McIntyre BluesMaker II

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McIntyre BluesMaker II Front

McIntyre BluesMaker II Rear


Designed by John McIntyre, who has been modifying and building guitar amplifiers for years. His articles in Guitar Player magazine on amplification mods have set standards in tone excellence. Actodyne General Inc. has teamed up with John to create a line of amplifiers based on his original "Bluesmaker" series. Designed for the guitarist, who demands tonal variations not found on conventional low powered amplifiers. The Bluesmaker MKII is a masterpiece of complex tone voicings with radical new tone complexity in the midrange area. Long known for guitar tone enhancement, designer John McIntyre has designed new proprietary tone circuitry that is cutting edge vacuum technology. You can make your guitar feed back even at low levels. The key to great tone is having great power tube distortion. The Bluesmaker MKII provides great power tube distortion at volume levels that won't make your head cave in. This makes the amp perfect for home studio, or apartment playing. Class A operation assures rich harmonics and a warm tone.

Bluesmaker reviewed in Guitar Player, May 1994, page 58.


  • Stereo, all-tube recording amp. 1 EL84 (6V6 available) per side. 3 watts per side (left, right). Class A.
  • Speaker Out. Selectable Speaker Impedance; 4-8 ohm selector
  • Built-in dummy load for each channel (left, right).
  • Built-in speaker simulator (cab-sim filter) for each channel (left, right). Independently switchable between Smooth (Celestion 12") or Brite (Jenson 10").
  • Can drive speakers or use headphone jack even while using built-in speaker load.
  • Stereo tube fx loop
  • Fan cooled
  • Draws from the basic concept of the Bluesmaker amp modification described by John McIntyre in Guitar Player, Feb 93 [investigate] with greately enhanced tone control.
  • Clean and crunch channels
  • 4 midrange controls; 4 Tone Circuits.
  • From Canada.
  • Magic Eye acts as a radiant VU meter, available only in the JDS Model A Electro-Furniture Cabinet.
  • Controls: Input, Gain (with Pull Boost), Bass, Midrange, Treble, Presence, Left-Right Master Volume Controls, StandBy, On/Off.

Review of the Lexicon Signature 284

What makes it so special? Well, one key factor is its low output power which allows you to get the sinuous touch and gorgeous tone that only a fully-cranked all-tube amp can deliver. With only 3 watts per side, its low-power design makes it ideal for recording as well as live performance applications where high volume levels are undesirable. The Signature 284's unique design combines a high-gain preamp with a low-wattage, stereo Class A power amplifier.The preamp section uses three 12AX7 tubes and incorporates a switchable high-gain stage and beautifully voiced tone controls. To put the finishing touch on the 284's tone, a stereo power amp uses two EL84 tubes in a Class A configuration. A tube-driven stereo effects loop lets you place effects in-line between the preamp and power amp for sonic effects that can't be obtained at the console. Simultaneous outputs let the amp drive any combination of stereo speaker, balanced recording and slave amp outputs. The speaker outputs can handle 4 or 8 ohm cabinets. Built-in speaker simulation lets you select "smooth" or "bright" independently for each recording output. For silent recording, the passive load is automatically connected when the speaker is disconnected. Because the slave outputs tap the signal after the power amp, they carry all of the Signature 284's characteristic tone and can be connected to any power amp and guitar cabinets for greater performance volume.

Review in Sweetwater Sweet Notes - 1998

Original Owners Manual

Signature 284 FAQs

Signature 284 : Signature 284 General Questions

What type of EL84 power tubes are shipped with the machine?

Sovtek with a 5 hardness rating.  These can be replaced with the EL84 tubes of your choice. Note: tubes should be replaced only by qualified service personnel.

Last reviewed: 11/20/2000

What outputs should be used with a recording console?

Use the recording outputs.

What is the magic eye and what does it do?

