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Tech 21 VT Bass 1969 head!

#341
tech21nyc said:
Our tech here also fixes amps and he has worked on a number of SVT's over the years. He said he hasn't seen one yet that puts out 300 watts rms. This is not saying the difference between the amps is all that great. 285 or 345 watts as you can see by the decimal meter is not a huge jump. The thing is we don't really know offhand how Ampeg arrived at that spec all those years ago. 300 watts at what %THD. .05%,1%,5%? Does anyone have an old Ampeg SVT manual?
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Bass Gear Magazine recently tested a 1974 SVT and reported 328 W at 4% THD (issue #4, p. 56).
 
#344
my two SVT head put out 310 and 314 watts before any clipping the last time i measured them, taken with my accu-bias meter with it's wattage probe which won't measure ouput with distortion.

with my fluke, it measured alot more with 5% distortion.

to me, the VT 1969 sounds great in the clip, but neither amp sounds like it's running very loud (or at least at the volume that i run mine when playing live).
 
#345
johnk_10 said:
my two SVT head put out 310 and 314 watts before any clipping the last time i measured them, taken with my accu-bias meter with it's wattage probe which won't measure ouput with distortion.

with my fluke, it measured alot more with 5% distortion.

to me, the VT 1969 sounds great in the clip, but neither amp sounds like it's running very loud (or at least at the volume that i run mine when playing live).
Click to expand...

I was just about to bring that up. Neither amp seems loud at all, and neither really sounds that full, thick, or ballsy either. Of course, terminology like that can mean vastly different things to different players, but I think most people here who play an SVT will agree that the SVT in this example doesn't sound even remotely pushed as far as it can go and stay 'clean' sounding.
 
#346
Both amps were set just to the point of clipping and set flat for comparison purposes. The measurements were done with a signal generator, 1000 watt static non-inductive dummy load and oscilloscope. We didn't monitor our line voltage but both amps were plugged into the same circuit. The Ampeg's 285 watt rating is well within it's specification.

In an article from Vintage Guitar Magazine with amp guru Ken Fischer (Ampeg & Tranwreck amps) Kenny states that Ampeg originally made SVT's with 6146 tubes for an output of 330 watts. He states when they changed to 6550 tubes the output dropped to 240 watts even though the amp was still rated at 330 watts. Here is the link to the article. http://books.google.com/books?id=kxtcysXZwRUC&pg=PA128&lpg=PA128&dq=%22The+first+amps+used+six+6146+tubes.%22&source=bl&ots=FqDkSIXUtz&sig=T2BXeuTUGuMumZJhiG9R3iPWGNo&hl=en&ei=0cpKTe7zDYOglAeAlMGgBQ&sa=X&oi=book_result&ct=result&resnum=1&ved=0CB8Q6AEwAA#v=onepage&q=%22The%20first%20amps%20used%20six%206146%20tubes.%22&f=false

If the amps didn't sound LOUD to you in the video it's because they were set clean and to their maximum output "before" clipping.That's what the RMS rating is.Also the microphone was positioned at 1 meter away because that is how SPL measurements are taken. This was for testing purposes. We will be posting another video with the amps being over driven soon.Hearing a close mic'd bass amp through a YouTube video clip can't duplicate standing in front of a 410 & 115 cab at 110dB.
 
#348
The was one other thing that I saw form the video, the second channel on the ampeg: the volume was set to 10 or 11 o'clock, while the "levels" on the tech21 were maxed out...

What gives? Am i missing something? A higher level on the ampeg is where some of that good sound comes from ;)
 
#349
andrew said:
Why did you not use the SVT's first channel with the mid control for the test?
Click to expand...

Because we wanted to set both amps as flat as possible to do a direct comparison. Since our goal was to show how loud both amps could be pushed "before" clipping even if we used the other channel we would still have to reduce the gain of the amp to keep it in it's un-clipped operating range.


And I notice the 1969's master volumes are turned all the way up, is it ok to run it that way all the time?
Click to expand...

Of course. The SVT has no master volume control so we had to set our amp in the same manner. If you want maximum clean headroom you just turn the master all the way up. The advantage our VT Bass head has over the SVT is that if you like the sound of the actual SVT with the volume at say 3 o'clock and you are playing in an environment that won't allow that much volume or you don't have enough speakers to handle the power you can turn up our amp and reduce the master. That way your over driven tone is no longer volume dependent. While we have associated this type of master volume scheme with guitar amplification for a number of years it also works very well for bass players as well. The other advantage to running your preamp gain a little higher and lowering your master volume is that your sound will usually be more full sounding and less spiky than running your amp super clean. Of course your style, technique and the type of music you are playing will all come into play. The rock guy will want a crunchier tone and the jazz guy may want a pristine tone. Hence the option.
 
#350
tech21nyc said:
If you want maximum clean headroom you just turn the master all the way up. The rock guy will want a crunchier tone
Click to expand...

I really hope the VT Bass preamp interacts differently with the power section than the Bassdrive and Paradrive pre's in the Landmark 300 do, because my experience with the LM 300 is it did not sound happy or very good running the master volumes maxed and controlling the volume with the drive controls nearing noon on the drive knob. I really want to believe the 1969 is loud enough for my needs but my previous experience with the LM300 can't shake my feeling it just won't be. I'm sure it'll work great for some guys though.

