Mark V 90: no bass response?

The Boogie Board

Help Support The Boogie Board:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

dsky17

Member
Joined
Oct 28, 2019
Messages
9
Reaction score
0
Hey guys! Purchased a new Mk V 90 head a few weeks ago, and am playing it through a well-broken in 2x12 Recto Slant cab. When playing Channel 3 in either IIC+ or IV mode, no matter what I seem to do, they both almost completely lack bass response, ie: almost no full bass you can hear, or even better described: no bass you can FEEL. On the Extreme mode, the bass THUMPS, even at the super low volumes. Even when I do crank the volume up to tolerable-without-earplug levels, there's just no bass you can really feel even when chugging on a palm muted low E string on the IIC+ or IV modes.

To describe it differently, on Extreme mode it sounds 'normal', like all frequencies are being heard. On the IIC+ and IV modes, it's almost as if the sound is being run through a hi-pass filter, only allowing the mid and treble frequencies to be openly heard & felt. It's almost that extreme. And I didn't notice it for the first couple weeks when I received it because I was so hyper-focused on getting the IIC+ and IV modes setup that I barely touched the Extreme mode until two weeks ago, but when I did - BAM - there was the bass response. Night and day difference. I know the Extreme mode has more bass than the other modes, but it's not simply that the Extreme mode has more bass. IIC+ and IV modes just don't seem right. Those two modes have been virtually unplayable because of the lack of full frequency (specifically low end) response.

I never had the opportunity to play a Mark V before ordering mine, so I have no other Mk Vs to compare it to, but I've never experienced this with any other amp. The bass knob is around 9 o'clock, as even though there's no bass response it still flubs out any higher than that with the gain past 12. The EQ is setup pretty much as a typical V, and I've tried the exact settings Petrucci describes in his tone settings video walkthroughs as well. Flipped every switch and turned every knob to virtually every imaginable setting combination. Cannot figure it out!

I got in contact with Mesa today about it - they were extremely responsive and I'm sure they'll be extremely helpful as they're the experts, but I just wanted to see if anyone else has ever had this issue, and if so have any idea what could be the problem? Is this somehow normal? Any thoughts/ideas/suggestions would be greatly appreciated.

Want to love this thing....spent a looong time debating between the MkV and JP2C, and went with the V for the versatility. Really hoping I didn't make the wrong choice! Thanks in advance for any advice!

Cheers!
 
APEMAN said:
This sounds typical to me - you should try the saturation mod (12AT7 in v4 and/or v6, as you like). Next to the more elastic overtone feel comes the ability to open up the presence, which will result in a better bass response.

The IIC+ mode is given in the 'non-deep' configuration.

The IV mode is given in the 'deep' configuration featuring more bass (and unfortunately more ice pick as well).

The extreme mode uses the IIC+ mode (not the IV mode as stated in the manual!) in 'deep' configuration with reduced negative feedback. (This is the most unique MarkV sound in CH3 as this configuration can not be found on any previous Mark).

The MarkV is modeled after dough wests favorite MarkIIC+ / it is not intended to be a hardcore metal amp.

To be honest, I was never really happy with the tones from CH3, which led me to hard modding the modes on my amp's CH3 to my liking. Now, that thing breathes fire simply by restoring the original Mark circuitry. I think I should record another video to show what this amp - as a mod basis - can do.

Thanks so much for the response and info! Interesting that you said Extreme mode is IIC+, not IV as stated in the manual, as I thought it had a more IIC+ quality of gain & tone. It seems insane to me that these issues are "normal" for the Mark V, but with the seemingly overwhelming success of the saturation mod, hopefully that's the ticket. That thread was an awesome read btw - I'd found it previously but gave it a solid read through this morning.

Would you mind sharing a link(s) to which 12AT7 you'd recommend purchasing (in the US)? Are either of these recommended?:

https://tubedepot.com/products/early-1950-s-jg-ge-12at7-military-stock
https://tubedepot.com/products/12at7wc-jan-philips

I read some people are using Mesa 12AT7 and seem satisfied as well it seems?

Thanks again!
 
