Solid state/class d vs tube amps

[murdockbass]

So, back to the HELL that tube amps are...

The trade offs are obvious, BUT....

It is better to RULE in HELL, than to serve in light weight, spongy tone and fits in my pocket heaven!

Remember folks...

Roadies LOVE Ampeg!

 

[Eddie LeBlanc]

I have been into the audiophile audio stuff along with being a bassist and musician for over 50 years. Tubes are fantastic, but need proper biasing, and matching to sound superb. No tube can last 10 years without some degradation, no matter what anyone says, period. An audiophile Tube amp (one for audio reproduction, not just playing a bass through) usually requires tube change outs somewhat frequently. And Re-Biasing of each tube (whether manual or self biasing circuits) in it's output stage. Believe me I know, Conrad Johnson, Audio Research, McIntosh, even Dynaco Modified equip.

I used to even have a studio rack mount modified Dynaco amp a Mark VI amp as a Bass Power Amp using several different Preamps, (including a Demeter HBP1). All a real killer sound, but a pain to carry around and also maintain. Replacement Tube sets (in matched pairs, quads, or sextets) are now very expensive. And sometimes harder to obtain. Especially Mil Spec numbers like the 8417s in the Dyna. Plus the cost to manufacture has risen dramatically. After all, higher voltages on tube circuits (300 to 500 volts), make prices go up. So the higher quality components like Caps and Resistors are more expensive. Especially the high voltage Polyester and metal films that are audiophile quality verses stand industry components, are harder to get.

Enter Mos-Fets and also Class D equipment. They too have better performance than the old bi-polar transistors. And in fact distort in the same way a tube runs in triode operation. Only allowing even order harmonics during distortion. (Older Bi-Polars allow odd order harmonics). Plus there is an advantage of lower operating voltages that allows for higher quality components at a more affordable cost structure. In fact a tube front end and class D output is quite affordable, and can have extremely high quality sound reproduction. But the entire solid state amps, do well because they now use Mos-Fet frontends.

Then there is the addition of size, weight, and current draw. I used to worry about current draw in some location, starving the tubes for power. Now no problem, Class D Genzler 800 (or even the Crown XLS 1500) pulls hardly any AC current. It is all light weight, so I don't need a crew to move my stuff, and the footprint is minimal. Plus they can put out transients easily due to the extremely higher wattage capability.

And I no longer get my old tube tester out checking tubes and trying to match them.

Bass players need 10 times the output compared to guitarists, in order to compensate for the transients and perceived volume levels. So your guitar player may have a 30 watt Tube amp (somewhat easier to deal with and construct), while you may need 300 watts or more. In a tube amp, that is much more to afford and deal with, just saying.

 

[Drgonzonm]

Not a long as some people think? For sure
I think there are a lot of tubes out there that measure less than 75% of their original spec. They still work, but they aren't up to what they once were. Just changing them people notice a difference.

Using a worn out tube doesn't effect the rest of the amp. In fact I'd say some tubes come off the manufacturer line at less than 75% spec these days but end up in circulation anyhow.

I've read Eniac had 18,000 tubes and the longest it ran without failure is 5 days. On average it crashed every other day from a tube failure.

When I was taking a summer class in programming assembler, the main frame, would be be down during the day, so we had to run programs at night on Hollerith cards. I believe that IBM 370 had 32 or 64k memory. Rumor was the AC was designed for sea level and the computer lived at a mile high. I'm just glad we didn't have to program on the 1620.

You can back calculate from the MTBF formula what the expected tube tube life was. I'm too lazy to look up the formula and crunch the numbers. I would expect the average life of a tube to be a minimum of 5000 hours.

Who runs guitar amps with tubes at design center values?

 

[Blue]

As a "older gentlemen", I've come to appreciate gravity. My solution? a custom Tube Preamp - think Fender Showman front end, but with a Big Tube 6SL7 (really a 5691) - and an 11 pound "1800 watt" QSC pushing the speakers.

 

[Pete Greaves]

Tubes wear out. They do not last forever.

True, but I owned a WEM 30 watt bass head (sixties), and did not change a single tube for 15 years. They don't last forever, but if you are constantly changing them you have an issue with your amp.

 

[tubestuff]

Nokia phones....

Power tube wear out pretty fast..they can last a couple of years if used at home..but if used regularly at venues, they last about a year...

Drove my V4 a minimum of around 8 hrs a week for about 5 year, many times at FULL volume, never changed a tube.
Granted it was an Ampeg I purchased used, and had tubes Made in USA but never a problem. Chinese power tubes, many, can't take a lot of abuse. YMMV.

