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Product 483011

ISP Technologies Theta 300W Guitar Amp Head

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The Theta Amp Head offers a unique approach to the guitar amplifier, providing two selectable input pre-distort preamplifiers. Using the Theta guitar...Click To Read More About This Product

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OVERVIEW

Monstrous power you can shape any way you want.

The Theta Amp Head offers a unique approach to the guitar amplifier, providing two selectable input pre-distort preamplifiers. Using the Theta guitar amplifier head is like having two low-noise, extremely high quality preamp pedals at the input of the amplifier. Each front-end pre-amp has gain, bass, mid level, mid sweep and treble which provides amazing pre-distort tone shaping. The amplifier's "Clean" and "Distort" circuits have the same post distort tone shaping. Tone beyond your wildest dreams! Extreme sonic flexibility. The Clean channel has additional tone shaping with the inclusion of a Presence control, providing more than 20dB of high frequency boost. You want gain? The Theta amplifier head has greater than 140dB of gain and you can control and make it useable because of the included dual independent full-featured Decimator Noise Reduction systems.

The Theta incorporates Dynamic Saturation Modulation™, which delivers the actual feel of a saturated tube power amplifier. The Theta also packs a huge punch; the internal D-CAT power amplifier delivers more than 300 watts RMS into a 4-ohm load and 150 watts into an 8-ohm load. Derek Bowers, renowned IC design engineer from Analog Devices and Buck Waller of ISP Technologies, developed the patent pending D-CAT power amplifier technology. The D-CAT is a super high current power amplifier technology capable of driving a .5-ohm load. This means that the D-CAT amplifier delivers excellent transient response and punch.

FEATURES
  • Dual Amplifiers Clean / Distortion
  • Clean Channel Controls — Presence—Bass—Mid—Mid Sweep—Treble—Decimator—Reverb—Output Level
  • Distortion Channel Controls — Gain-Bass-Mid-Mid Sweep-Treble-Decimator-Reverb-Output Level
  • High Quality Digital Reverb
  • Dual Input Preamplifier
  • Both Preamplifier Controls — Gain-Bass-Mid-Mid Sweep-Treble
  • Solo Boost
  • Effects Loop
  • 300 Watt RMS D-Cat Power Amplifier

Sound that's bigger than big! Call or click today to order.

SPECIFICATIONS
  • 45 lbs.
Reviews
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Review Snapshot

by PowerReviews
ISP TechnologiesTheta 300W Guitar Amp Head
 
4.6

(based on 13 reviews)

Ratings Distribution

  • 5 Stars

     

    (9)

  • 4 Stars

     

    (3)

  • 3 Stars

     

    (1)

  • 2 Stars

     

    (0)

  • 1 Stars

     

    (0)

Most Liked Positive Review

 

Outstanding!!!!!

Percussive, responsive, and clear even when you slap serious gain at it. The clean channel is the sweetest thing I have ever heard.
Hands down the best amp purchase I have ever...Read complete review

Percussive, responsive, and clear even when you slap serious gain at it. The clean channel is the sweetest thing I have ever heard.
Hands down the best amp purchase I have ever made. I own a 6505+ and a 6534+ and this is by far, IMHO, the best sounding, most versatile Guitar Head I have ever owned.Truly a cut above.

What you also get with the amp is a level of customer service second to none. Buck and Shelley have done an incredible job staying true to their roots. You actually matter to them. And, they are genuinely interested in your experience and want your feedback. In fact sometimes they even personally answer the phones. Truly remarkable in today's cookie cutter Faceless market.
Hand made.
They are pricey. But, you won't be disappointed.

VS

Most Liked Negative Review

 

Good sound, Weak customer service

I've had theISP for awhile. Tried to get some help from the company Waller, but Shelly , the cust service rep, was less than helpful. So, when it works- sounds good,...Read complete review

I've had theISP for awhile. Tried to get some help from the company Waller, but Shelly , the cust service rep, was less than helpful. So, when it works- sounds good, but when it doesn't- good luck.

Reviewed by 13 customers

Displaying reviews 1-13

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(2 of 2 customers found this review helpful)

 
5.0

Outstanding!!!!!

By Scott Shepherd

from Toronto

Comments about ISP Technologies Theta 300W Guitar Amp Head:

Percussive, responsive, and clear even when you slap serious gain at it. The clean channel is the sweetest thing I have ever heard.
Hands down the best amp purchase I have ever made. I own a 6505+ and a 6534+ and this is by far, IMHO, the best sounding, most versatile Guitar Head I have ever owned.Truly a cut above.

What you also get with the amp is a level of customer service second to none. Buck and Shelley have done an incredible job staying true to their roots. You actually matter to them. And, they are genuinely interested in your experience and want your feedback. In fact sometimes they even personally answer the phones. Truly remarkable in today's cookie cutter Faceless market.
Hand made.
They are pricey. But, you won't be disappointed.

(1 of 1 customers found this review helpful)

 
5.0

HIGH FIVE BRO!