The magic eye is an option on a limited edition of the Signature 284 Amp. It is a vintage tuning eye from the 1940's. New parts -  Old Stock. It functions as a VU meter, which will show a full 3 watts max and also assists in tuning a guitar. For example when two strings are in tune the eye will show a steady non fluctuating glow when those two particular

strings are struck. And it also visually makes the player feel good.

Last reviewed: 9/22/99

What famous people are using the Signature 284?

Users of the Signature 284 include Alan Holdsworth, Greg Howe, Blues Saraceno, Carl Vereheyen and Eddie Kramer. See the artists page at for updates on Customer Shop Users.

What are the dimensions of the Signature 284?

19" X 3.5" X 10.5"

My Signature 284 Amp came with an empty tube box. Where is the tube?

The empty box is the original box that the magic eye came in. The product manager thought that it would be a "cool" thing to include with the product.This has caused some confusion for a few customers. In the future, we will endeavour to have the documentation mention it.

Last reviewed: 8/8/00

Is there a European version of this amp that works at 220v and 50 hz?

Lexicon does not sell a 220V version of the Signature 284.  It will work with a stepdown transformer.

Last reviewed: 10/23/2000

If you set it up for distortion how do you get a clean sound?

If you set up the Signature 284 for max distortion with your guitar volume set to 10; rolling off your guitar volume to 7 will give you a nice clean sound without affecting the signal level coming out of the amplifier.

How wide should the eye be open on the Signature 284 Magic Eye Amplifier?

If you picture a circle and draw a wedge between 1 o'clock  and 11 o'clock that is how wide the eye will open. When the eye is totally closed it means the amp is maxed at 3 watts output.

Last reviewed: 3/3/99

How much power can the SB210 take? The SB210 has 2 x Mojo Tone 10" speakers.
They are rated at 8Ohms and 35 Watts peak per side.
How loud can the 284 sound with 3 watts?

The low power design is one of the main features that makes this a superb

recording amp and direct source. When connected to a recording or PA mixer,

loudness is determined at the console (fader settings, monitor send levels).

When connected to guitar cabinets, the loudness is, of course, determined by

the Left and Right Volume controls, but remember that, in the Signature 284,

these are also powerful tone controls. Turning up to get louder, will also change

the sonic character of the amp's tone.

When connected to guitar cabinets, you’ll find that the Signature 284 has plenty

of volume for home practice and recording overdubs. In fact, the essence of its

design is to deliver the great tone of an big amp cranked up, without the bone

crushing volume. This also means that, by itself, the Signature 284 cannot cover

live drums or most club situations.

For more volume, you have several options:

• Mike the cabs connected to the Signature 284.

• Use the slave outs to drive a separate power amp/guitar cab rig.

• Use the recording to provide a direct feed to the PA.

Examples of each of these options are detailed in the Applications section of

the User manual (PDF version included with this email).

Last reviewed: 9/25/00

How is the clean sound?

The Signature 284 can provide a nice clean tone which would not be considered thin.

Can you drive the Signature 284 with a preamp?


Last reviewed: 4/5/99

Can the Signature 284 be placed in-line prior to another amplifier?

Yes, the Signature 284 has a pair of Slave outputs for this application!

Is the Signature 284 adequate for steel guitar?


Is it possible to drive effects pedals/processors with the direct outputs of this unit?

Though it is possible to drive effects pedals or processors with the direct output of the Signature 284, the best results are achieved by plugging your guitar into the effects pedals and the output of the pedals to the input of the Signature 284.  Digital effects processors will be best utilized within the effects loop of the Signature 284.

Last reviewed: 8/3/99

How much power is provided by the Signature 284?

3 Watts per channel.

Can a transformer be bought for 220V operation?

You will not be able to make a 120V unit a 220V unit.  If you must use a 120V machine in a 220V situation you should use a stepdown transformer.

Last reviewed: 02/18/99

Can the switchable gain be changed with a footswitch on the Signature 284?

