Finally got my hands on a friend's old Ampeg SVT-DI yesterday and I'll get to keep it for a week or three. If you're not familiar with it, it's a tube DI utilizing a 12AU7 (in this case a Groove Tubes) with a rather large output transformer. It's not as big as the transformer in the A-Designs REDDI but it's pretty big. Ampeg discontinued the SVT-DI in the mid-2000's but it still exists as the Khan Vacuum Tube DI, a company I have no relationship with but is run by Obeid Khan, a longtime former Ampeg engineer. A little more streamlined than the SVT-DI but it's the same otherwise. Naturally, I took it right to the gig I had yesterday and tried it, and it sounded absolutely terrific. So I thought I'd make a little audio comparo using the SVT-DI and REDDI, and I threw in the PF-50T just to give some perspective on an actual tube amp as well.
I used my well-modded 76 Precision with EMG Geezer Butler P with a pretty dead set of Dunlop Super Bright nickels. I matched gain levels as close as I could but no other processing was added. For the PF-50T, I used the output transformer XLR out and set the knobs at noon and left the ultra filters off. And look, I made them into MP3's and I don't want to hear any crap about it. They are high quality mono MP3's at 160k bitrate, which translates to 320K if it was stereo, and I used the LAME encoder, so the sound quality is there and it takes up way less space on the TB server. However, if anyone knows a better way to post audio files on a forum these days since Soundcloud won't let you directly link anymore, I'm willing to upload the WAV's to it.
Very interested to hear what others think but I'll tell you what I think...first off, I think the REDDI and the nooned PF-50T sound pretty much the same. Makes sense since the PF-50T has flat response with knobs at noon, and the REDDI is a flat response DI version of a tube amp. The SVT-DI has that tube amp sound as well, but it's a little more subdued in the highs and high mids and maybe has a tad more low end (although I must admit to not being so good about perceiving minor differences in low end response without hearing it in a band context), which coincidentally, is how I usually set my PF-50T when I use it, although I might add a little more bass than that depending on the room...sometimes a lot more...whoa Nellie!
They've each got little things about them that some may prefer over the other but they are all top of the line sound quality with real tube amp sound and feel. I am very fortunate to own two of them, but I will be a little sad to send the SVT-DI back to its owner when the time comes. It's a little different from the REDDI, but I think the sound quality is right up there with it. Still, first world problem.
Oh, and before anyone gets all panty bunched that I'm starting a thread about an Ampeg product, the SVT-DI has been discontinued for years, I know of no plans to bring it or a similar product out in the future, and though you can still get it through Khan Audio, I do not know Mr. Khan or have any sort of relationship with his company. In other words, I did it all for you, you ungrateful unruly mob!
EDIT: Just added a Countryman Type 85 active DI and Whirlwind IMP 2 passive DI to give everyone a sample of what typical active and passive DI's sound like in comparison to the tube DI's.
NEW EDIT: Just added a second SVT-DI file called "P - SVT-DI Boost." This is due to the switch that turns the tube sound on and off in the thru jack adding a fairly hefty gain boost and changing the sound a little. It's a tad brighter to my ears, but sounds really cool as well. You won't hear the gain boost as I tried to match it to the original tracks, but you can hear how the sound has changed.
I used my well-modded 76 Precision with EMG Geezer Butler P with a pretty dead set of Dunlop Super Bright nickels. I matched gain levels as close as I could but no other processing was added. For the PF-50T, I used the output transformer XLR out and set the knobs at noon and left the ultra filters off. And look, I made them into MP3's and I don't want to hear any crap about it. They are high quality mono MP3's at 160k bitrate, which translates to 320K if it was stereo, and I used the LAME encoder, so the sound quality is there and it takes up way less space on the TB server. However, if anyone knows a better way to post audio files on a forum these days since Soundcloud won't let you directly link anymore, I'm willing to upload the WAV's to it.
Very interested to hear what others think but I'll tell you what I think...first off, I think the REDDI and the nooned PF-50T sound pretty much the same. Makes sense since the PF-50T has flat response with knobs at noon, and the REDDI is a flat response DI version of a tube amp. The SVT-DI has that tube amp sound as well, but it's a little more subdued in the highs and high mids and maybe has a tad more low end (although I must admit to not being so good about perceiving minor differences in low end response without hearing it in a band context), which coincidentally, is how I usually set my PF-50T when I use it, although I might add a little more bass than that depending on the room...sometimes a lot more...whoa Nellie!
They've each got little things about them that some may prefer over the other but they are all top of the line sound quality with real tube amp sound and feel. I am very fortunate to own two of them, but I will be a little sad to send the SVT-DI back to its owner when the time comes. It's a little different from the REDDI, but I think the sound quality is right up there with it. Still, first world problem.
Oh, and before anyone gets all panty bunched that I'm starting a thread about an Ampeg product, the SVT-DI has been discontinued for years, I know of no plans to bring it or a similar product out in the future, and though you can still get it through Khan Audio, I do not know Mr. Khan or have any sort of relationship with his company. In other words, I did it all for you, you ungrateful unruly mob!
EDIT: Just added a Countryman Type 85 active DI and Whirlwind IMP 2 passive DI to give everyone a sample of what typical active and passive DI's sound like in comparison to the tube DI's.
NEW EDIT: Just added a second SVT-DI file called "P - SVT-DI Boost." This is due to the switch that turns the tube sound on and off in the thru jack adding a fairly hefty gain boost and changing the sound a little. It's a tad brighter to my ears, but sounds really cool as well. You won't hear the gain boost as I tried to match it to the original tracks, but you can hear how the sound has changed.
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