By Frankie

from Missouri

See all my reviews

Comments about ISP Technologies Theta 300W Guitar Amp Head:

This is the best solid state amp ever made. Even the JC 120 does not compare. The Theta delivers beutiful cleans and the most hellish distortion that has ever been. You can dial in a nice open raw JCM800 tone or turn the sweep control and get a nice compressed Rectifier sound except with even more gain. My friend Sean and I high five over this thing for hours. Buy it. It will blow your face off.

(1 of 1 customers found this review helpful)

 
5.0

incredible

By genocide roach

from co springs, co

Comments about ISP Technologies Theta 300W Guitar Amp Head:

ive played many show worthy guitar amps. mesa triple rec, marshall jvm, peavy 6505, ashdown fallen angel, hughes and kettner switchblade... they all have their pros and cons. but the problem i always came across is that i had to chose between a good distortion tone or a good clean tone. both are incredibly important to me, and this amp delivers. the 2 seperate pre amps give you 2 distinc tones. the first gives you really tight and articulate sound. the second gives you more fuzz and feedback, for a more old school feel. both channels have incredible amounts of gain. i use preamp 1 99% of the time.the distortion crushes and but is still defined. and the clean is beyond anything ive played, even a fender.lastly, the reverb on this head is fantastic. many of the heads i was looking at didnt even have reverb built in.get this amp, its worth the cash.

(1 of 1 customers found this review helpful)

 
4.0

Very good, versitile amp

By Setsuko1984

from Gainesville, Florida

Comments about ISP Technologies Theta 300W Guitar Amp Head:

I have owned this amp for several years now, so I feel like I can comment on the quality of this amp. Pros: Responsive eq on all channels. The noise gate is the best I have ever used. Dirty channels are great at all volumes (speakers have a lot to do with this). Clean channel with the gain turned all the way up has great break up that goes to a warm, fat clean if roll off the volume.Cons: Clean channel without the preamp engaged is useless in a band setting. The amp is a little bass heavy, which tends to be the case with a lot of solid state amps. If you use the mid frequency knob and turn down the bass it works just fine. The ribbon wire for the preamp has a tendency to come undone. If you solder it in it will be fine. Over all it's a great amp, and I wouldn't trade it for the world.

(1 of 1 customers found this review helpful)

 
5.0

Just an Incredible Amp

By Frankie the Brutal

from Kansas City, Mo.

See all my reviews

Comments about ISP Technologies Theta 300W Guitar Amp Head:

This is easily the finest amp I've ever played. It has a nice round, responsive distortion and an unbelievable clean channel. The sound options with the two built in pre-amps are amazing. This is no modeling amp, it is its own. Many people will assume that it's too expensive for a solid state amp but there isn't any other amp sounds this good for any price!

(1 of 1 customers found this review helpful)

 
5.0

Finally!!!

By Frankie the Brutal

from Kansas City, Mo.

See all my reviews

Comments about ISP Technologies Theta 300W Guitar Amp Head:

I've been playing for around 12 years or so and have played so many differant amps; Peavey 5150, Marshall tube and solid state amps, Crates, and Mesa Boogie. Now finally I've found in the ISP(intelligent signal processing) Technologies Theta head exactly what I want to sound like.I play my own brand of bluesy death metal. I play an old Gibson SG1 and a Gibson '67 Flying V Reissue. I needed an amp with a nice clean channel and an absolutely evil high gain channel. The ISP Theta is it. The clean channel is stunning and beutiful. If you use the built in pre-amp you can get just the right amount of break up for a bluesy clean, a lot like using a great overdrive like a tube screamer or a Maxon only much more musical sounding. The dirty channel has more gain than any other amp I've ever played. The distortion sounds amazing, it's not wimpy and thin like other solid state amps I've played. If you played this amp blindly you would be hard pressed to believe it isn't tube driven. This is not a modelling amp like a Line 6, this amp is it's own beast. If I had to pick an amp it sounds like I would probably say an old Mesa Boogie Dual Rectifier except this amp has more gain, more tone shaping capabilities and a better clean channel.The folks at ISP have finally done what we all thought was impossible. They have finally produced a solid state amp that sounds better than tube amps. I had lots of questions before I bought this amp so I contacted ISP and they couldn't have been better to me. Musicians Friend has a great deal on a truly boutique amp so buy this now before the guy next door one ups you.

 
3.0

Good sound, Weak customer service

By Zombie

from In a house of blues

About Me Professional Musician

See all my reviews

Pros

  • Portable

Cons

    Best Uses

      Comments about ISP Technologies Theta 300W Guitar Amp Head:

      I've had theISP for awhile. Tried to get some help from the company Waller, but Shelly , the cust service rep, was less than helpful. So, when it works- sounds good, but when it doesn't- good luck.

       
      4.0

      ISP Theta Crunch Machine!!

      By Greg E Noll-FnjWL

      from Northern california.

