate.google.com/website?sl=auto&tl=en&u=https://www.tec-sol.com/hs_data/Image/brand/tnsl_kt170.pdf']KT150 and KT170 are very similar in terms of electrode structure and electrical characteristics from the specifications of KT170 and the characteristic comparison when installed in the amplifier. As a result of verification over two weeks, it is judged that the KT170 is an output tube that has acquired even higher plate loss due to its physical shape (glass size) and improved heat dissipation.
However, the sound is quite different between KT150 and KT170. Obviously, the KT170 is clearer and cleaner, and there is no sense of distortion at high output ... I'm hoping to convey the true value and features of this area in this week's recording.
SV-128Bll --> https://www.diyaudio.com/community/threads/sunvalley-sv-128bll.379390/
SV-1616D ---> https://www.diyaudio.com/community/threads/sunvalley-sv-s1616d-300b.371736/
Please stay tuned
December 13, 2021 Source from Sunvalley forum
My preparation for MUSIC BIRD recording (test data collection) is before this weekend. "KT170 One Game" is scheduled to be recorded at the final OA (12/24 and12/31(repeat)) by the end of this year. We will thoroughly review the Tung Sol KT170, which has been newly introduced (as the top-end of beam power tubes) while listening to it with various amplifiers.
Currently, there are very few manufacturers that state their amplifiers support the KT170, so it will take a considerable amount of time before a mass-produced amplifier with the KT170 standard specifications comes out. In our products- the [URL='https://translate.google.com/website?sl=auto&tl=en&u=https://www.kit-ya.jp/products/detail/940']SV-S1616D (late Dec 2021), SV-P1616D , SV-128BII (April2022) , SV-8800SE have completed the compatibility experiment. For products in stock as soon as possible, we will add the KT170 tube specification as the most powerful version to the lineup- and we will start selling it separately, so please look forward to this new tube option.
For example, when you think about using the KT170 for the SV-S1616D, you may be worried that the amplifier will become too hot and fail. For example, there is a vacuum tube such as 845 whose plate surface rises to more than 200 degrees, so the image is certainly that "large glass tube envelope = high temperature".
Let's actually measure it.
First, try inserting the Svetlana EL34 into the S1616D. It's one of the most familiar tubes. Just one hour after the power is turned on, if you measure the plate center temperature with a non-contact infrared thermometer, you can see that it is in the range of 175 ° C to 180 ° C.
And this is the KT170. The image is hard to see, but if you measure the temperature after 1 hour in the same way, you can see that it is in the range of 105 ° C to 110 ° C. Surprisingly, the temperature of KT170 is about 70 ℃ lower.
If you think about it, you may think that when driving on the highway at 100km / h, which one has the heavier engine load, a light car or a large saloon? In other words, which one will increase the number of revolutions? The above picture shows that EL34 (plate loss 25W) and KT180 (plate loss 85W) have completely different margins. It may be easier to compare the plate loss to the engine displacement.
[URL='https://translate.google.com/website?sl=auto&tl=en&u=https://www.tec-sol.com/hs_data/Image/brand/tnsl_kt170.pdf']KT150 and KT170 are very similar in terms of electrode structure and electrical characteristics from the specifications of KT170 and the characteristic comparison when installed in the amplifier. As a result of verification over two weeks, it is judged that the KT170 is an output tube that has acquired even higher plate loss due to its physical shape (glass size) and improved heat dissipation.
However, the sound is quite different between KT150 and KT170. Obviously, the KT170 is clearer and cleaner, and there is no sense of distortion at high output ... I'm hoping to convey the true value and features of this area in this week's recording.
SV-128Bll --> https://www.diyaudio.com/community/threads/sunvalley-sv-128bll.379390/
SV-1616D ---> https://www.diyaudio.com/community/threads/sunvalley-sv-s1616d-300b.371736/
Please stay tuned
Victor, interesting temp reading of the KT 170, can you show us a temperature reading of the 300B for the sake of comparison?Sound changes due to heat dissipation
December 13, 2021 Source from Sunvalley forum
My preparation for MUSIC BIRD recording (test data collection) is before this weekend. "KT170 One Game" is scheduled to be recorded at the final OA (12/24 and12/31(repeat)) by the end of this year. We will thoroughly review the Tung Sol KT170, which has been newly introduced (as the top-end of beam power tubes) while listening to it with various amplifiers.
Currently, there are very few manufacturers that state their amplifiers support the KT170, so it will take a considerable amount of time before a mass-produced amplifier with the KT170 standard specifications comes out. In our products- the [URL='https://translate.google.com/website?sl=auto&tl=en&u=https://www.kit-ya.jp/products/detail/940']SV-S1616D (late Dec 2021), SV-P1616D , SV-128BII (April2022) , SV-8800SE have completed the compatibility experiment. For products in stock as soon as possible, we will add the KT170 tube specification as the most powerful version to the lineup- and we will start selling it separately, so please look forward to this new tube option.
For example, when you think about using the KT170 for the SV-S1616D, you may be worried that the amplifier will become too hot and fail. For example, there is a vacuum tube such as 845 whose plate surface rises to more than 200 degrees, so the image is certainly that "large glass tube envelope = high temperature".
Let's actually measure it.
First, try inserting the Svetlana EL34 into the S1616D. It's one of the most familiar tubes. Just one hour after the power is turned on, if you measure the plate center temperature with a non-contact infrared thermometer, you can see that it is in the range of 175 ° C to 180 ° C.
And this is the KT170. The image is hard to see, but if you measure the temperature after 1 hour in the same way, you can see that it is in the range of 105 ° C to 110 ° C. Surprisingly, the temperature of KT170 is about 70 ℃ lower.
If you think about it, you may think that when driving on the highway at 100km / h, which one has the heavier engine load, a light car or a large saloon? In other words, which one will increase the number of revolutions? The above picture shows that EL34 (plate loss 25W) and KT180 (plate loss 85W) have completely different margins. It may be easier to compare the plate loss to the engine displacement.
[URL='https://translate.google.com/website?sl=auto&tl=en&u=https://www.tec-sol.com/hs_data/Image/brand/tnsl_kt170.pdf']KT150 and KT170 are very similar in terms of electrode structure and electrical characteristics from the specifications of KT170 and the characteristic comparison when installed in the amplifier. As a result of verification over two weeks, it is judged that the KT170 is an output tube that has acquired even higher plate loss due to its physical shape (glass size) and improved heat dissipation.
However, the sound is quite different between KT150 and KT170. Obviously, the KT170 is clearer and cleaner, and there is no sense of distortion at high output ... I'm hoping to convey the true value and features of this area in this week's recording.
SV-128Bll --> https://www.diyaudio.com/community/threads/sunvalley-sv-128bll.379390/
SV-1616D ---> https://www.diyaudio.com/community/threads/sunvalley-sv-s1616d-300b.371736/
Please stay tuned