 

[JimmyM]

Bass players need 10 times the output compared to guitarists, in order to compensate for the transients and perceived volume levels. So your guitar player may have a 30 watt Tube amp (somewhat easier to deal with and construct), while you may need 300 watts or more. In a tube amp, that is much more to afford and deal with, just saying.

This is all assuming that your guitarist with the 30w amp is turning it up all the way. Pretty much none of the guitarists I've ever worked with have done that. I'm trying to think of one who did and I can't think of a one.

 

[Drgonzonm]

Bass players need 10 times the output compared to guitarists, in order to compensate for the transients and perceived volume levels. So your guitar player may have a 30 watt Tube amp (somewhat easier to deal with and construct), while you may need 300 watts or more. In a tube amp, that is much more to afford and deal with, just saying.

You are right, but 300 watts is only twice as loud, just enough to address our natural hearing loss as frequency drops.
Some of those old audiophile amps, would oscillate, if the tubes were not properly bias or if an inferior quality of tubes were used.
When the standard is less than 1% distortion, you have a lot of maintenance work. When distortion can be 5% or higher like many guitar tube amps, less maintenance is required.
Not all of us are willing to spend $2400 for a pair of 80w triode tubes we are going to run in class A on a SE amp. For the price of the output transformer, we can now buy an ss amp that idles at 80w.
Long live the UL transformer.

 

[GreyEagle]

Because your first language isn't English?

Or because they chose the name from a Music Man Bongo bass guitar? Hmmmm?

 

[agedhorse]

I have been into the audiophile audio stuff along with being a bassist and musician for over 50 years. Tubes are fantastic, but need proper biasing, and matching to sound superb. No tube can last 10 years without some degradation, no matter what anyone says, period. An audiophile Tube amp (one for audio reproduction, not just playing a bass through) usually requires tube change outs somewhat frequently. And Re-Biasing of each tube (whether manual or self biasing circuits) in it's output stage. Believe me I know, Conrad Johnson, Audio Research, McIntosh, even Dynaco Modified equip.

I used to even have a studio rack mount modified Dynaco amp a Mark VI amp as a Bass Power Amp using several different Preamps, (including a Demeter HBP1). All a real killer sound, but a pain to carry around and also maintain. Replacement Tube sets (in matched pairs, quads, or sextets) are now very expensive. And sometimes harder to obtain. Especially Mil Spec numbers like the 8417s in the Dyna. Plus the cost to manufacture has risen dramatically. After all, higher voltages on tube circuits (300 to 500 volts), make prices go up. So the higher quality components like Caps and Resistors are more expensive. Especially the high voltage Polyester and metal films that are audiophile quality verses stand industry components, are harder to get.

Enter Mos-Fets and also Class D equipment. They too have better performance than the old bi-polar transistors. And in fact distort in the same way a tube runs in triode operation. Only allowing even order harmonics during distortion. (Older Bi-Polars allow odd order harmonics). Plus there is an advantage of lower operating voltages that allows for higher quality components at a more affordable cost structure. In fact a tube front end and class D output is quite affordable, and can have extremely high quality sound reproduction. But the entire solid state amps, do well because they now use Mos-Fet frontends.

Then there is the addition of size, weight, and current draw. I used to worry about current draw in some location, starving the tubes for power. Now no problem, Class D Genzler 800 (or even the Crown XLS 1500) pulls hardly any AC current. It is all light weight, so I don't need a crew to move my stuff, and the footprint is minimal. Plus they can put out transients easily due to the extremely higher wattage capability.

And I no longer get my old tube tester out checking tubes and trying to match them.

Bass players need 10 times the output compared to guitarists, in order to compensate for the transients and perceived volume levels. So your guitar player may have a 30 watt Tube amp (somewhat easier to deal with and construct), while you may need 300 watts or more. In a tube amp, that is much more to afford and deal with, just saying.

Simply loaded with factually incorrect information. Virtually all of it.

I left the audiophile design world over 35 years ago because facts took a distant second place to mythology and misinformation.

 

[Drgonzonm]

This is all assuming that your guitarist with the 30w amp is turning it up all the way. Pretty much none of the guitarists I've ever worked with have done that. I'm trying to think of one who did and I can't think of a one.

I heard Neil Young modified 5E3's would run about 6 months before requiring retubing or other major maintenance. It my understanding, that the 5E3, had a undersized O/T and the 6L6's were even harder on the amp than the 6v6's. What other changes he made, are somewhat of secret.
O/T failure can cause power tube failure, but it wasn't because the tube was defective.