No, it is only selectable via the front panel.

Using the Signature 284 with MPX G2 and wanting to switch channels.

There are no channels to switch in the Signature 284.  What you can do is set your guitar volume to 10 and set up the Signature 284 for the most distortion that you want.  Back your guitar volume to 7 and you now have your clean sound.

Last Reviewed: 02/12/99

The Signature 284 emits a "howling" sound when the high gain is turned up.

A feature of an all tube preamp is that it provides harmonic distortion when the gain stage is pushed to a certain level.

Preamp bleed when not using the preamp of the Signature 284 while using the MPX G2.

Set SYSTEM: MODES: SEND BYPASS to Insert Mute in the MPX G2.

Last reviewed: 02/12/99

Outputs are overloading the inputs of a mixing console.

You should turn down the trim of your console or the output of the Signature 284, so that you are just below clipping with the loudest signal level that you would use.

How to properly gain stage the Signature 284 Recording Amp to minimize hum in recording applications.

It has been noted that in certain environments or applications, the Signature 284 Direct Recording Amp exhibits "hum". When properly gain-staged, the 284 is acceptably quiet. A method of accomplishing this is outlined below. Please note also that following these guidelines will in no way compromise the desirable "Class A" tone of the product.

This example uses the Mackie 1604. The same principles apply when using any other standard mixer. The key is to match the amp and mixer levels to allow you both plenty of signal and adequate headroom. The following outlines setting up a clean sound and then making adjustments to obtain that silky Class A distortion.

284 Set up:

- Plug your guitar into the input of the Signature 284.

- Connect one or both of the recording outs on the back of the 284 to channel inputs of your mixer. Note that the output of the 284 is pretty hot. If plugging into a Mic Preamp (or channel on a mixer which is a Mic preamp), the trim control (input gain) should be set all the way down. I personally run the 284 into a line input (NOT a Mic channel) and I have no level problems whatsoever.

- Turn on the amp, but leave the standby switch off.

- Working the controls left to right, make these settings:

- Gain - pushed in and set to 10:00

- Bass - 12:00

- Mid - 12:00

- Treble - 3:00

- Presence - 3:00

- Left and Right Masters - full up

Mixer set up:

For the sake of clarity, lets assume that you've plugged the 284 into mixer channels 1 and 2. Remember, if you're using mic inputs on these channels, the input trim must be set fully counter-clockwise. Start with  the main output faders (monitor level) all the way down. Bring the channel faders up about halfway (many boards have a center détente for the faders. If so, set the fader there at approx. halfway). Bring your main output fader(s) up as you strum your guitar (the guitars volume control should be full up) until the signal level on the LED ladder is hitting zero (roughly halfway).

You're there! At this point, you should have plenty of signal to record and if you can hear the hum at all, it should be very quiet (approx. 60dB under the guitar signal).

For distortion, increase the input gain knob on the 284 (and pull the knob out for really high gain stuff), backing off the 284 master volumes as you do. This will keep the overall level roughly consistent. If what you're after is both preamp and power amp distortion, bring both the input gain and masters on the 284 up as high as you wish - just lower the channel fader on the board as you do so. (This would actually decrease the hum even further).

It's important to keep in mind that guitar amps are inherently noisy. If one were to mic up an AC30 or Matchless, you would absolutely have quite a bit of noise along with your signal. The key is always to balance all the amplifier stages. Remember that (either with a 284 or micing a Marshall), you're running into at least 4 amplifiers: the guitar preamp, guitar power amp, mixer input channel and mixer summing amp (output stage). Proper gain staging must always be observed to obtain the quietest performance for any recording.

Happy Playing!

Last reviewed: 06/21/99

Problem: Is the Signature 284 too loud for home use.


Problem: Getting proper gain staging with a slave amp.

In order to get proper gain staging it is recommended that the slave amp has its own volume control.

