I am mentioning this because some amps like the FiiO E9, for example, react differently to headphones with different impedances. What I mean by this is that the frequencies that I feel that are boosted or recessed in the amps sound signature are the same whether I use them with the Grado SR225i or the Sennheiser HD600. Using both the Grados and the Senns, these two amps affect the headphones in the same ways. Dimension 79mm (D) X 79mm (W) X 44mm (H).Frequency response 10Hz-60KHz +/- 0.25dB.Powerful, dynamic, and sweet TUBE sound.

In case the specs matters to some of you readers, here are the details straight from the manufacturer’s website: V1 Deluxe Features

I will also talk about how the Bravo compares with other amps that I have with me at the moment including the FiiO E10, FiiO E9, a DIY OTL Tube amp (codename: Kraken) with a similar design as a Bottlehead Crack/ Woo Audio 3. I might comment later on also about the changes in their sound if ever I get to do any tube rolling or modifications. In this review, I will be talking about the sound of the Bravo amps as they sound in their stock configurations driving the 32 ohm Grado 225i and the 300 ohm Sennheiser HD600s. I don’t think the tubes can be swapped between the two amps without doing any modifications. I think the difference in the caps makes The V1 be able to work with the Electro Harmonix 6922 and the Shu Guang 12AU7 tube with the V2. These amps seem to be very similar in design looking almost identical to one another except for the difference in two caps at the front portion of the amp. Since just a few days ago, I have been listening to not just one but two variations of the Bravo amps namely the V1 and the V2. I am always on the lookout for good sounding budget-friendly amps and the Bravo Amps have been on my sites for a few months now.

Bravo tt radio sound board