Advice on a new amp

[dystrust]

Re: Advice on a new amp

Nah that's +10dB

This is more like 22 >> 30w

Sorry man, but LPB is correct; double wattage = 3db.

Pete Townsend wanted an amp that was twice as loud as his JTM45, so Jim Marshall made the JTM45/100. If he really wanted to be twice as loud (and not simply have twice the power) he'd actually need 500W to be twice as loud as 50W. (and I know that a JTM45 is more like 35W)

Edit: Forgot to mention that you can also add 3db by doubling speaker count. At the same wattage a 2x12 will be 3db louder than 1x12.

 

[Gtrjunior]

Re: Advice on a new amp

Good info...I didn’t know that.

 

[AxlOz]

Re: Advice on a new amp

Ah - but does it make us twice as awesome...?

I think a 4x12 would be needed for that. And then if you stack two 4x12's you'll be 3 x as awesome. Its a logarithmic curve...

 

[texred]

Re: Advice on a new amp

Hi guys, I've started a project where my trusty Fender Blues Jr simply isn't keeping up. The tone I'm getting through it is good for what we're doing (garage/rock/blues sorta thing - we even use some slide guitar!). So I think I just need a bigger Blues Jr... ?

My offsider plays a Sunn Model T 50w combo and a Rickenbacker 330, which he's getting some big fat juicy tones out of, so I want to hit those higher, raspy, dare I say 'ice pick' tones. Maybe be a tad cleaner than he is too as his tone gets quite woolly. I play a US Std strat.

My initial thoughts were to get a Fender Hot Rod Deluxe - similar design to the Blues Jr, but 6L6 tubes @ 40w.

Then I saw there's also a Fender Blues Deluxe - also 6L6 @ 40w.

Then today I remembered the Peavey Delta Blues amps, which I've never tried.

Or should I go all out and get a Fender twin? We will be gigging soon so I'd prefer something portable though. The twins are HEAVY...

Anyway, over to you guys, what do yas reckon?

Peavey vypyr VIP 3 = stack of Marshalls

 

[Adieu]

Re: Advice on a new amp

Sorry man, but LPB is correct; double wattage = 3db.

Pete Townsend wanted an amp that was twice as loud as his JTM45, so Jim Marshall made the JTM45/100. If he really wanted to be twice as loud (and not simply have twice the power) he'd actually need 500W to be twice as loud as 50W. (and I know that a JTM45 is more like 35W)

Edit: Forgot to mention that you can also add 3db by doubling speaker count. At the same wattage a 2x12 will be 3db louder than 1x12.

Oh yeah true.... +10db is double VOLUME

 

[AxlOz]

Re: Advice on a new amp

Update!

Today I tried a Ltd Edition Blues Deluxe - it had cream coloured tolex and a Jensen P12Q speaker. Sounded great! Very simliar to the hot rod deluxe tone, but the gain structure was a little easier to dial in, and it didn't get as dirty. I liked that it had a bright switch also. So overall a nice amp that I could definitely enjoy, but there was one drawback - I also tried a '65 Deluxe Reverb Reissue....
That thing was just beautiful and lush. I was in a tiny room so cranking it was painful and I couldn't get it to break up, but my god those clean tones were just amazing. I may be swayed towards one of these now - with an OD pedal for dirt if need be...

 

[IM4Tone]

Re: Advice on a new amp

Edit: Forgot to mention that you can also add 3db by doubling speaker count. At the same wattage a 2x12 will be 3db louder than 1x12.

:nono: Just isn't so.

 

[treyhaislip]

Re: Advice on a new amp

Update!

Today I tried a Ltd Edition Blues Deluxe - it had cream coloured tolex and a Jensen P12Q speaker. Sounded great! Very simliar to the hot rod deluxe tone, but the gain structure was a little easier to dial in, and it didn't get as dirty. I liked that it had a bright switch also. So overall a nice amp that I could definitely enjoy, but there was one drawback - I also tried a '65 Deluxe Reverb Reissue....
That thing was just beautiful and lush. I was in a tiny room so cranking it was painful and I couldn't get it to break up, but my god those clean tones were just amazing. I may be swayed towards one of these now - with an OD pedal for dirt if need be...

Deluxe Reverb is an absolute killer amp! Definitely pricier but a super solid amp with incredible tone.

 

[dystrust]

Re: Advice on a new amp

:nono: Just isn't so.

Be my guest: http://myhometheater.homestead.com/splcalculator.html

As an example I entered 100db sensitivity, 20W amp, 3ft, and 1 speaker. The output is 113.8db, while changing to 2 speakers results in 116.8db. Going from 2 speakers to 4 results in 119.8db...

With given wattage and speaker sensitivity, it's simple math and the formulas don't lie or change. Doubling speaker count with a given wattage, distance, and sensitivity results in 3db more volume. Physics doesn't care if you agree or not.

 

[Mincer]

Re: Advice on a new amp

I'd say to consider a Pro Reverb, if you can find one. It has more headroom than a Deluxe, but isn't the beast that the Twin is. They aren't as collectible as either (although I like them more than both), so there is a good chance you can find a good price on one.

 

[AxlOz]

Re: Advice on a new amp

The pro reverb could be a winner, though I'd be most interested in a 1x12 version. Seems many of the older SF ones are all 2x12. 40w would be perfect too!

