Translated from Mr Ohashi's Sun Valley forum
For example, let's assume that you have a single tube amp that you like. If you are thinking in your mind, ``How much better would it be if the output was a little louder with this sound quality...” What would you do?
The simplest countermeasure, which does not require modification and is also reversible (can be restored if necessary), is to prepare another identical amplifier and make it 2 parallel single MONOs. It's a target.
Basically, by branching the input and inputting it to both the L and R channels in parallel, shorting the + side of the output transformer and taking out the output, you can transform it into a para-single with twice the theoretical output. You can. I tried to draw a conceptual diagram.
It may seem complicated when you draw it like this, but you can do it by preparing very simple attachments (branch plug and short RCA cable x 2 each).
The important point to remember is that the L and R gains of the amplifier are the same. Otherwise, it may not be possible to synthesize ideal signals. Therefore, it is desirable that the second amplifier has similar characteristics to the first. In terms of sound quality, it would be best to have the same configuration for both vacuum tubes if possible. The SV-284D balanced single is basically the same idea.
It's difficult to do right now, but I'd like to introduce an example of how two SV-91Bs or SV-S1616Ds were assembled with the same specifications at the same time, so please look forward to future reports. The SV-501SE may also be suitable.
For example, let's assume that you have a single tube amp that you like. If you are thinking in your mind, ``How much better would it be if the output was a little louder with this sound quality...” What would you do?
The simplest countermeasure, which does not require modification and is also reversible (can be restored if necessary), is to prepare another identical amplifier and make it 2 parallel single MONOs. It's a target.
Basically, by branching the input and inputting it to both the L and R channels in parallel, shorting the + side of the output transformer and taking out the output, you can transform it into a para-single with twice the theoretical output. You can. I tried to draw a conceptual diagram.
It may seem complicated when you draw it like this, but you can do it by preparing very simple attachments (branch plug and short RCA cable x 2 each).
The important point to remember is that the L and R gains of the amplifier are the same. Otherwise, it may not be possible to synthesize ideal signals. Therefore, it is desirable that the second amplifier has similar characteristics to the first. In terms of sound quality, it would be best to have the same configuration for both vacuum tubes if possible. The SV-284D balanced single is basically the same idea.
It's difficult to do right now, but I'd like to introduce an example of how two SV-91Bs or SV-S1616Ds were assembled with the same specifications at the same time, so please look forward to future reports. The SV-501SE may also be suitable.
It may work with SET amps with low damping factor, but never try it with solid state amps or any amp with low output impedance.
Even in that case you get double power only if you connect the speaker to OPT taps for double speaker impedance, because the current flowing through the speaker is shared between the amps. It is not an issue with 4 Ohm speakers but most tube amps do not have dedicated output for 15 Ohms.
Even in that case you get double power only if you connect the speaker to OPT taps for double speaker impedance, because the current flowing through the speaker is shared between the amps. It is not an issue with 4 Ohm speakers but most tube amps do not have dedicated output for 15 Ohms.
You could try in inverting 0.97 gain chipamp.
Lm1875 must be set gain of 10 to be stable.
Feed in (+) from amp output. Ground (-).
If R fb = 20k connect 21k resistor to Inverting pin of LM1875, other end to tube amp (+) pin.
Connect speaker across (+) tube amp and output from LM1875 (-) .
Tube amp should use 4 ohm tap as it is now bridged.
Lm1875 must be set gain of 10 to be stable.
Feed in (+) from amp output. Ground (-).
If R fb = 20k connect 21k resistor to Inverting pin of LM1875, other end to tube amp (+) pin.
Connect speaker across (+) tube amp and output from LM1875 (-) .
Tube amp should use 4 ohm tap as it is now bridged.