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Ampeg PF-50T head

Issue #39

Recently, I was browsing one of the bass community's most active forums and it occurred to me that there’s a lot of discussion about the current market for downsizing solid state amplifiers to super high power lunchbox sized packages. I’m all for it and I have a few real favourites in the department. But that said, I also do enjoy a great sounding valve amplifier too - indeed I have one myself and have owned some truly colossal beasts in my time, but they do have one inherent handicap for us musicians on the go. In the case of my current ’68 beauty, even without its classic birch ply cabinet securing the contents, it’s still a big ‘un despite being at least manageable in weight. Many are not too friendly in that department either!

What if we could squeeze all that valve goodness in to a smaller box and still have enough volume to keep up with a drummer? So far my investigations suggest that 100 Watts all tube still has to be of a physical size that puts it outside of the ‘lightweight market’, but my search continues…But has Ampeg come to the rescue?

New to the PortaFlex range are two all-valve amplifiers and a new cabinet featuring a single 12” speaker. We've just had the more powerful of the two amplifiers in for review. The little brother of the PF-50T is a 20 Watt model while our version, as the name suggests, is a 50 Watter. But before you shudder at figures like 20 and 50, don’t assume such low figures in comparison to the truly mind boggling 800W D Class units on the market today are going to be 'home practice only’ amplifiers. The 50T we had on review appears to be pretty capable in the studio, as well.

The front panel will be familiar for anyone who has used Ampeg amplification in the past and simplicity is the way forward for a true plug-and-play approach.

Two inputs comprise guitar connectivity, one of which is attenuated to keep instruments with a high output under control - though using the non-attenuated input will allow you to quickly overdrive the pre-amplifier, if that’s what you want. You’ll notice in the video that my input gain was set very low as I wanted to ‘ride’ that point of clipping for a nice fat sound.

The PF-50T features an input gain control on the left hand side and it is followed by the classic ‘ultra hi’ and ‘ultra lo’ buttons which, even before utilising the other tone controls, give way to wide tone shaping and should definitely be experimented with. If however that isn’t enough then it's off to the three band EQ which features Ampeg’s famous five way midrange selector, which is like a fixed semi-parametric EQ that provides preset frequencies for you to use to sculpt your sound. Finishing up, you have a treble control and a master volume.

We were able to do some really cool impressions of Motown bass lines using the Precision pickup on my Fender bass but winding the gain up, we could also make the sound edgy and more aggressive. That makes this Ampeg a lot more that a one trick pony, but it does have its own distinctive sound, especially when used in conjunction with a PortaFlex cabinet. It's not exactly 'hi-fi' in that modern bass amp style, which means you might either love it or hate it, depending on your taste. From our perspective, we at GI Towers we are all for products having strong characters, so we think it's a definite plus!

Round the back of the PortaFlex valve head it is, for the slightly geeky types, (yes, that would be me) actually rather cool! As with any valve amplifier, you are greeted with main power and standby power switches. I briefly explain why there are two in the video. Next to that, a standard power input socket.

Ampeg has also very kindly saved us the cost of taking our valve amplifiers to a tech every time we install new power amplifier valves, thanks to the inclusion of a biasing device. Refer to the manual to see how this handy utility works!

When it comes to taking your amplifier signal out to external devices, such as PA or recording kit, Ampeg has provided another very useful inclusion. Not only do you get the usual DI output that would be normal on pretty much any modern bass amplifier -  they go one step further. Not only do you have access to your bass signal coming out of the pre-amplifier section of this head, according to Ampeg’s Dino Monoxelos, another XLR socket taps the signal at the output transformer instead to send off to your project studio. This means you get to record the tone through the power amplifier valve section too! Furthermore, and somewhat unusual for a full valve amplifier, you can use this head without a cabinet connected! Run the rich valve tones direct into your digital recording system and you can record in silence! Happy neighbours! Off the top of my head as I write this, I was thinking it’d be great to run the output transformer DI straight in to a DAW, then use a classic Ampeg cabinet I.R* to recreate the rest of the signal chain. Yeah, I really like the idea of that.

*Further reading - Cabinet Impulse Responses (groan - Ed).

Rounding up, well this is a super little head and despite the ‘heavy metal’ components on show, it still only weighs in at around 8Kg (about 9lbs), which I think is acceptable considering what is required to make a valve amplifier deliver a great sound: transformers for output and power, the valves themselves etc. 

Whether or not the outline is pleasing to the eye, I guess that’s a personal thing as I suspect some may like to have everything enclosed in a conventional casing. However, if you are planning on leaving the Ampeg PF on a shelf in your home studio, whip the metal cage off to show off those glorious valves gently glowing! It’d be the right thing to do, especially if you have Hi-Fi audiophile tendencies!!

This is a well thought-out product from the Ampeg team who are to be congratulated for making something that has a real character to its sound, offers genuinely useful, and in some cases unique, features and doing a job that not many other bass amps can do. 


Issue #76

Black Stone Cherry | Eddie Van Halen Tribute

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