      See all my reviews

      Comments about ISP Technologies Theta 300W Guitar Amp Head:

      The ISP Theta is without a doubt the best amp I've ever owned. It's completely solid state, but has the sweetest tube-tone ever. The thing with this head is, it's not just a "plug in & play" amp. With so very many features, you need to spend some time with the controls to find "your" tone. For my crunch channel, I set my gain at about noon (this is plenty, trust me) and most of my EQs a little past noon, with the sweep at three o'clock. I keep the EQs of the 2nd preamp set at noon & add or subtract frequencies as needed. I also bridge the FX loop with a patch cable & set the loop volume at around 3 o'clock as well. This really sweetens up the tone alot. With these settings, I get a kind of "Plexi on steroids" tone. Very sweet. This head also has a killer clean channel. VERY clean, or a tad gritty with the gain eased in a bit. This is a very complex, versatile amp. The Theta has put me in tone heaven!

       
      5.0

      Theta Kicks Major Booty, Baby!!

      By Greg E Noll

      from Northern California.

      Comments about ISP Technologies Theta 300W Guitar Amp Head:

      I first encountered the ISP Theta crunch machine at winter NAMM a couple years ago. I tried it at their booth, asked what kind of tubes were in it, and my jaw dropped when I was told that it was all solid state! I fell in love with this head then & there, and became an endorsing artist. Because this amp is so complex, the trick is to spend time experimenting & tweaking, dialing in your dream tone. It's in there, trust me. I've owned this head for over a year now, and am getting the sweetest, crunchiest tone I've ever achieved - like a Plexi on steroids. Want uber gainy Mesa tone? It's in there, too. In short, this head rules...

       
      5.0

      Monster Head

      By Anonymous

      from Undisclosed

      Comments about ISP Technologies Theta 300W Guitar Amp Head:

      I just purchased one of these monsters and I have to say that it's simply amazing. The clean channel is clear and chimey if you want it to be. If you don't want it to be egage the clean channel pre amp and turn up the gain and you'll have a nice bluesy break up to your sound.The dirty channel is the most incredibly beautiful taste of brutal power you can imagine from an amp. This is not a tube amp but the distortion is round, responsive and abundant. I've never heard an amp with as many options to fine tune your desired tone.I've always been a tube amp guy but the day is finally here when solid state has surpassed tube technology in sound quality. I own both Marshall and Peavey heads and the Theta is far beyond their capabilities. I finally sound exactly the way I've always wanted to.

       
      5.0

      ISP Technologies Theta

      By n0HgAJe7O

      from New Mexico

      Comments about ISP Technologies Theta 300W Guitar Amp Head:

      After shopping around for a new amp for probably about 6 months, and trying almost anything I could possibly get my hands on, I found this. I was very impressed with the specs so I said hey I'll try it and return it if it's not good. Turns out it's better than any amp I've ever played. No marshall, krank, mesa boogie, or peavey can compare to the quality of not only the distortion but the clean channel is flawless. Any style can be played on this amp. I use it for metal or smooth jazz. Everything sounds Great!

       
      4.0

      almost perfect

      By Bolistic 6 stringer

      from Michigan

      Comments about ISP Technologies Theta 300W Guitar Amp Head:

      I have had this amp head for about just over 4 months, All I have to say is that this amp headis the sweetest sounding clean and rhythm,as for distortion forget it sounds muddy if you increasebass or midrange tone That's my only gripe about this Amp head to bad thats what I bought it for, but decided to keep it because nothing out there compares to the clean channel, maybe I have a bad distortion channel according to ISP they told me to turn down the bass which is 12:00 position so no bass otherwise sounds clear but weak, I have put a distortion pedal on the clean channel and had better luck, Not for metal heads Like Me, butI just cannot express enough how good the clean channel is say like stairway to heaven sounds Awesome, If I were you I would listen to one first then see if you like it, Its not the most expensive amp head, but still its an investment.

       
      5.0

      Great for Extreme Metal

      By Necrocenturion

      from Bloomington, MN

      See all my reviews

      Comments about ISP Technologies Theta 300W Guitar Amp Head:

      The ISP Theta head is a powerful beast. 300w solid state is nice when you want to be heard, especially if you're the only guitarist in the band. I've been using a peavey JSX for the last 5 years until I found the Theta head. Very clear distinct distortion and clean channel. The only flaw I think is the fact you have to use the footswitch to use the preamps, FX loop, solo boost, and reverb. Its a great plug and play amp. You can use the distortion right out of the amp without using any of the preamps and get a nice decent distortion. I like to add a lot of rack effects to the clean channel, create my own brutal sound, and make use of its 300w of non-tube power. Sounds like a tube amp without the temporary tube life. Doesn't sound pixilated or digital like a Randall Cyclone. The "Decimator" noise gate is the best. Better than the Hush super C. Stops and Starts are like turning a switch on and off. The Theta head works great with a Marshall 1960 4x12 cab (75w Celestions). Very brutal!

      Displaying reviews 1-13

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