|
Post by Stylemaster on Sept 13, 2007 14:36:30 GMT -7
Can somebody explain it in more depth as to what it sounds like?
I'm trying to decide between buying a NOS JAN Philips/Sylvania 5AR4 (mislabeled 5V4GA) or a relabeled Mullard (more than 2X the $) from KCA. The Philips/Sylvania is supposed to have more sag than the Mullard.
|
|
|
Post by billyguitar on Sept 13, 2007 15:30:38 GMT -7
The most obvious way to hear sag is in a cathode biased amp. Just for the most effect you could put a 5Y3 in an amp that normally takes a 5AR4 or 5U4. Turn it way up. Use your bridge pickup and hit a power chord real hard. Then you'll hear the volume swell up after the chord.
|
|
|
Post by tjstrat on Sept 13, 2007 15:34:18 GMT -7
Some of Neil Young's recent electric albums are full of it... Also, the HBE Power Screamer has a toggle that gives you this massive sag. Great stuff.
|
|
|
Post by billyguitar on Sept 13, 2007 19:23:54 GMT -7
I forgot to say that sag is really compression. Neal Young's Tweed Deluxe does sag and bloom a lot. I've got three old tweed Deluxes and that's part of the sound. I have a tweed Tremolux too which is almost the same circuit. They are fixed bias so they are a little louder but very little sag.
|
|
|
Post by billyguitar on Sept 13, 2007 19:27:32 GMT -7
I have played around with different rectifiers in my cathode biased Zs, Stang Ray and Maz 38. These amps don't really sag much, at normal volumes, no matter which rectifier I tried. The 5U4 just made the Ray sound slower. The 5V4 just made it a little quieter. Oddly enough the Route 66 does it the most. Actually not so much sag as bloom after the note is played.
|
|
|
Post by John on Sept 14, 2007 6:42:52 GMT -7
What does it sound like? Actually, it's more of a feel than something you hear.
The SAG comes from the inability of your amp to quickly process a big powerful note or chord when the amp is turned up high in volume. Under these conditions, that requires a lot of power very quickly. A tube rec doesn't do a very good job at processing this immediate power need. It takes a few milliseconds to catch up and properly process the power needs. These few milliseconds are referred to as the SAG. Instead of properly processing the needed power (like a solid state rec can), there is sort of a softer attack (sort of like compression) because the amp can't keep up. This all happens in the blink of an eye. (actually about 10 can fit into the blink of an eye...it's that fast) So you don't really hear it in terms of tone, but you feel it. Many people think it makes for a more responsive/dynamic/spongy amp. Where solid state rec amps are thought of as a bit more aggressive. It's why we love our tube rec 59' Fender bassman with it's spongy softer feel and why we love our solid state rec Marshall plexi's with their aggressive hard rock feel...even though they're VERY much the same amp inside. (I'm REALLY generalizing here)
Given that: That's not to say that a tube rec is better than a solid state. They're just different. It's what you want to hear combined with the type of music you're playing.
|
|
|
Post by Phil (aka Phil) on Sept 14, 2007 7:01:57 GMT -7
I have played around with different rectifiers in my cathode biased Zs, Stang Ray and Maz 38. These amps don't really sag much, at normal volumes, no matter which rectifier I tried. The 5U4 just made the Ray sound slower. The 5V4 just made it a little quieter. Oddly enough the Route 66 does it the most. Actually not so much sag as bloom after the note is played. The "feel" of am amp is also heavily influenced by the amount and style of power supply filtering. That's one of the reasons that the Z28, Route 66, KT45 and Delta 88 are so different.... they have different amounts of filtering in addition to having different output tubes and trannies. The 66 (at least my 66, a very early one) is somewhat "under filtered"- when done correctly this gives a great broken-in feel, not too stiff, just enough compression. That's also where the "overtones" come from. The Doc is a master of this. Some of the newer amps like the Marshall Bluesbreaker RI's have too much filtering, IMO, making the amp feel stiff. Phil
|
|
|
Post by Stylemaster on Sept 14, 2007 8:50:31 GMT -7
What does it sound like? Actually, it's more of a feel than something you hear. The SAG comes from the inability of your amp to quickly process a big powerful note or chord when the amp is turned up high in volume. Under these conditions, that requires a lot of power very quickly. A tube rec doesn't do a very good job at processing this immediate power need. It takes a few milliseconds to catch up and properly process the power needs. These few milliseconds are referred to as the SAG. Instead of properly processing the needed power (like a solid state rec can), there is sort of a softer attack (sort of like compression) because the amp can't keep up. This all happens in the blink of an eye. (actually about 10 can fit into the blink of an eye...it's that fast) So you don't really hear it in terms of tone, but you feel it. Many people think it makes for a more responsive/dynamic/spongy amp. Where solid state rec amps are thought of as a bit more aggressive. It's why we love our tube rec 59' Fender bassman with it's spongy softer feel and why we love our solid state rec Marshall plexi's with their aggressive hard rock feel...even though they're VERY much the same amp inside. (I'm REALLY generalizing here) Given that: That's not to say that a tube rec is better than a solid state. They're just different. It's what you want to hear combined with the type of music you're playing. Wow. Thank you. Best explanation (or the one easiest for me to understand). I remember loving the softer, more forgiving feel/attack and delayed, beautiful bloom of the new Fender Tweeds when I was amp shopping a year ago and not liking the instant thud attack of some of the non-Fender tube amps I tried. But my tastes have changed since then because, for me, the tweed sound wasn't as versatile. I wanted an amp I could play clean, bright James Brown soul-scratch rhythm with and also coax an overdriven and Black-Face-clean-on-the-verge-of-clipping blues solo out of. I found that listening to Buddy Whittington's MAZ clips and now I have a MAZ Sr and am very happy with it. If I could afford a tweed (thinking Victoria) I'd have that softer bloom sound as well.
|
|
|
Post by Stylemaster on Sept 14, 2007 9:02:32 GMT -7
I have played around with different rectifiers in my cathode biased Zs, Stang Ray and Maz 38. These amps don't really sag much, at normal volumes, no matter which rectifier I tried. The 5U4 just made the Ray sound slower. The 5V4 just made it a little quieter. Oddly enough the Route 66 does it the most. Actually not so much sag as bloom after the note is played. I am responding to your quote, "...Stang Ray and Maz 38. These amps don't really sag much, at normal volumes, no matter which rectifier I tried."Heres what it says on www.aikenamps.com/Sag.html about SAG, or lack thereof, on class A tube amps: "Note that sag effectively only occurs in class AB amplifier output stages. A true class A amplifier has no sag because the current draw at full power is the same as the current draw at idle."Isn't the MAZ a class A amp?
|
|
|
Post by dixiechicken on Sept 15, 2007 4:26:41 GMT -7
No the Maz 38 Sr is cathode biased a class AB amp.
A single ended amp with one EL84 ( single ended == class A ) can generate about 6 watts of power. ( from Mullard specs on their EL84 )
A "four tubed parallell single ended" amp would generate about 24 watts of power. The MAZ Sr is formally rated at 38 watts of power.
Cheers: Dixiechicken
|
|