Hi

Agree to APEMAN’s point - the Mark V c+ mode was modelled off the non-GEQ c+ which had a smaller cap at the end of the circuit. This acts as a high pass filter so it naturally does not have a lot of bass. The GEQ can be used more aggressively to compensate. The IV mode has the larger cap if I recall which adds bass response plus as APEMAN mentioned also has PULL DEEP and BRIGHT active. So I’m a little surprised you don’t hear bass in the IV mode. There’s usually a noticeable difference between c+ and IV in both sound and feel. I do think the pull functions for pull deep and bright (all of them actually) have been made far less dramatic in the V and JP compared to the original c+. Since the Mark IV actually.

The extreme adds the thump because of the changes in the power amp similar to the Mark IV push presence. I was under the impression the IV mode is a IV circuit with presence pulled and Extreme is IV circuit with presence knob pushed. To me when I A/B them they sound almost identical but for inherent differences in level of saturation for the newer amps.

I run the bass fader on the GEQ for c+ and IV fairly high. For thump I use crunch mode with unconventional settings settings (Max Gain and Treble, Bass around 10:30-11) and it has a tonne of body. I’ve recently started using Extreme with bass around 11 which gets a rectifier style sound as well.

The JP has around as much bass as the IV mode (maybe a tad more) presuming there are no issues with your V but it sounds thicker than the c+ mode. I expect this is due to pull deep, huge transformer and different power amp.

Had you played a mark amp before?

What settings do you use (controls & GEQ)?
 
dsky17 said:
APEMAN said:
This sounds typical to me - you should try the saturation mod (12AT7 in v4 and/or v6, as you like). Next to the more elastic overtone feel comes the ability to open up the presence, which will result in a better bass response.

The IIC+ mode is given in the 'non-deep' configuration.

The IV mode is given in the 'deep' configuration featuring more bass (and unfortunately more ice pick as well).

The extreme mode uses the IIC+ mode (not the IV mode as stated in the manual!) in 'deep' configuration with reduced negative feedback. (This is the most unique MarkV sound in CH3 as this configuration can not be found on any previous Mark).

The MarkV is modeled after dough wests favorite MarkIIC+ / it is not intended to be a hardcore metal amp.

To be honest, I was never really happy with the tones from CH3, which led me to hard modding the modes on my amp's CH3 to my liking. Now, that thing breathes fire simply by restoring the original Mark circuitry. I think I should record another video to show what this amp - as a mod basis - can do.

Thanks so much for the response and info! Interesting that you said Extreme mode is IIC+, not IV as stated in the manual, as I thought it had a more IIC+ quality of gain & tone. It seems insane to me that these issues are "normal" for the Mark V, but with the seemingly overwhelming success of the saturation mod, hopefully that's the ticket. That thread was an awesome read btw - I'd found it previously but gave it a solid read through this morning.

Would you mind sharing a link(s) to which 12AT7 you'd recommend purchasing (in the US)? Are either of these recommended?:

https://tubedepot.com/products/early-1950-s-jg-ge-12at7-military-stock
https://tubedepot.com/products/12at7wc-jan-philips

I read some people are using Mesa 12AT7 and seem satisfied as well it seems?

Thanks again!

I went with the Jan Philips in v4. Sounds great - significant improvement.
 
Thaymz said:
Hi

Agree to APEMAN’s point - the Mark V c+ mode was modelled off the non-GEQ c+ which had a smaller cap at the end of the circuit. This acts as a high pass filter so it naturally does not have a lot of bass. The GEQ can be used more aggressively to compensate. The IV mode has the larger cap if I recall which adds bass response plus as APEMAN mentioned also has PULL DEEP and BRIGHT active. So I’m a little surprised you don’t hear bass in the IV mode. There’s usually a noticeable difference between c+ and IV in both sound and feel. I do think the pull functions for pull deep and bright (all of them actually) have been made far less dramatic in the V and JP compared to the original c+. Since the Mark IV actually.

The extreme adds the thump because of the changes in the power amp similar to the Mark IV push presence. I was under the impression the IV mode is a IV circuit with presence pulled and Extreme is IV circuit with presence knob pushed. To me when I A/B them they sound almost identical but for inherent differences in level of saturation for the newer amps.

I run the bass fader on the GEQ for c+ and IV fairly high. For thump I use crunch mode with unconventional settings settings (Max Gain and Treble, Bass around 10:30-11) and it has a tonne of body. I’ve recently started using Extreme with bass around 11 which gets a rectifier style sound as well.