 

[IM4Tone]

Re: Advice on a new amp

Be my guest: http://myhometheater.homestead.com/splcalculator.html

As an example I entered 100db sensitivity, 20W amp, 3ft, and 1 speaker. The output is 113.8db, while changing to 2 speakers results in 116.8db. Going from 2 speakers to 4 results in 119.8db...

With given wattage and speaker sensitivity, it's simple math and the formulas don't lie or change. Doubling speaker count with a given wattage, distance, and sensitivity results in 3db more volume. Physics doesn't care if you agree or not.

This part is correct.However, when you changed to multiple speakers, you neglected to adjust the wattage to the value that each speaker sees (which is 10 watts; then 5 watts) Has nothing to do with violation of laws of physics, but their MISAPPLICATION! Read the instructions.

 

[jeremy]

Re: Advice on a new amp

The pro reverb could be a winner, though I'd be most interested in a 1x12 version. Seems many of the older SF ones are all 2x12. 40w would be perfect too!

the modern 1x12 ones arent the same as the old blackface and silverface ones. the old bf 2x12 are damn near the perfect fender reverb amp for many things and this is from someone who has a bf deluxe reverb, has had a bf twin and still has a sf dual showman reverb. 6l6 + 2x12 = 40w of great tone

 

[dystrust]

Re: Advice on a new amp

This part is correct.However, when you changed to multiple speakers, you neglected to adjust the wattage to the value that each speaker sees (which is 10 watts; then 5 watts) Has nothing to do with violation of laws of physics, but their MISAPPLICATION! Read the instructions.

I did a ton of extra research, and it turns out that 3db is a simplified fudge factor and possibly a bit of internet guitar lore, so I apologize for stating it as an absolute.

It turns out that the actual science of connecting multiple speakers is extremely complicated and depends on things like how the speakers are connected, the size and configuration of the cabinet, and how the amplifier's output stage responds to changing impedance. There's also an absolute limit to increased volume when the total area of all connected speakers starts to cause phase cancellation a certain frequencies.

I'll amend my earlier recommendation to state that (generally speaking) connecting an additional speaker in parallel will provide a few dbs of extra volume at the same wattage.

Another viable option (that always works) would be to replace the speaker in the Blues Jr. with something more efficient.

 

[IM4Tone]

Re: Advice on a new amp

I did a ton of extra research, and it turns out that 3db is a simplified fudge factor and possibly a bit of internet guitar lore, so I apologize for stating it as an absolute.

It turns out that the actual science of connecting multiple speakers is extremely complicated and depends on things like how the speakers are connected, the size and configuration of the cabinet, and how the amplifier's output stage responds to changing impedance. There's also an absolute limit to increased volume when the total area of all connected speakers starts to cause phase cancellation a certain frequencies.

I'll amend my earlier recommendation to state that (generally speaking) connecting an additional speaker in parallel will provide a few dbs of extra volume at the same wattage.

Another viable option (that always works) would be to replace the speaker in the Blues Jr. with something more efficient.

Yes, the internet lore makes people believe what is not fact. One of the highest laws of physics is The Conservation of Energy. If there is only one active (energy generating) component, i.e. the amp (@ 20 watts), the passive components (speakers) cannot create additional energy (assuming the same efficiency). They convert electrical energy to sound energy. If each gets half of the electrical energy, each produces half of the sound energy.

Yes, adding additional speakers is extremely complex, so we say "all other things being equal", but that's near impossible to achieve. Multiple speakers will yield increased dispersion, giving a genuine sensation of increased volume, but there can be NO real increase....None. :beerchug:

 

[dystrust]

Re: Advice on a new amp

Yes, adding additional speakers is extremely complex, so we say "all other things being equal", but that's near impossible to achieve. Multiple speakers will yield increased dispersion, giving a genuine sensation of increased volume, but there can be NO real increase....None.

The reason that multiple speakers seem louder is because increasing driver surface area results in an increase in net efficiency for the system. You're correct that you can't create energy out of nowhere, but an increase in efficiency allows a given amount of electrical energy to be converted into more sound energy.

In my research I also saw mentions of series vs parallel wiring making a difference as parallel wiring won't experience voltage drop and the resulting signal loss. I'm not an EE, so I don't really understand how halving voltage vs. amperage would make a difference but it apparently does.

 

[AxlOz]

Re: Advice on a new amp

Update!
So I've found something that I was not expecting would tick the box for me, but it may be a great outcome - a Supro Supreme!

Its a 1x10 combo, 25w, 6v6 based with really basic controls.

I tried it at rehearsal last night and it just killed! They sound a bit 'normal' at low volume, but I had the volumes (plural - it has 2 channels that cascade or something like that) running at about 7 and it just came to life and sounded amazing. Very clear and articulate, but with just enough crunchy breakup.
The real interesting thing is how well it handled low end. I was expecting a weaker bass response due to the 10" speaker and smaller cabinet size but it sounded fatter than other 2x12's I've played, and much fatter than my Blues Jr. Thick and articulate with super sweet fender-esque mids and highs. No reverb though, but I rarely use that in a live setting, most venues add enough naturally.

I'll try it again at next rehearsal and see how she fares for round 2.

 

[Mincer]

Re: Advice on a new amp

Supro has been coming out with nice amps lately. They aren't the cheapies that were talked about years ago. They are nice, pro amps these days.

 

[AxlOz]

Re: Advice on a new amp

Yeah I was very impressed to say the least. It was also dead quiet at idle.. Felt very high quality.

 

[treyhaislip]

Re: Advice on a new amp

Supro is not an amp I think about regularly–sorta hard to find.

But man they do sound awesome!