Last reviewed: 7/19/99


Peerless Reviews

Signature 284 Guitar Amp Head

This is a wonderful sounding amp and there is nothing else like it on the market. It really does put out good tone at low volume. Please see my comments on Lexicon support.

Very feature rich. Two rack space stereo EL84 (fan cooled!)tube driven amp with detachable AC and all the connectivity options you'll ever need: stereo effects loop, slave outs, direct outs with 2x12 or 2x10 cabinet emulation, XLR outs, and 4 or 8 ohm outs. The effects loops are tube driven. Preamp section consists of a 3band eq and preamp gain with push-pull for extra gain. There are also two power amp volume controls that allow you to individually control the amount of power tube saturation of each side. Thus you have the option of preamp distortion, poweramp distortion or both. It's a Class A amp.

Sound Quality: 8

I've played the Signature 284 through two strats, a humbucker equiped LoneStar and a 1960 Custom Shop Closet Classic, and a Carvin DC127 with superdistortion pickups and active electronics. I'm using various floor effects and for a while I used the Lexicon MPXG2 guitar processor. I usually use a Mesa 2x12 with Vintage30's with this amp.

The clean sound of this amp is awesome. I get a lot of low end and rolled off highs from the Boogie cabinet but if I put one side of the amp through the speaker input of a Fender Princeton Reverb cabinet (w/ a Weber C10Q) the 284 sounds just like my Fender amps. So, if your lusting after the Fender clean tone just know that I can't distinguish this amp from a Fender on tape. I thought the hi gain texture was a little different, a bit more modern sounding, tighter with more crunch. I experimented with the preamp tubes (changed to Mullards which I keep in most of my Fender amps) and I then found that the 284 warmed up quite a bit and the overdrive became much smoother, again just like a Fender. However, this amp is much more versatile than a Fender with plenty of hi gain when using the push/pull knob and the bottom end stays nice and tight due to the solid state rectifier. The power section, preamp gain, tone stacks, and effects loop are all tube driven so like true audiophile equipment you can get all kinds of tonal differences by changing the tubes. The only problem with the sound of this amp is that when the extra gain stage is engaged by pulling the gain knob out, the bottom end loosens when the gain is dialed past 12 o'clock. This amp uses Sovtek El84 power tubes and a flabby bottom is a characteristic of these tubes. I wanted to write the review after experimenting more with different power tubes but my experience with Lexicon support encouraged me to go ahead and spit this out to help/warn/inform any of you out there. The flabby bottom when using tons of distortion isn't such a problem when I have hot pickups in the guitar. That is, I can get a lot of preamp saturation without going to far, but if I'm playing a strat and I want a lot of distortion, I fall back on a pedal. This amp is virtually noiseless except when the pull gain stage is used and is cranked! Again, I found the level of this hiss to be a function of the type/quality of 12AX7 I am using. Overall it's quiter than most amps, hell it's only 6 watts per side.

This brings me to what I like the best about this amp: the cranked tube tone at low volume. I don't guess there is too much of a mystery on how it's done: it's class A which sounds better at lower power, it has great direct control of the amount of tube saturation with out greatly effecting the overall volume, and it's only 6 watts per side. I can hear the guitar tone swell and blossom with rich, blah, blah, blah.. That is too say I can make it sound like a cranked Marshall in a outside venue. Excellent tube tone! If I want tighter distortion I can simply roll the volumes back to 2 and crank the preamp gain. With the preamp and tube amp levels in the middle this things sounds like a Marshall JCM800 (just like it says in the suggested settings) but I can always dial in the before mentioned Fender tones. These are just comparisons using my ears, this is an amp with it's own voice not an amp emulator. Speaking of which, if you use a POD, you'll love how it sounds through the receive of the effects loop (GT5 also). You can take advantage of the stereo capabilities to run two guitars at once through different sides or mix wet and dry signals (all via the effects loop).

