Vacuum Tube - KT88, JJ Electronics

Vacuum Tube - KT88, JJ Electronics

JJ Electronics
Vacuum Tube - KT88, JJ Electronics image 1
Vacuum Tube - KT88, JJ Electronics image 2
Customer image:<br/>"My Dynakit Mark III getting new J/J KT88s and a general check over."
Customer image:<br/>"JJ Electronics KT88 in Willsenton R8"
Customer image:<br/>""
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Vacuum Tube - KT88, JJ Electronics image 1Vacuum Tube - KT88, JJ Electronics image 2
Customer Images:
Customer image: "My Dynakit Mark III getting new J/J KT88s and a general check over."Customer image: "JJ Electronics KT88 in Willsenton R8"Customer image: ""
Starting at: $39.95
In Stock

The JJ Electronic KT88 is a sonically faithful reproduction of the original tubes with a robust construction encased in a thick glass envelope. The JJ KT88 delivers a powerful 42 Watts with plenty of headroom to spare. This tube has a tone that is warm and lively with a detailed and balance response. The JJ KT88 is an excellent choice for Hi-Fi stereo equipment as well as guitar amplifiers. It can be used in place of 6550 tubes.

Apex Tube Matching
Matched versions of this tube use Apex Matching
RoHS Compliant
SKU:
T-KT88-JJ
Item ID:
004876
Brand:
JJ Electronics, Apex Matched
Type:
Part Numbers
Single or MatchedOur Part NumberUPC/EANJJ Electronics Part Number
Apex Matched PairT-KT88-JJ-MP609722123235
Apex Matched QuadT-KT88-JJ-MQ609722123242
Apex Matched SextetT-KT88-JJ-MS609722123259
SingleT-KT88-JJ609722123228 KT88
Product Measurements by Type
Body Height110 mm
Cathode Current (Ik)≤ 230 mA
Filament Current (If)1.6 A
Filament Voltage (Uf)6.3 V
Gain (μ)8
Grid 1 voltage (Ug1)-15 V typical
Grid 2 current (Ig2)≤ 7 mA
Grid 2 dissipation (Wg2)8 W
Grid 2 voltage (Ug2)≤ 600 V, 250 V typical
Grid capacitance (cg1)16.5 pF
Grid to Plate Capacitance (ca/g)2.3 pF
Internal Resistance (Ri)12 kΩ
Item Diameter52 mm
Item Height125 mm
Plate Capacitance (ca)10 pF
Plate Current (Ia)140 mA
Plate Dissipation (Wa)≤ 42 W
Plate Voltage (Ua)≤ 800 V, 250 V typical
Transconductance (S)11.5 mA/V
Packaging Information
Packaging DimensionsApex Matched Pair versionT-KT88-JJ-MP5.3 in. × 4.5 in. × 2.3 in.
Apex Matched Quad versionT-KT88-JJ-MQ5.3 in. × 4.5 in. × 4.5 in.
Apex Matched Sextet versionT-KT88-JJ-MS6.8 in. × 5.3 in. × 4.5 in.
Single versionT-KT88-JJ2.3 in. × 2.3 in. × 5.1 in.
Weight (Packaging)Apex Matched Pair versionT-KT88-JJ-MP0.54 lbs.
Apex Matched Quad versionT-KT88-JJ-MQ1.08 lbs.
Apex Matched Sextet versionT-KT88-JJ-MS1.62 lbs.
Single versionT-KT88-JJ0.27 lbs.
Product Measurements by Item
T-KT88-JJ-MP - Apex Matched Pair versionBody Height110 mm
Cathode Current (Ik)≤ 230 mA
Filament Current (If)1.6 A
Filament Voltage (Uf)6.3 V
Gain (μ)8
Grid 1 voltage (Ug1)-15 V typical
Grid 2 current (Ig2)≤ 7 mA
Grid 2 dissipation (Wg2)8 W
Grid 2 voltage (Ug2)≤ 600 V, 250 V typical
Grid capacitance (cg1)16.5 pF
Grid to Plate Capacitance (ca/g)2.3 pF
Internal Resistance (Ri)12 kΩ
Item Diameter52 mm
Item Height125 mm
Plate Capacitance (ca)10 pF
Plate Current (Ia)140 mA
Plate Dissipation (Wa)≤ 42 W
Plate Voltage (Ua)≤ 800 V, 250 V typical
Transconductance (S)11.5 mA/V
T-KT88-JJ-MQ - Apex Matched Quad versionBody Height110 mm
Cathode Current (Ik)≤ 230 mA
Filament Current (If)1.6 A
Filament Voltage (Uf)6.3 V
Gain (μ)8
Grid 1 voltage (Ug1)-15 V typical
Grid 2 current (Ig2)≤ 7 mA
Grid 2 dissipation (Wg2)8 W
Grid 2 voltage (Ug2)≤ 600 V, 250 V typical
Grid capacitance (cg1)16.5 pF
Grid to Plate Capacitance (ca/g)2.3 pF
Internal Resistance (Ri)12 kΩ
Item Diameter52 mm
Item Height125 mm
Plate Capacitance (ca)10 pF
Plate Current (Ia)140 mA
Plate Dissipation (Wa)≤ 42 W
Plate Voltage (Ua)≤ 800 V, 250 V typical
Transconductance (S)11.5 mA/V
T-KT88-JJ-MS - Apex Matched Sextet versionBody Height110 mm
Cathode Current (Ik)≤ 230 mA
Filament Current (If)1.6 A
Filament Voltage (Uf)6.3 V
Gain (μ)8
Grid 1 voltage (Ug1)-15 V typical
Grid 2 current (Ig2)≤ 7 mA
Grid 2 dissipation (Wg2)8 W
Grid 2 voltage (Ug2)≤ 600 V, 250 V typical
Grid capacitance (cg1)16.5 pF
Grid to Plate Capacitance (ca/g)2.3 pF
Internal Resistance (Ri)12 kΩ
Item Diameter52 mm
Item Height125 mm
Plate Capacitance (ca)10 pF
Plate Current (Ia)140 mA
Plate Dissipation (Wa)≤ 42 W
Plate Voltage (Ua)≤ 800 V, 250 V typical
Transconductance (S)11.5 mA/V
T-KT88-JJ - Single versionBody Height110 mm
Cathode Current (Ik)≤ 230 mA
Filament Current (If)1.6 A
Filament Voltage (Uf)6.3 V
Gain (μ)8
Grid 1 voltage (Ug1)-15 V typical
Grid 2 current (Ig2)≤ 7 mA
Grid 2 dissipation (Wg2)8 W
Grid 2 voltage (Ug2)≤ 600 V, 250 V typical
Grid capacitance (cg1)16.5 pF
Grid to Plate Capacitance (ca/g)2.3 pF
Internal Resistance (Ri)12 kΩ
Item Diameter52 mm
Item Height125 mm
Plate Capacitance (ca)10 pF
Plate Current (Ia)140 mA
Plate Dissipation (Wa)≤ 42 W
Plate Voltage (Ua)≤ 800 V, 250 V typical
Transconductance (S)11.5 mA/V