The JP has around as much bass as the IV mode (maybe a tad more) presuming there are no issues with your V but it sounds thicker than the c+ mode. I expect this is due to pull deep, huge transformer and different power amp.

Had you played a mark amp before?

What settings do you use (controls & GEQ)?

Thanks for the insight! I had never played a Mark V before I ordered mine (no one near had carried or had them in stock), but had noodled on a few used IVs and other Mesas in music stores previously.

IV does have noticeable more bass response than IIC+, just still no where NEAR Extreme. I did notice that Crunch on Ch. 2 has more bass response/thump than IIC+/IV, and I have been using that, actually with very similar settings to what you're using.

I've tried all sorts of settings, but here's what I've found to work best thus far:

IIC+:

Gain 2:00
Master 11:00
Pres 11:30
Treb 12:30
Mid 10:00
Bass 10:30

I've also run it with the gain almost dimed and treble & bass rolled back.


IV:

Gain 2:30-3:00
Master 10:30
Pres 12:00
Treb 1:00
Mid 9-10:00
Bass 10:00


EXTREME:

Gain 3:00-3:30
Master 10:30-11:00
Pres 1:00
Treb 11:30
Mid 9:00
Bass 9:30

Graphic EQ is always in some version of a V, generally with slider slightly higher on the bass frequencies than treble:

80 Hz just under top line
240 Hz halfway between middle and top lines
750 Hz slightly above bottom line
2200 Hz slightly above middle line
6600 Hz a bit under the top line, slightly lower than the 80 Hz slider

Usually 90w, bright switch on, pentode, full power. Though triode is nice too with IIC+, makes it a little more liquid.

Thaymz said:
I went with the Jan Philips in v4. Sounds great - significant improvement.

Great thanks! Excited to try it. Did you order yours from tubedepot?
 
Thaymz said:
Hi

Agree to APEMAN’s point - the Mark V c+ mode was modelled off the non-GEQ c+ which had a smaller cap at the end of the circuit. This acts as a high pass filter so it naturally does not have a lot of bass. The GEQ can be used more aggressively to compensate. The IV mode has the larger cap if I recall which adds bass response plus as APEMAN mentioned also has PULL DEEP and BRIGHT active. So I’m a little surprised you don’t hear bass in the IV mode. There’s usually a noticeable difference between c+ and IV in both sound and feel. I do think the pull functions for pull deep and bright (all of them actually) have been made far less dramatic in the V and JP compared to the original c+. Since the Mark IV actually.

The extreme adds the thump because of the changes in the power amp similar to the Mark IV push presence. I was under the impression the IV mode is a IV circuit with presence pulled and Extreme is IV circuit with presence knob pushed. To me when I A/B them they sound almost identical but for inherent differences in level of saturation for the newer amps.

I run the bass fader on the GEQ for c+ and IV fairly high. For thump I use crunch mode with unconventional settings settings (Max Gain and Treble, Bass around 10:30-11) and it has a tonne of body. I’ve recently started using Extreme with bass around 11 which gets a rectifier style sound as well.

The JP has around as much bass as the IV mode (maybe a tad more) presuming there are no issues with your V but it sounds thicker than the c+ mode. I expect this is due to pull deep, huge transformer and different power amp.

Had you played a mark amp before?

What settings do you use (controls & GEQ)?

I did notice that Ch.2 Crunch mode packs more thump & full frequency punch than the Ch.3 IIC+/IV, and I've been running settings very similar to yours on Crunch mode, and it's indeed a very nice Rhythm sound!

There is indeed more bass on IV than IIC+, perhaps I should have specified that better. IIC+ is the mode truly lacking the bass response for me, as very well explained by you comparing the small cap to a hi-pass filter - which I had read about before purchasing the amp, just didn't think it was THAT much! I still find IV is lacking bass response as well, but yes it audibly does have more bass than IIC+.....it's just nowhere NEAR Extreme mode, whose frequency fullness crushes.

I unfortunately did not have the opportunity to play a Mark V (or a JP2C, the other amp in consideration) before purchasing, so my decision came from extensive online research. I have played/noodled on used Mark IVs and other Mesa's.

