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Tube amps to control VR-4jr bass?

Hi,

I recently bought a pair of VR-4jr (I think it's MK 1) from a local shop in Indonesia. They should be delivered to my house within couple days.

Does anyone know what amps were used during the design stage to voice this speakers?

Currently my power amp is Conrad Johnson MV-55 50W EL34. I do not know if this amp would work well with VR-4jr since I could not do a home audition. I bought the speakers because the soundstaging and image focus was excellent and the speakers overall sound very dynamic although I had problems with bass during audition.

During audition at the dealer yesterday, I paired the speakers with the following amps; all configured with Cary SLP-98 preamp, speaker cable is single wiring and source was Cary 303 CD. No lead shot and spikes were used :

- Cary V12 EL34 set to 100W ultralinear. The bass is very thin and not enough amplitude.
- Rogue Audio Stereo amp 90W KT88. Bass was very boomy.
- Genesis Integrated with KT88 60w. Bass was not boomy but not enough punch
- Cary Cinema 2 200W stereo

I also tried bi-amping Cary V12 for the upper part and Cary Cinema 2 for the bass. The bass was still boomy but not as bad as with the Rogue Audio and I prefer not doing bi-amping to keep things simpler. I also heard other speakers to compare in the same room with similar setup. Vienna Acoustics Mahler: Bass was big but maybe too much. Vienna Acoustics Baby Beethoven Grand: Bass was good but soundstage sound small. Room size was 4.5m x 5.5m x 2.7m (15 x 18 x 9 ft).

Can you suggest several potentially good amp to match the speakers? My concern would be with controlling boomy bass I heard during audition. I don't hear very loud music. Mostly female vocals, jazz and classical orchestra. No deafening heavy music. Would a 90-100W tube be enough since I have problems with both the Cary and Rogue audio, both of which have power rating around 100w? I prefer tubes, but am open to SS amps if necessary.

I am interested in VTL MB125 monoblock with 4 EL34 130W ultra linear at 4 Ohm ot 100W at 8 Ohm or VTL ST150. My other alternative would be VTL MB185 monoblock with 6 6550 230W ultra linear at 4 Ohm or 165W at 8 Ohm. I cannot do a home audition since most dealears are located 600 miles from where I live.

Thanks in advance.

Best Regards,

Hogio Setiawan
hogio
5 responses Add your response
richmon
243 posts
 
No input on the amp, just thought I'd prepare you for the sticker shock of lead shot. I just purchased a 25# bag at Bass pro shop for $36. !!

Seems with two wars raging, the price of lead has 'shot up'.

Suggest putting a trash compacter bag in the speaker before filling, if you ever want to remove it for moving purposes, you'll be glad you did.
I moved my JR's with the shot in them (I'm 6'2", 200 lbs) along with another similarly sized helper and we both almost got measured for hernia trusses afterward.
hogio OP
1 posts
 
Thanks for the suggestions.

The speakers arrived a few days ago. I set them biwire. The bass is very good, not boomy at all; and this is with CJ MV-55. I thought these speakers needed lots of watts.

However, I notice that the bass tuning ports have gray foams. The foam is about 2/3" thick and were rolled so that they formed as tubes covering the length of the bass ports. I tried to remove it at first, but then hesitated since they seemed glued to the port. Are they supposed to stay on? What were their purpose? If I removed it, what would happen to the sound?

Thanks.
bartinmi
30 posts
 
I agree with Zaikesman. I do own a pair of VS VR4jr's and I would also be sure to add lead shot and spikes to the speakers before making any other changes to control boomy bass. If possible set these speakers out into the room further or even fill the front port with foam to improve the bass tightness.
zaikesman
3,017 posts
 
Hogio: I have no experience with the speakers you bought, and don't know anything about how difficult they are in the bass with tubes. However, I have owned both the CJ MV55 and VTL MB-185 amps. As you would expect, the more powerful monoblock VTLs reveal more detail and have more bass control. But if your room isn't large, the little MV55 can be a very nice sounding amp. To me the first thing you should do is live with the combination you have for a while, both until the speakers are broken in and until you have experimented with speaker positioning and gotten acclimated to their sound in your room with your current amp. I'd say give at least 1-2 months before making any new moves about amps. Also, if your MV55 is fitted with the stock Sovtek tubes and/or they could use replacement now, I would recommend using SED EL34 output tubes, Shuguang 6SN7 driver tubes, and EI 12AX7 input tubes (matched and selected for low noise/microphonics), unless you use NOS. In any case, don't expect what you heard of the bass at your dealer's to necessarily translate directly to what you'll hear in your own room -- bass response is too influenced by the room and speaker setup (and even speaker cables) to under different circumstances simply assign various characteristics to partnering amps or tube types in isolation. Enjoy your new speakers!
fishwater
178 posts
 
VSA uses Spectron amps to voice the speakers, they used to use Bel Canto but switched over to Spectron eventually. It is not uncommon to see the speakers used with tubes at a show, I ran mine with a BAT VK60 for over a year & was very pleased with the sound. I would suggest a tube amp with a minimum of 60wpc, they can handle more & will respond well with bi-amping tubes & solid state.
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