Reliability: 9

I removed the cover and I was a little concerned about some aspects of the construction. If you ever drop this thing, it may be over. It's a tube amp in a rack unit so you need to be a little careful. Most of the wiring is excellent and as far as I can tell high quality components were used. For instance, the tube sockets are porcelain which you usually only see on boutique amps! The wiring is very neat and all the tube sockets and pots are seperated off the PCB. Almost a point to point/PCB hybrid like MesaBoogie uses without so many cheap ribbon cables. The PCB contrunction is very well laid out and labeled thus making this amp easy to figure out and yes, even modify! Oh and the tubes are mounted sidewise and held in place with fasteners. There is a fan to cool things and it is noisless. I was surprised to find NOS tubes in the preamp section. Again the power tubes are Sovtek EL84's, nonmilitary issue. These tubes sound better than the milspecs but these are the tubes that Vox amps eat up in a matter of hours. I used this amp a good bit over the last few months and have had no problems. The power rating for this amp is so low that they will probably last a good while. NOS EL84's would last forever and undoubtedly make this amp sound even better. If you can't justify the extra expense of NOS I would suggest Electroharmonix EL84's.

Customer Support: 1

This amp is readily modifiable so I called Lexicon for a schematic. Also, I noticed that one of the 12AX7 slots was occupied by a 12AT7 and there is sometimes a good reason for making this substitution depending on the circuit characteristics. Otherwise, this substitution can harm the amps tone! The customer support representative at Lexicon refused to send me a schematic. I asked if he would simply tell me which Fender circuit the amp was based on and he flatly stated that that information is not for public consumption. If you know anything about the history of tube amplification from RCA's original schematic sold with their power tubes which evolved into Fender which eventually yielded both Marshall and Mesaboogie, you know how ridiculous this is. Also, many techs would be hard pressed to service and replace parts in an amp without the schematic. I placed a seaperate call to inquire about the tube substitution and spoke with a different representative. He said the amp was "supposed" to have the 12AT7. Then he admitted that he did not know the difference between a 12AX7 and a 12AT7. I made sure I was actually speaking with a support guy for the Lexicon 284 (yeah right). I was again refused a schematic even though noone at Lexicon could answer the simplest of questions. Especially one that could be answered with the blueprint in front of you. I politely pressed the ridiculousness of the situation and I was told to call the Lace people at Lace Music with my querry. Who is Lace Music? They are the folks that actually made the amp for Lexicon. I talked with someone on the phone there who was very helpful. It turns out the amp is based on a Fender circuit but he couldn't remember which one. The 12AT7 was used because of the shortage of good 12AX7's but also depends on the tone of the EQ voicing sought after. A 12AT7 makes the EQ section less responsive but warms up overall tone. I got my freakin' schematic! I was told that he had sent 100 over to Lexicon to give out to the public and didn't understand why they refuse to do so. Lexicon doesn't even own the rights to the amp, they just distribute it. Further, Lexicon has stopped distributing the 284 thus dropping the ball on Lace Music and sticking them with parts for over 300 amps yet to be made. Lace is looking for a new distributor and I was told that talk is under way with at least one huge name in the amp world (I bet you can guess who!).

Just thought you might find this information usful because we are consumers and so we have the chance to vote every day. This is my second negative dealing with Lexicon, and I have read about others here on HC. I'm pretty sure Lexicon is an alternate spelling for moron. Between this and my experience with the MPXG2, I'm sure that reverb is the only thing they do well.

Overall, I am very pleased with the sound quality and construction quality of this amp. I am disappointed that more of them are not out there but Lexicon doesn't advertise it. Whatever, I got mine! If this amp is picked up by another distributor things could really take off. The EL84's sound Fendery clean but have an edgier overdriven tone. The connectivity makes it very versatile and good for most any studio application. I get a lot of different sounds by switching cabinets and speakers with this head. The only problem is the bottom end gets a bit flabby when pushing the amp really hard.