The settings vary depending on the Ch.3 mode, but generally they're around:

Gain 1:30-3:30, sometimes dimed on IIC+
Master 10:00-11:30
Pres 11:00-1:30
Treb 11:00-1:30, treble and presence are usually offset from one another
Mid 8:45-10:30
Bass 8:30-11:00, backed off when gain is higher

GEQ is in a V, a little more bass than treble. 80 Hz fader is just about maxed for IIC+, just below the top line for IV and brought down a notch for Extreme. All faders are above the center line except the 750 Hz fader, which is just above the bottom line.

Full power, 90w, pentode, and I toggle the bright switch (and treb/pres accordingly) often trying to decide whether I prefer normal or bright, and usually bright wins, especially when I'm not standing directly inline with one of the speakers. I do use triode with IIC+ sometimes, makes it a bit more liquid for sure.

Thaymz said:
I went with the Jan Philips in v4. Sounds great - significant improvement.

Awesome, thanks! Did you order yours from TubeDepot?
 
APEMAN said:
I would go with a Jan Philips 12AT7 as well - I know there are at least 2 slightly different revisions of that tube out there, I own both, and both did the trick for me.

On my amp all 3 modes in CH3 are equally big in terms of level and bass and CH2's crunch sounds small compared to it. This comes with the higher presence you are able to dial in when the harsh frequencies are removed (I set it to about 3:30). In order to balance the sound, we tend to compensate the dominant highs with bass which is not possible. Try to go more into a increased presence (=opened poweramp) and cut 6.6kHz slider configuration.

I once thought the simulclass poweramp is the problem of that amp but thats not true - in fact I like it much better then the 45W non simul configuration. The problem of that amp are the too hot gain levels in between the preamp stages - those produce the harsh and unmusical distortion.

Ordered the Jan Philips 12AT7, very excited (and hopeful) to try it. Thanks again!
 
Apeman, I love your tone! It was your initial thread on the AT7 "mod" that made me buy my V.
Can you tell the details of the hard mods you've done?
 
I add this video on this thread, maybe it could be helpful. Anyways, is quite interesting.

https://www.youtube.com/watch?v=VO-1jVVCLMQ
 
Just wanted to provide a quick update for anyone interested. I ordered a couple AT7s and tried them following configurations:

V6 only
V4 only
V7 only
V4 and V6
V4 and V7
V6 and V7

I knew this would be complex to try and I wanted to simplify it as much as possible, so I came up with and executed the following plan: I did these all in quick succession, playing each one on Ch. 3 IIC+ mode only (most bass lacking mode) for about 1-2 minutes per configuration and then swapping to the next. I did this twice through. The first time through I left the settings exactly as they were with all AX7s, and the second time through I spent a little more time on each configuration tweaking the knobs to ear. From that rapid fire testing I decided on V4 and V7 and have left it that way for the past several weeks.

The testing went similarly to what I've read from the reports on here. I found V6 didn't have much noticeable affect, at least during that quick test. V4 had a more noticeable affect on the gain structure and allowed me to open up the presence more. V7 potentially had the most noticeable affect however, making the sound more "3D" as another user had put it. It sounded noticeably wider.

Gains on Ch. 2 & 3 now do have to be higher - pretty much dimed out now, which is pretty expected with the AT7s.

I think IIC+ and IV modes have benefitted. I've actually been able to find settings that I can use between those two modes without really having to tweak much when I'm just practicing which has been convenient. I'm still not sure if it's benefitted or hurt Extreme mode yet, though I admittedly haven't spent much time at all on it yet and I need to find better settings for it I think.

Ch. 2 Crunch mode though I fear has suffered; it sounded pretty great with all AX7s. Even with the gain dimed, it definitely doesn't pack quite the same punch and it now has a sound in a very different realm than Ch. 3, where as previously I found I could get them at least somewhat similar. I have not tried any type of pedal to hit the front of the amp yet though, so that could potentially help it.

As far as the root of this post, the bass response: I do think it's a little bit better with the AT7s and the setting adjustments I've been able to make, but not a world of difference by any means.

After having spent some solid time playing V4 & v7, I'm getting ready to try to test again with the above configurations. I'll do my best to report back with any more info! Thanks again to all.
 

Latest posts

Back
Top