Electro-Harmonix 6CA7EH Power Vacuum Tube (Matched)
Need matched power tubes? Don't worry! Price includes matching in any quantity you need for no extra charge. Need a matched pair? Just order "2" tubes. For a matched quad order "4" tubes. Matched sextets and octets are available as well.The Electro Harmonix 6CA7-EH power vacuum tube has been available for nearly 20 years. This power tube is a tribute to the legendary USA made Sylvania/Philips 6CA7 tube, with its fat-bottle and sturdy plate.
This 6CA7 vacuum tube can be used in nearly any EL34 tube amplifier, and is considered a drop-in replacement. However, it does have different bias voltage requirements than most EL34 vacuum tubes. We find often an increase of about 30-50% more bias voltage is needed to operate the 6CA7 appropriately. If you're not sure if your tube amplifier is compatible check with us or a technician you trust. If you're amp's stock bias range can't dial them in, usually a simple resistor change is all that's needed.
The history of the 6CA7 is quite interesting. Eric Barbour's article (Senior Editor, VTV Magazine 2001) has a good summary of how it began. In the very late 1960's, Sylvania "took a 6550 structure and changed the grids, so the tube biased like an EL34." Simply, Sylvania wanted something to compete with the popular British Mullard EL34 at that time. So in technical terms it is actually a tetrode and does have more of a 6550 tube sound characteristic because of it. Normal EL34 tube types are pentodes. Eric mentions the reason for why EL34 sound so different from 6550, 6L6, KT77, etc is because at the time they were considered a lower cost option with a softer vacuum than the 6CA7 and 6550 tubes. This leads to them being easier to drive, and having smoother overdrive, than 6L6 and 6550, especially when really pushing them in a tube guitar amp.
Other Electro-Harmonix tubes
EL34 Tube TypesAdditional Information and Downloads
Reviews:
EL34 Tube Review
Tube Matching Information:
Power Tube Matching FAQ
Perfect Pair System
Downloads:
Electro-Harmonix 6CA7EH Datasheet (PDF)
Download Adobe Acrobat PDF reader
Warranty Information and Return Policy
Warranty Period: 3 monthsAll our tubes are guaranteed for 3 months from the date of purchase. (Any exceptions will be noted on that tube's Warranty tab)
If you receive a tube that does not perform to the manufacturer's specifications, please do the following:
- contact us to get a return authorization
- return it via regular mail within 90 days from when we shipped it, and we will provide an exchange or refund of the full purchase price of the tube.
Returns not related to warranty or defect will be considered at our discretion, and are subject to a 15% restocking fee.
We can not accept returns that don't have an authorization, are past 3 month, or are returned improperly.
These guidelines may be updated without notice.
Ratings & Reviews
16 reviews
Electro-Harmonix 6CA7EH | HiFi
by David
These EH-6CA7 tubes are remarkable for money and last a long time.
It should be noted that although they work well in an amplifier designed for EL34's they are constructed differently.
I like them
Davir
Amazing sound
by Kevin
So I put four balanced 12ax7’s two 6ca7’s and two 6l6gc all from EH in my Bugera 333xl infinium and HOLY CRAP!!! I play mainly hard rock/metal and I’ve never had more crunch and amazing cleans it’s not even the same amp anymore I was able to completely ditch my ts9 boost pedal it doesn’t even come close to needing it. Thank you EH for such awesome tubes.
Fantastic EL34
by B. H. de C.
I used this tubes in 2 different amplifiers with fantastic results. They are very robust tubes and can take a lot of abuse. They sound very detailed and dynamic. This is my preferred EL34 tube. I now use those instead of a Gold Lion KT77
EL34 on steroids?
by Steve
I put a pair of these in my 1st generation Traynor Bass - Master and they perform great!
Clean, bold, and where it used to give about 40 watts, the amp's now giving a solid 50W. The plates are big compared with a regular EL34 and they sure look like they can handle more than other EL34 / 6CA7's, but just setting the old Traynor to a pretty comfortable bias point delivered the sound I want.
Close on the heels of my RCAs
by Bob
This will be a short review and more like briefing. That said, this is what I discovered tonight. I have a quad of RCA 6CA7 tubes that are NOS from the early 1960's. I played the RCA tubes tonight for the first time in my Jolida amp. I have used the EH 6CA7 tubes in this amp before so I am very familiar with the sonic character of the tube. Well, I was quite surprised when I listened to the RCA tubes and compared to the EH tubes. I would say that the EH tubes give me about 85% of what the RCA tubes do. No some might not think 85% is a lot, but comparing price and availability of the EH tubes to NOS RCA tubes, that remaining 15% gets smaller. The RCA tubes sound a little richer, more full bodied, and has a touch more "presence" but I had to listen pretty close to get that. As I said, the EH tubes will give you real good idea of what a RCA 6CA7 from 1962 sounds like.
Sorry - I guess this wasn't that short after all.