Burn Unit II vs. Burn Unit EQ

[drmathprog]

Are there any difference between these two versions of the Burn Unit other than that the II has a single internal trim control while the EQ has three internal trim controls?

[David Barber]

Are there any difference between these two versions of the Burn Unit other than that the II has a single internal trim control while the EQ has three internal trim controls?

This is always a funny question to answer, we never made a Burn Unit II, but I usually assume it is the name players gave to the Burn Unit in the dual stomp format. The Burn Unit EQ has the extra internal trimmers for adjusting the Barber RIAA style recovery circuit. The big addition is bass, mids and presence. The EQ model can get back to the older BU sound simply by turning the presence off and bass off, then use the mid control for all internal tweaking.

[codster]

Dave would you explain the RIAA circuit for us.

[drmathprog]

So I take it the the Burn EQ soounds different than the previous version unless it is specifically tweaked to sound the same?
How long ago did you make the switch from regular Burn to Burn EQ?

[David Barber]

Dave would you explain the RIAA circuit for us.

Take a look at the recovery stage of the Silver LTD and you get the basic idea. I created an adjustable RIAA circuit to adjust bass and midrange levels in Barber pedals, I custom tune the circuit for each Barber pedal (cab and trimmer values). The basic idea comes from the RIAA phonograph preamp circuits that were used with magnetic phono cartridges. I tuned it for overdrive recovery and added adjustability. When processing distorted guitar tones, you often need to trim bass to keep things "smooth and tight", for years pedal builders just left out the bass after it was trimmed, and gave you midrange boost plus distortion (TS), I added the Barber RIAA style circuit as a recovery stage like vinyl used to bring bass back to proper levels, this allows a nice mirror of the input, and does not require the high amp volume that most contemporary pedals need to sound good.

Here is a link to the Silver LTD schematic:

http://www.barberelectronics.com/Barber ... s_DIY.html

[drmathprog]

So I take it the the Burn EQ soounds different than the previous version unless it is specifically tweaked to sound the same?
How long ago did you make the switch from regular Burn to Burn EQ?

Bump?

[David Barber]

So I take it the the Burn EQ soounds different than the previous version unless it is specifically tweaked to sound the same?
How long ago did you make the switch from regular Burn to Burn EQ?

Bump?

Indeed, the switch was around 2002 I think.

[drmathprog]

Can you elaborate? Does the Earlier Burn Unit not have the RIAA circuit, or does it have one but with only a single bass trim control?

[David Barber]

Can you elaborate? Does the Earlier Burn Unit not have the RIAA circuit, or does it have one but with only a single bass trim control?

The early Burn Unit (single and dual) has a single trim for low mid/bass, just a cap across a trimmer in the feedback loop, simple but effective.

[ToneGrail]

Dave,

Is there an easy way to upgrade the Dual Burn Unit to the Burn Unit EQ either by a mod or an exchange?