The Ibanez ST9 Super Tube Screamer is an overdrive pedal from 1983, a variant of the Tube Screamer family built by Maxon for Ibanez. Its distinguishing feature is a fourth control, a Mid Boost pot, added to the usual Tube Screamer arrangement. Premier Guitar's history of the Tube Screamer describes it as a Mid Boost control added to the design, briefly available in Europe but never in the US, and extremely rare1. TONEHOME calls the ST9 "the culmination of the Tubescreamer"2.
What the Mid Boost stage does
A standard Tube Screamer such as the TS9 carries three knobs. The ST9 adds a fourth. TONEHOME explains that "a fourth pot for Mid Boost is introduced to improve tonality control"2, and Premier Guitar lists the knob configuration as Overdrive, Mid Boost, Tone and Level1.
| Control | What it does |
|---|---|
| Overdrive | The usual Tube Screamer drive control1 |
| Mid Boost | Added fourth pot for midrange control, placed before the clipping stage2 |
| Tone | The usual Tube Screamer tone control1 |
| Level | The usual Tube Screamer output level control1 |
Aion FX describes the circuit as "essentially a stock Tube Screamer with an added stage, a semi-parametric midrange control that delivers a fixed boost"3. Where that stage sits in the signal path matters. Analog Man's Mike Piera writes that these pedals "are like a Tube Screamer with an added MIDS control, which is before clipping on the ST-9 and after the clipping stage" in the related STL version5. Aion FX adds that "most people who have played both versions prefer the ST-9's pre-clipping boost because of the way it affects the clipping"3.
"a fourth pot for Mid Boost is introduced to improve tonality control"
On the component level, the ST9 differs from the TS9 in its chips and its control layout21:
| Ibanez ST9 | Ibanez TS9 | |
|---|---|---|
| Controls | Overdrive, Mid Boost, Tone, Level1 | Overdrive, Tone, Level1 |
| Op-amp chips | Two JRC4558D IC chips2 | One JRC4558D IC chip2 |
| Mid Boost stage | Yes, before clipping2 | No |
| Production run | 1983 to 1984, very small quantities3 | Longer production run3 |
As for sound, TONEHOME describes it as "similar to the TS9, but delivering more sustain and drive"2.
A short production run, sold only in Europe
The ST9 was made in very small quantities and sold only in Europe between 1983 and 1984, according to Aion FX3. Premier Guitar's review of Maxon's later reissue notes the original "was manufactured by Maxon for Ibanez in very limited numbers"4. Analog Man's Tube Screamer history agrees that it "seems to have been sold only in Europe"5, and adds that these pedals "are very rare and mostly found in Europe"6.
Aion FX reports the pedal was also available inside Japan under the Maxon brand name, and that even fewer of those exist3. US players never saw it new: Premier Guitar's history records it as briefly available in Europe but not in the US1.
TONEHOME lists the 1984 list price as 190 DM2, a German mark figure from the period.
Never reissued, but the circuit returned
TONEHOME records the Ibanez ST9 as never reissued2. The circuit itself, though, came back: Aion FX notes that "in the last couple of years the Super Tube Screamer was reissued by Maxon as the ST9 Pro+" and that this reissue has not been traced by circuit analysts3.
For collectors, TONEHOME rates the ST9's collectibility as extremely high2. The combination explains why:
- A brief 1983 to 1984 production run3
- Very small quantities built3
- European-only distribution, with a small number in Japan under the Maxon name3
- No Ibanez reissue2
Players interested in the wider family can compare it with the TS808, the TS10 Tube Screamer Classic, or the Nu Tube Screamer, or read more on the overdrive type page.
Videos
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Guitar & Bass Breakdown
Questions
How is the Ibanez ST9 different from the TS9?
The ST9 is essentially a Tube Screamer with an added fourth control, a Mid Boost pot, alongside the usual Overdrive, Tone and Level knobs. It uses two JRC4558D IC chips instead of the single chip in the TS9, and TONEHOME describes its sound as similar to the TS9 but delivering more sustain and drive. The Mid Boost stage sits before the clipping stage, which is the change most players point to.
Was the ST9 Super Tube Screamer sold in the US?
No. According to Premier Guitar's Tube Screamer history, the ST9 was briefly available in Europe but not in the US. Aion FX adds that it was made in very small quantities and sold only in Europe between 1983 and 1984, with a small number also sold in Japan under the Maxon brand name.
Has the Ibanez ST9 been reissued?
TONEHOME records the original Ibanez ST9 as never reissued. However, Maxon has reissued the Super Tube Screamer circuit itself as the ST9 Pro+, a pedal Aion FX notes has not yet been fully traced by circuit analysts.
Why is the ST9 so collectible?
TONEHOME rates its collectibility as extremely high. It was produced only briefly, in very small numbers, sold almost entirely in Europe, and was never reissued under the Ibanez name. Analog Man notes these pedals are very rare and mostly found in Europe, which keeps supply far below demand among Tube Screamer collectors.
How many op-amp chips does the ST9 have?
Two. TONEHOME reports the ST9 carries two JRC4558D IC chips instead of the one found in the TS9, the extra chip serving the added Mid Boost stage.
Sources (6)
- Green Giant: History of the Tube Screamer, Premier Guitar (www.premierguitar.com), 2011-10-18
- TONEHOME, TONEHOME, 1984
- Cirrus Dynamic Overdrive / Ibanez® ST-9, Aion FX, 2021-03-19
- Maxon ST-9 Pro+ Super Tube Pedal Review, Premier Guitar, 2010-10-20
- Ibanez Tube Screamer History, analogman.com, 2023
- Analog Man Tube Screamer Collection, analogman.com, 2015