To me this video demonstration seems like you're saying a mini van is as fast as a racecar because they can both do 70 mph.
 
#351
tech21nyc said:
Both amps were set just to the point of clipping and set flat for comparison purposes. The measurements were done with a signal generator, 1000 watt static non-inductive dummy load and oscilloscope. We didn't monitor our line voltage but both amps were plugged into the same circuit. The Ampeg's 285 watt rating is well within it's specification.

In an article from Vintage Guitar Magazine with amp guru Ken Fischer (Ampeg & Tranwreck amps) Kenny states that Ampeg originally made SVT's with 6146 tubes for an output of 330 watts. He states when they changed to 6550 tubes the output dropped to 240 watts even though the amp was still rated at 330 watts. Here is the link to the article. http://books.google.com/books?id=kx..."The first amps used six 6146 tubes."&f=false

If the amps didn't sound LOUD to you in the video it's because they were set clean and to their maximum output "before" clipping.That's what the RMS rating is.Also the microphone was positioned at 1 meter away because that is how SPL measurements are taken. This was for testing purposes. We will be posting another video with the amps being over driven soon.Hearing a close mic'd bass amp through a YouTube video clip can't duplicate standing in front of a 410 & 115 cab at 110dB.
Click to expand...


Hey can you do a blind test?
Put up a black screen between the player and amps, Set the tone controls using an RA so both amp curves match. and then let many players A/B and see if they can tell any difference?
 
#352
seamonkey said:
Hey can you do a blind test?
Put up a black screen between the player and amps, Set the tone controls using an RA so both amp curves match. and then let many players A/B and see if they can tell any difference?
Click to expand...

The tones in the video were pretty close to each other.
 
#353
andrew said:
The tones in the video were pretty close to each other.
Click to expand...

They really were, but even so I think I preferred the VT's tone just a hair more.

Anyways, I think I've made my peace enough with this head. I don't think I'll ever understand why Tech21 is releasing the amp in its current form - and that's okay. I'll just have to wait until I have one of these heads in my possession to see whether or not it lives up to my current expectations or exceeds them.

And for what it's worth, I'd LOVE for this amp to be able to replace my SVT, but as of now I still don't see it happening.
 
#356
jmattbassplaya said:
They really were, but even so I think I preferred the VT's tone just a hair more.
Click to expand...
i think i know why...i once compared my 69 svt with the markbass lmii (which is a near-flat amp when nooned). the 2nd channel is a bright channel with a low cut. the lows can be dialed back in easily enough, though. and that would also explain why the top end sounded so similar to the vt amp nooned. the treble knob bites pretty good when the pedal is nooned. tomorrow i plan to do this test for myself. probably won't record it, though.

btw, my svt has 6146b's...i have no idea what it benches at, but my tech said he definitely thought it had a little more power than other svt's with 6550's.
 
#357
CharlieC said:
Here's my business plan worth 2 cents:

Take the VT Deluxe, the majorly upgraded VT Bass, with 3 programmable channels + XLR out

Couple it with a now common-place, Class D engine ala Crown XLS1000 or Peavey IPR 1600 (~1000 watts @ 4-ohms)

Now add the following mods that other 3rd-parties continue to successfully impart on existing VT pedals:

1. the infamous "Blend" knob
2. speaker sim defeat switch

Now fix the legacy issues carried forward from the Landmark 300 design

1. provide a front panel "Mute" switch (so that use of a footswitch is now optional)
2. provide industry-standard Speakon outs

Street price = $849

Weight = 10-pounds

Target Market = everyone who bought the previous pedals + new customers

See you at NAMM 2012 in the "Don't Hold Your Breath" booth :-)

Sure, it could be a flop, what do I know?
Click to expand...

CharlieC said:
... continued

Product Name = VT Legend

So I will offer the VT Bass, VT Deluxe + now the VT Legend head (like Landmark, but not.)

Or if I wanted to play-off the "rocket-engine" marketing line, maybe call it the VT RockHead.

Worst case scenario:

The apparent trend now in bass amplification is the use of Class D.

If for whatever technological, philosophical or financial reason I cannot market with Class D then I will not recycle an older, outdated design from a past product. And if pressed to recycle, I would at least make an attempt to address any shortcomings it could now be regarded as having in 2011.

So let me avoid the risk, expense, and aggravation altogether now and simply produce a rack-mountable preamp-only unit, with all the same bells + whistles as spec'd above. This product would pair well with any of the 3rd-party Class D amps readily available, and at the same time it would simply be the next progression in the product line.

Product Name = VT Premier

Best of all, I know of a place called TalkBass where I could gain all the market research I would need for the best chance success, for free, one-on-one with my current + future customers. :D

Again, this is all my 2 cents, what do I know?

Thanks for allowing me to indulge.
Click to expand...

Just having some fun with Photoshop today...

Could I interest anyone in one of these? :hyper:

vt_premier.jpg

Cheers!
 

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