 

[McTred]

Do yourself a favor and check out the Darkglass 900 before you drop coin on a new bass amp.

I bought one based on reviews from this site, and as much internet research as I could do... I am so happy with the tone I'm getting now that I'm probably going to sell my Eden gear.

Want crystal clear? It's got that
Want the best sounding bass distortion I've ever heard? It's got that
Want anything in between with tons of eq options? It's got that

 

[dannydabiker]

Getting older and tired of schleping a six space rack, pedals, etc. around. I got a TC Electronics RH450....size of a cigar box and, blind test it...the thing does what no other solid state I have played does...it handles it all and the tone control is immense.

 

[Drgonzonm]

Unlikely under the best of conditions. The market is about 1000x too small to make that kind of investment in basic research, tooling and production of such advanced technologies.

But it would make one heck of doctoral dissertation or a side project at LANL or Sandia. Where else are you going to find the Electron microscopes, vacuum equipment, and grad students to do the work? Would the PhD be in physics, material science or electrical engineering? Can you imagine assembling some of the technology you see in the U-tube videos.

 

[JKdemeter]

Having built tube pre-amps for 35 years. I always used a more conservative voltages (250V). That has paid dividends in tube life. When Lee Sklar donated his pre-amp back to us as a gift (it was #1) I was amazed the tubes were still good. I guess there a good deal of luck involved as some times, especially in Guitar amps, Ive had tubes fail within minutes, days or weeks. You never know. Output tubes are the least trust worthy as they work harder and are more susceptible to physical damage. Although I have designed and built Tube Amplifiers. I think the for Bass, the tube front end and solid state output is the best of both worlds.

 

[Walk_the_walk]

I have rarely been able to find an amp that sounds like a tube amp. I own a customized 70's Fender Bassman Ten with 4-10" EV speakers and Groove Tube tubes, which I love. I also have a Peavey Session Bass head with a built in parametric EQ that comes close. But having owned solid state amps in the past (I also have a small Hartke), they're just not the same. A tube amp is a tube amp is a tube amp. If you like those warm harmonics, buy a tube amp.

 

[agedhorse]

But it would make one heck of doctoral dissertation or a side project at LANL or Sandia. Where else are you going to find the Electron microscopes, vacuum equipment, and grad students to do the work? Would the PhD be in physics, material science or electrical engineering? Can you imagine assembling some of the technology you see in the U-tube videos.

Indeed, the work would probably be more interesting to the "grad-servants" than cleaning the bathrooms, making copies and worshiping their professor, right?

 

[Drgonzonm]

Indeed, the work would probably be more interesting to the "grad-servants" than cleaning the bathrooms, making copies and worshiping their professor, right?

Been there.

 

[JimmyM]

Having built tube pre-amps for 35 years. I always used a more conservative voltages (250V). That has paid dividends in tube life. When Lee Sklar donated his pre-amp back to us as a gift (it was #1) I was amazed the tubes were still good. I guess there a good deal of luck involved as some times, especially in Guitar amps, Ive had tubes fail within minutes, days or weeks. You never know. Output tubes are the least trust worthy as they work harder and are more susceptible to physical damage. Although I have designed and built Tube Amplifiers. I think the for Bass, the tube front end and solid state output is the best of both worlds.

As always, many will agree with you and many won't. I would pretty much always prefer a hybrid setup over a full-on SS setup, sure, but there's just something about a good full-on tube amp that makes me have to play them. That said, on today's gig, it's outdoors and the stage is way too tiny for 8 people so I'm bringing my little 25w SS practice amp

 

[EatS1stBassist]

Pushin’ 70’ years old/new. I recently pulled my 89 pound SWR TRIAD out of storage with a fairly heavy Acoustic B600 Head. I love the sound of this rig.
When I was younger (70’s) I carted an SVT ALL TUBE Head and it’s ridiculously heavy Cab with nine tens. Fantastic sound it would literally push massive air. Everything I owned after that Ampeg was compared to it and came up short. Until I got the Acoustic B600 and matched it up with the SWR TRIAD. WOW!! Great sound!! Now, as the years have rolled by, I don’t have the ability to lift/push/tug even this rig around. So recently I plugged into one of my Behringer Bluetooth 1000 watt powered PA SPEAKER. GREAT SOUND!! Lightweight!!
Really don’t know how it would sit in the mix for live work but here the studio It sounds great. $300-$350 For Bluetooth.