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Specifications, Files, and Documents

PDF: Specification Sheet Specification Sheet504.71 KB

Questions and Answers

Click each question to see its answers.
Asked by Anonymous on May 21st, 2016.
JustinG
May 23rd, 2016
Staff Member
Top Contributor
The KT88's are similar in construction and power to the 6550's but they may not be drop in replacements depending on the unit. I would suggest referencing the spec sheet for both found on the product pages for absolute compatibility.
Asked by Anonymous on May 26th, 2017.
Matt H.
May 26th, 2017
Staff Member
The KT 77 and 88 will give you more lows but not necessarily less highs. Our experience has been that swapping preamp tubes has more of an effect on the high end than the power tubes. Also, if you have an older bivalve the KT88's will be to big for the top to fit.

Product Reviews

4.82 out of 5 based on 11 reviews
- June 3rd, 2021
5 out of 5

I inserted them in the sockets of my Sunn 200S adjusted the bias and the amp is alive.

- February 26th, 2021
4 out of 5

Brought a much warmer sound to the entire frequency range in my Willsenton R8. A must have upgrade to this amplifier. Great value from a great vendor that appreciates their customers and is focused on customer service. Thanks.

- May 15th, 2020
5 out of 5

I've been using J/J tubes since they first became available. I use them in my own gear and the gear I service. Only 2 tubes had to be replaced in all that time. They work well and can take the abuse of guitar amplifiers on the road.

- December 29th, 2019
5 out of 5

Quick delivery and great tubes.
Thank you.

- May 3rd, 2019
5 out of 5

These are great tubes for my Leslie 122. Great sound, nice drive. Works as a modern replacement for these amps.

- January 19th, 2019
5 out of 5

I have heard about the kt88,but I never tried them. So I brought these tubes and man I never go back to the 6550 power amp tubes.gives you all the lows you need. I use them in my 122 Leslie speaker,

- July 10th, 2018
5 out of 5

Lovely tubes. Solid construction. Typical KT88 sound, as it should be.

- April 2nd, 2016
5 out of 5

I've tried more than a dozen power tubes in my Amps &* Sound Mogwai headphone/speaker amplifier. I checked out a variety of KT88, 6L6, 6CA7, 6550, 5881, and similar tubes.

The JJ KT88 are excellent tubes. They have great bass, smooth treble, and very nice full mids.

Unlike most KT88 tubes, they have virtually no microphonics at all.

The sound, availability, price, ability to get Apex-matched tubes, and robust build quality pushed me to make this my house tube.

Other tubes I put them up against:

Mullard KT88 (New and NOS)
Svetlana 6550 Winged C (New and NOS)
6P3S (NOS)
Svetlana 6550 (New)
Preferred Series KT88 (New)
JJ 6CA7 (New)
Sovtek 5881WGC (New)
5881 Tung-Sol (New)
Tung-Sol 6L6GC-STR (New)
Electro-Harmonix KT88 (New)
Electro-Harmonix EL34 (New)
Electro-Harmonix 6550 (New)

- January 17th, 2016
5 out of 5

As far as I can tell, these tubes are visually and sonically identical to the OEM branded KT88s that came in my McIntosh MC275mkVI. I tried to replace them with the Russian Gold Lion reissues and much prefer the JJs in this amp. The Gold Lions were crispier and tighter, but thinner sounding and too aggressive in the high mids and low treble. The JJs are easier on the ears. The bass is especially nice.

- January 8th, 2015
5 out of 5

These tube, related to the build, are massive, strong,heavy.
On My Chinese amp (Yaqin MS110 b) sounds a bit less "tube" than the Chinese one, more "KSSSSS".
After adjusting the bias, at 0.5 V, that was the bias of shuguang tubes, these ones let the amp drastically less hot...
Before, with shuguang tubes my amps was difficult to touch after an hour, now with these tubes, after two hours, transformers are just more than tempered...

Substitute Products

The following items can be substituted for this product. While not necessarily exactly the same, they will function as replacement items in your project.